Recovery Plan

for the

Cook Inlet Beluga Whale

(Delphinapterus leucas)

National Marine Fisheries Service

National Oceanic and Atmospheric Administration

December 2016
Cover photo is a composite of two photographs and was created specifically for this document.

Use by permission only:

Anchorage photo: Michael Benson 

Beluga photo: T. McGuire, LGL Alaska Research Associates, Inc., under MMPA/ESA

Research permit # 14210

Cook Inlet Beluga Whale DISCLAIMER

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DISCLAIMER

Recovery plans delineate such reasonable actions as may be necessary, based upon the best 

scientific and commercial data available, for the conservation and survival of listed species.

Plans are published by the National Marine Fisheries Service (NMFS), sometimes prepared with 

the assistance of recovery teams, contractors, State agencies, and others. Recovery plans do not 

necessarily represent the views, official positions, or approval of any individuals or agencies 

involved in the plan formulation, other than NMFS. They represent the official position of 

NMFS only after they have been signed by the Assistant Administrator. Recovery plans are 

guidance and planning documents only; identification of an action to be implemented by any 

public or private party does not create a legal obligation beyond existing legal requirements.

Nothing in this plan should be construed as a commitment or requirement that any Federal 

agency obligate or pay funds in any one fiscal year in excess of appropriations made by Congress 

for that fiscal year in contravention of the Anti-Deficiency Act, 31 U.S.C. § 1341, or any other 

law or regulation. Approved recovery plans are subject to modification as dictated by new 

findings, changes in species status, and the completion of recovery actions.

LITERATURE CITATION SHOULD READ AS FOLLOWS:

National Marine Fisheries Service. 2016. Recovery Plan for the Cook Inlet Beluga Whale

(Delphinapterus leucas). National Marine Fisheries Service, Alaska Region, Protected 

Resources Division, Juneau, AK.

Hard copies of this recovery plan may be obtained from:

National Marine Fisheries Service

Alaska Region

P.O. Box 21668

Juneau, AK 99802-1668

907-586-7235

Digital copies of this recovery plan may be downloaded from the NMFS Alaska Region website:

http://alaskafisheries.noaa.gov/

All NMFS recovery plans can be downloaded from the NMFS website:

http://www.nmfs.noaa.gov/pr/recovery/plans.htm
Cook Inlet Beluga Whale ACKNOWLEDGEMENTS

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ACKNOWLEDGEMENTS

The National Marine Fisheries Service (NMFS) gratefully acknowledges the Cook Inlet 

Beluga Whale Recovery Team (CIBRT), led by Dr. Tamara McGuire, for their work in 

developing the first draft of this Recovery Plan for the Cook Inlet Beluga Whale. The members 

of the CIBRT are listed below. Science Panel members were selected for their expertise and 

Stakeholder Panel members represented their respective organizations. The identification of 

recovery team members below does not imply their endorsement of this final version of the 

recovery plan.

CIBRT Science Panel: Dr. Pierre Béland (St. Lawrence National Institute of 

Ecotoxicology); Dr. William Bechtol (Bechtol Research); Dr. Manuel Castellote (NMFS Alaska 

Fisheries Science Center, Marine Mammal Laboratory); Dr. Carrie Goertz (Alaska SeaLife 

Center); Dr. Daniel Goodman (Montana State University); Dr. Rod Hobbs (NMFS Alaska 

Fisheries Science Center, Marine Mammal Laboratory); Craig Matkin (North Gulf Oceanic 

Society); Dr. Tamara McGuire (LGL Alaska Research Associates); Dr. Robert Michaud (Group 

for Research and Education of Marine Mammals); Dr. Greg O’Corry-Crowe (Harbor Branch 

Oceanographic Institute); Randy Standifer, Sr. (preceded by the late Peter Merryman) (Cook 

Inlet Marine Mammal Council); Dr. Robert Suydam (North Slope Borough).

CIBRT Stakeholder Panel: Bruce Anders (Cook Inlet Region, Inc.); Joel Blatchford 

(Alaska Native Marine Mammal Hunters Committee); Jason Brune (Resource Development 

Council of Alaska, Inc.); Mayor David Carey (Kenai Peninsula Borough); Karla Dutton 

(Defenders of Wildlife); Chris Garner (Joint Base Elmendorf Richardson); Willie Goodwin 

(Alaska Beluga Whale Committee); Page Herring (Northern District Set Netters Association of 

Cook Inlet); Brett Jokela (Anchorage Water and Wastewater Utility); Nancy Lord (Cook 

Inletkeeper); Nikki Martin (Alaska Oil and Gas Association); Roland Maw (United Cook Inlet 

Drift Association); Andrew Niemiec (Knik Arm Bridge and Toll Authority); Eileen Probasco 

(Matanuska-Susitna Borough); Steve Ribuffo (Port of Anchorage); John Schoen (National 

Audubon Society); Paul Shadura (Kenai Peninsula Fishermen’s Association); George Vakalis 

(Anchorage Municipality); Doug Vincent-Lang (Alaska Department of Fish and Game).

NMFS also thanks the following individuals for their time and contributions to the recovery 

planning process, but who for various reasons were only able to participate on the CIBRT for a 

short duration: Dr. Robert Small (Alaska Department of Fish and Game), Dr. Mark Willette

(Alaska Department of Fish and Game), Christine Nelson (Matanuska-Susitna Borough), and 

Kate Williams (Alaska Oil and Gas Association).
Cook Inlet Beluga Whale ACKNOWLEDGEMENTS

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The Cook Inlet Beluga Whale Recovery Team acknowledges the following for their 

contributions and support toward the development of the Recovery Plan for the Cook Inlet 

Beluga Whale: 

Individuals: Marc Bourdon, Kathy Burek-Huntington, Joe Canesi, Dale Funk, Ken 

Goldman, Richard Gustafson, Glenn Hollowell, Sam Ivey, Jon Kurland, Michael Link, Barb 

Mahoney, Barry McPherson, Scott Meyer, Mandy Migura, Lucy Moore, Mark Nelson, Steve 

Okkonen, Ted Otis, Lori Quakenbush, Scott Raborn, Tim Ragen, Randall Reeves, Susan Saupe, 

Kate Savage, Kim Shelden, Patrick Shields, Bob Small, Brad Smith, Mark Willette, Sheyna 

Wisdom

Supporting Organizations: Alaska SeaLife Center; Bechtol Research; Georgia Aquarium; 

the Group for Research and Education on Marine Mammals (GREMM); LGL Alaska Research 

Associates, Inc.; the Marine Mammal Commission; the Alaska Fisheries Science Center. Marine 

Mammal Laboratory (AFSC MML); North Gulf Oceanic Society; St. Lawrence National 

Institute of Ecotoxicology; United States Air Force; United States Army

The Cook Inlet Beluga Whale Recovery Team dedicated their work to the memories of their

esteemed and appropriately named colleagues, Mr. Peter Sunrise Merryman and Dr. Daniel 

Goodman. The belugas, the Recovery Team, and the Plan have all benefited from their care and 

efforts. 
Cook Inlet Beluga Whale TABLE OF CONTENTS

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TABLE OF CONTENTS

DISCLAIMER................................................................................................................................ i

ACKNOWLEDGEMENTS ......................................................................................................... ii

EXECUTIVE SUMMARY ........................................................................................................ xii

I. INTRODUCTION.......................................................................................................... I-1

A. The Importance of Belugas to Cook Inlet...................................................................I-1

B. History of the Listing Status of Belugas in Cook Inlet...............................................I-1

C. Designation of Critical Habitat for CI Belugas...........................................................I-4

D. Recovery and Recovery Plans ....................................................................................I-5

E. The Recovery Plan for CI Belugas .............................................................................I-5

F. Section Summary: Introduction ..................................................................................I-7

II. BACKGROUND ...........................................................................................................II-1

A. Physical Habitat of Cook Inlet...................................................................................II-1

B. Natural History of CI Belugas ...................................................................................II-5

1. Physical Description of Belugas.........................................................................II-5

2. Taxonomy, Geographic and Genetic Variation..................................................II-5

3. Beluga Distribution in Cook Inlet ......................................................................II-6

a. Distribution Patterns: 1970s, 1990s, and 2000s................................................. II-7

b. Seasonal Distribution Patterns........................................................................... II-8

4. CI Beluga Habitat Characteristics and Use ......................................................II-13

a. CI Beluga Feeding Habitat .............................................................................. II-13

b. CI Beluga Calving Habitat............................................................................... II-18

c. Other Uses of Habitat ...................................................................................... II-18

d. Human Environment of Cook Inlet ................................................................. II-19

5. Age, Growth, Reproduction, and Survival.......................................................II-19

6. Hearing and Vocalizations ...............................................................................II-25

a. Beluga Hearing ................................................................................................ II-25

b. Beluga Echolocation........................................................................................ II-25

c. Beluga Acoustic Social Signals....................................................................... II-26

d. Acoustics of CI Belugas .................................................................................. II-27

7. Other Senses.....................................................................................................II-28

8. Social Organization ..........................................................................................II-29

9. Swimming and Diving Behavior......................................................................II-29

10. Foraging Behavior, Diet, and Fisheries Management......................................II-30

a. Foraging Behavior ........................................................................................... II-30

b. Diet .................................................................................................................. II-31

c. Fisheries Management ..................................................................................... II-33

C. CI Beluga Population Size and Trends....................................................................II-34

1. Historic Abundance Estimate and Carrying Capacity......................................II-34

2. Recent Abundance Estimates and Population Trends......................................II-34

3. Small Population Dynamics.............................................................................II-35

4. CI Beluga Population Viability Analysis (PVA) .............................................II-38

D. Sources of CI Beluga Mortality or Injury................................................................II-39

1. Natural Sources ................................................................................................II-39

a. Predation.......................................................................................................... II-39

b. Strandings........................................................................................................ II-43

2. Anthropogenic Sources ....................................................................................II-46
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a. Subsistence Harvest......................................................................................... II-46

b. Commercial Whaling....................................................................................... II-48

c. Poaching or Intentional Harassment................................................................ II-48

d. Incidental Mortalities or Injuries ..................................................................... II-48

3. Cause of Death Analysis of Necropsied CI Belugas........................................II-50

E. Section Summary: Background ...............................................................................II-51

III. THREATS TO RECOVERY..................................................................................... III-1

A. Discussion of Threat Types ..................................................................................... III-5

1. Threat Type: Catastrophic Events.................................................................... III-5

a. Potential Sources of a Catastrophic Event........................................................III-5

b. Relative Concern...............................................................................................III-6

2. Threat Type: Cumulative Effects of Multiple Stressors................................... III-7

a. Potential Cumulative Effects of Multiple Stressors..........................................III-7

b. Relative Concern.............................................................................................III-10

3. Threat Type: Noise......................................................................................... III-10

a. Sources of Noise in Cook Inlet.......................................................................III-10

b. Potential Effects of Noise on CI Belugas .......................................................III-12

c. Relative Concern.............................................................................................III-13

4. Threat Type: Disease Agents ......................................................................... III-13

a. Sources and Types of Disease Agents in Cook Inlet ......................................III-13

b. Relative Concern.............................................................................................III-13

5. Threat Type: Habitat Loss or Degradation..................................................... III-14

a. Sources of Habitat Loss or Degradation in Cook Inlet...................................III-14

b. Relative Concern.............................................................................................III-15

6. Threat Type: Reduction in Prey ..................................................................... III-15

a. Competition for Prey Resources.....................................................................III-16

b. Disturbance or Modification of Prey Habitat..................................................III-16

c. Anthropogenic Noise Effects on CI Beluga Prey ...........................................III-18

d. Relative Concern.............................................................................................III-18

7. Threat Type: Unauthorized Take ................................................................... III-19

a. Sources of Unauthorized Take........................................................................III-20

b. Relative Concern.............................................................................................III-21

8. Threat Type: Pollution.................................................................................... III-22

a. Sources and Types of Pollution in Cook Inlet ................................................III-22

b. Relative Concern.............................................................................................III-23

9. Threat Type: Predation................................................................................... III-24

a. Predation by Killer Whales.............................................................................III-25

b. Predation by Sharks........................................................................................III-25

c. Predation Effects on a Small Population (i.e., predator pit) ...........................III-26

d. Relative Concern.............................................................................................III-26

10. Threat Type: Subsistence Hunting ................................................................. III-26

a. Legal Subsistence Hunting .............................................................................III-26

b. Relative Concern.............................................................................................III-27

B. State of Alaska’s List of Threats to CI Belugas..................................................... III-28

C. Section Summary: Threats to Recovery ................................................................ III-29

IV. RECOVERY STRATEGY..........................................................................................IV-1

V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA........................................ V-1

A. Recovery Goals......................................................................................................... V-1

B. Recovery Objectives................................................................................................. V-1
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C. Recovery Criteria ...................................................................................................... V-1

1. Downlisting Criteria for Reclassifying CI Belugas from “Endangered” to 

“Threatened” ..................................................................................................... V-2

a. Downlisting Demographic Criterion..................................................................V-2

b. Downlisting Threats-Based Criteria ..................................................................V-3

2. Delisting Criteria for Considering CI Belugas “Recovered” ............................ V-4

a. Delisting Demographic Criteria.........................................................................V-4

b. Delisting Threats-Based Criteria........................................................................V-5

VI. RECOMMENDED RECOVERY ACTIONS ...........................................................VI-1

A. Recovery Actions and Narrative..............................................................................VI-2

VII. IMPLEMENTATION SCHEDULE ........................................................................VII-1

VIII. LITERATURE CITED ........................................................................................... VIII-1

IX. APPENDICES..............................................................................................................IX-1

A. Federal Actions and Regulations for CI Belugas.....................................................IX-3

B. Existing Conservation Efforts..................................................................................IX-5

C. Recovery Planning for CI Belugas ........................................................................IX-19

D. CI Beluga Natural History Supplement .................................................................IX-23

E. CI Beluga Hearing, Vocalization, and Noise Supplement.....................................IX-25

F. CI Beluga Prey Supplement...................................................................................IX-33

G. CI Beluga Pollution and Contaminants Supplement .............................................IX-53

H. Summary of a Cause of Death Analysis of 34 Necropsied CI Belugas.................IX-63

I. Common and Scientific Names of Species............................................................IX-71
Cook Inlet Beluga Whale LIST OF FIGURES

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LIST OF FIGURES 

Figure 1. CI beluga critical habitat (76 FR 20180, April 11, 2011). ............................................I-6

Figure 2. Major streams and rivers flowing into Cook Inlet....................................................... II-2

Figure 3. Glacial input into Cook Inlet. ...................................................................................... II-3

Figure 4. Cook Inlet bathymetry and locations of major tide rips.............................................. II-4

Figure 5. Map of summer distributions of the beluga stocks in Alaska. .................................... II-6

Figure 6. Areas occupied by belugas in Cook Inlet, Alaska, in June/July 1978 to 1979............ II-9

Figure 7. Areas occupied by belugas in Cook Inlet, Alaska, in June/July 1993 to 1997.......... II-10

Figure 8. Areas occupied by belugas in Cook Inlet, Alaska, in June 1998 to 2008. ................ II-11

Figure 9. Areas occupied by belugas in Cook Inlet, Alaska, in June 2009 to 2014. ................ II-12

Figure 10 (a–h). Predicted CI beluga distribution by month based on known locations of 14 

satellite-tagged belugas. ..................................................................................... II-14

Figure 11. General geographic distribution of current and proposed human activities in 

Cook Inlet, Alaska.............................................................................................. II-20

Figure 12. Audiograms from wild belugas and captive belugas............................................... II-25

Figure 13. Estimated abundance of CI belugas, 1994–2014, with 95% confidence intervals 

for each estimate (vertical bars). ........................................................................ II-36

Figure 14. Summary of reported CI beluga subsistence harvests and estimated numbers 

struck and lost, 1987 to 2016. ............................................................................ II-47
Cook Inlet Beluga Whale LIST OF TABLES

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LIST OF TABLES

Table 1. Review of female beluga life history parameters found in the published literature. .. II-22

Table 2. Prey items from CI beluga stomachs, 2002 to 2010................................................... II-32

Table 3. CI beluga abundance estimates and coefficients of variance (CVs), June/July 1994 

to 2014................................................................................................................ II-35

Table 4. Reported killer whale observations in upper Cook Inlet, and reports of killer whale 

predation on CI belugas Inlet-wide, 1982–2016................................................ II-40

Table 5. CI beluga stranding records (for beach-cast or floating carcasses, and live 

strandings), 1988–2016...................................................................................... II-44

Table 6. Summary of threats assessment for CI belugas. ..........................................................III-3

Table 7. Events releasing more than 10,000 pounds or gallons of reportable substances into 

Cook Inlet, 1994–2011........................................................................................III-7

Table 8. Compounds of probable and possible concern for CI belugas, for which data are 

available either for CI belugas or for other beluga populations........................III-24

Table 9. Criteria for considering reclassification (from endangered to threatened, or from 

threatened to not listed) for CI belugas................................................................ V-7
Cook Inlet Beluga Whale LIST OF ACRONYMS AND ABBREVIATIONS

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LIST OF ACRONYMS AND ABBREVIATIONS

ACMP Alaska Coastal Management Program

ADEC Alaska Department of Environmental Conservation

ADF&G Alaska Department of Fish and Game

AFSC MML Alaska Fisheries Science Center, Marine Mammal Laboratory (formerly National 

Marine Mammal Laboratory [NMML])

AKR Alaska Region

ASM age at sexual maturity

°C degrees Celsius

CFR Code of Federal Regulations

CI beluga Cook Inlet beluga whale

CIBRT Cook Inlet Beluga Whale Recovery Team 

CIMMC Cook Inlet Marine Mammal Council

CIRI Cook Inlet Region, Inc. 

CITES Convention on International Trade in Endangered Species of Wild Fauna and 

Flora

cm centimeter

Corps United States Army Corps of Engineers

CV coefficient of variation

CWA Clean Water Act

CZMA Coastal Zone Management Act

dB decibel

DPS distinct population segment

DDT dichlorodiphenyltrichloroethane, a chlorinated pesticide

DFO Department of Fisheries and Oceans

EPA Environmental Protection Agency

ESA Endangered Species Act

°F degrees Fahrenheit

FR Federal Register

ft feet

FWCA Fish and Wildlife Coordination Act

GLG growth layer group

HABs harmful algal blooms

HCB hexachlorobenzene

HCH hexachlorocyclohexane

Hz hertz

IHA incidental harassment authorization

IUCN International Union for the Conservation of Nature and Natural Resources

KABATA Knik Arm Bridge and Toll Authority
Cook Inlet Beluga Whale LIST OF ACRONYMS AND ABBREVIATIONS

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kg kilogram

kHz kilohertz

km kilometer

km2 square kilometer

km/hr kilometer per hour

lb pound

LGL LGL Alaska Research Associates, Inc.

m meter

mg milligram

MHW mean high water

MMC Marine Mammal Commission

MMO marine mammal observer

MMPA Marine Mammal Protection Act

mi mile

mi2 square mile

mi/hr miles per hour

mtDNA mitochondrial DNA

NGO non-governmental organization

NMFS National Marine Fisheries Service

NOAA National Oceanic and Atmospheric Administration

NPDES National Pollutant Discharge Elimination System

OSP optimum sustainable population

PAH polycyclic aromatic hydrocarbon

PFC perfluorinated compound

PBDE polybrominated diphenyl ether

PCB polychlorinated biphenyls

ppt parts per thousand

PTS permanent threshold shift

PVA population viability analysis

SD standard deviation

SE standard error

SEDAR SouthEast Data, Assessment, and Review

SLE St. Lawrence Estuary

TEK Traditional Ecological Knowledge

TTS temporary threshold shift

URS URS Corporation

μPa microPascal

USFWS United States Fish and Wildlife Service
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Cook Inlet Beluga Whale EXECUTIVE SUMMARY

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EXECUTIVE SUMMARY

Current Status

The best available historical abundance estimate of 1,293 Cook Inlet beluga whales (CI 

belugas, Delphinapterus leucas) was obtained from an aerial survey conducted in 1979 (Calkins 

1989). The National Marine Fisheries Service (NMFS) has adopted 1,300 as the value for the 

carrying capacity to be used for management purposes.

NMFS began conducting comprehensive and systematic aerial surveys of CI belugas in 1993. 

These surveys documented a decline in CI beluga abundance from 653 whales in 1994 to 347 

whales in 1998, a decline of nearly 50%. This rapid decline was associated with a substantial, 

unregulated subsistence hunt.

In 1999, in response to this dramatic decline NMFS received one petition to designate CI 

belugas as depleted under the Marine Mammal Protection Act (MMPA) and two petitions to list 

them as endangered under the Endangered Species Act (ESA). In 2000, NMFS designated the CI 

beluga stock as depleted under the MMPA, but determined that listing CI belugas as threatened 

or endangered under the ESA was not warranted at that time.

Subsequent cooperative efforts between NMFS and Alaska Native subsistence users 

dramatically reduced subsistence hunts beginning in 1999. This reduction in hunting should have 

allowed the CI beluga population to begin increasing at an expected growth rate of between 2% 

and 6% per year if subsistence harvest was the only factor limiting population growth; however, 

abundance data collected since 1999 indicated that the population did not increase as expected.

This lack of population growth led NMFS to reevaluate the status of CI belugas. In October 

2008, NMFS finalized the Conservation Plan for the Cook Inlet Beluga Whale (Conservation 

Plan; NMFS 2008a), as required by the MMPA for any species or stock designated as depleted. 

The Conservation Plan reviewed and assessed the known and possible threats influencing CI 

belugas. During that same month NMFS listed the CI beluga whale distinct population segment 

(DPS1

) as endangered under the ESA (73 FR 62919, October 22, 2008).

The most recent comprehensive survey for CI belugas from 2014 indicates a point estimate 

of 340 belugas, with the population continuing to show a negative trend since 1999 (a decline of 

1.3% per year; Shelden et al. 2015a).

Threats to Recovery

CI belugas are the most reproductively and demographically isolated of all the Alaskan 

belugas, and are unique in Alaska given that their habitat, a semi-enclosed tidal estuary in 

southcentral Alaska, is in close proximity to the greatest concentration of Alaska’s human 

population. Belugas are predominately found in nearshore waters. The distribution of CI belugas 

 

1 DPS is a vertebrate population or group of populations that is discrete from other populations and significant in relation to the 

entire taxon (61 FR 4722; February 7, 1996). The ESA defines “species” to include any subspecies and any DPS of vertebrate 

fish or wildlife that interbreeds when mature (16 U.S.C. § 1532(16)). Throughout this recovery plan, the terms “CI beluga 

population,” “CI beluga whales,” and “CI belugas” refer to the CI beluga whale DPS (CI belugas).
Cook Inlet Beluga Whale EXECUTIVE SUMMARY

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has changed significantly since the 1970s, and the summer range has contracted to the upper 

Inlet in recent years, coincident with the decline in population size.

Ten potential threat types are identified and assessed in this recovery plan, based on current 

knowledge of threat factors. Assessments were made based on the information and data gaps 

presented in the plan’s Background section. Climate change, while considered a potential threat 

to CI beluga recovery, is not addressed as a separate threat, but rather is discussed with respect to 

how it may affect each of the listed threats. The ten identified potential threats and their overall 

relative concern to the CI beluga population discussed in this plan include:

• Threats of High Relative Concern

o Catastrophic events (e.g., natural disasters; spills; mass strandings);

o Cumulative effects of multiple stressors; and

o Noise.

• Threats of Medium Relative Concern

o Disease agents (e.g., pathogens, parasites, and harmful algal blooms);

o Habitat loss or degradation;

o Reduction in prey; and

o Unauthorized take.

• Threats of Low Relative Concern

o Pollution;

o Predation; and

o Subsistence hunting.

Recovery Plan

The ESA requires the preparation and implementation of recovery plans for all listed species, 

unless the Secretary of Commerce determines that doing so does not promote the recovery of the 

species. In 2010, NMFS began the process of developing a recovery plan for CI belugas by 

announcing its intent to prepare a recovery plan and soliciting public comments (75 FR 4528, 

January 28, 2010). In February 2010, NMFS prepared a recovery outline, which, in concert with 

the Conservation Plan, served as an interim guidance document to direct recovery efforts until a 

full recovery plan was finalized. In March 2010 NMFS convened a Recovery Team to aid in the 

development of a draft recovery plan for CI belugas. The Recovery Team was composed of two 

advisory groups: a Science Panel and a Stakeholder Panel. In March 2013, the Recovery Team 

provided NMFS with the first draft of the recovery plan. This marked the completion of the 

team’s work; therefore it disbanded and NMFS took responsibility for finalizing the recovery 

plan. NMFS released a final draft version of the recovery plan for public comment in May 2015 

(80 FR 27925, May 15, 2015). During this public comment period, NMFS also obtained peer 

review of the draft recovery plan from five reviewers. NMFS considered all of the peer review 

and public comments and information received on the draft recovery plan in developing this final 

plan.
Cook Inlet Beluga Whale EXECUTIVE SUMMARY

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Recovery Strategy

We know the CI beluga population is not recovering as expected after the regulation of 

subsistence hunting in 1999, but we do not know why. In light of the CI belugas’ recent 

population decline, small overall population size, life history characteristics, and increasing 

number of potential threats, it is challenging to identify the most immediate needs for the 

recovery of CI belugas. Until we know which threats are limiting this species’ recovery, the 

strategy of this recovery plan is to focus recovery efforts on threats identified as of medium or 

high relative concern. This will focus efforts and resources on actions that are more likely to 

benefit CI beluga recovery. Therefore, the recovery criteria and recovery actions outlined in the 

following sections address the threats of medium (disease agents, habitat loss or degradation, 

reduction in prey, and unauthorized take) or high (catastrophic events, cumulative effects of 

multiple stressors, and noise) relative concern, and do not discuss in detail the threats of low 

relative concern. To ensure the recovery plan remains strategic, the status of threats ranked as

low relative concern will be reassessed periodically to determine whether the significance of one 

or more of these threats has elevated to the point that recovery actions need to be defined.

The recovery actions in this recovery plan include research, management, monitoring, and 

education/outreach efforts, since a comprehensive approach to CI beluga recovery is likely to 

have greater success than focusing on any one type of action. There are also actions targeted at 

incorporating new information and conducting regular reassessments, making this recovery plan 

an adaptive management plan. Threats-based recovery actions attempt to improve our 

understanding of whether a particular threat is limiting recovery. The plan also includes

recommended actions to eliminate or mitigate threats of medium or high relative concern, and to 

improve our understanding of, and ability to manage those threats. As such, the strategy of this 

recovery plan is to:

• Continue to monitor the status of the CI beluga population and improve the 

understanding of CI beluga biology;

• Improve the understanding of the effects of threats of medium or high relative concern on 

CI belugas;

• Improve the management of threats of medium or high relative concern to reduce or 

eliminate the effects of those threats on CI belugas;

• Periodically reassess whether the relative concern of each potential threat identified in 

this plan has changed over time;

• Integrate research findings into current and future management actions; and

• Keep the public informed and educated about the status of CI belugas, the threats limiting 

their recovery, and how the public can help achieve recovery of these whales.

Recovery Goals

The goal of this recovery plan is to guide efforts that achieve the recovery of CI belugas to a 

level sufficient to warrant their removal from the federal List of Endangered and Threatened 

Wildlife and Plants under the ESA (i.e., delist) by meeting the recovery criteria and addressing 

threats. The intermediate goal is to guide efforts that result in reclassification of CI belugas from 

endangered to threatened (i.e., downlist). The determinations regarding whether these goals are 
Cook Inlet Beluga Whale EXECUTIVE SUMMARY

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met include consideration of the population’s risk of extinction and threats as identified under the 

ESA section 4(a)(1) factors. If a species is determined to be recovered, then the protections 

afforded by the ESA no longer apply, although other pertinent federal (e.g., MMPA) and state 

protections will still apply.

Recovery Objectives

Five factors identified in ESA section 4(a)(1) inform NMFS’s decision as to whether a 

species merits listing as threatened or endangered under the ESA (see Section I.B. History of the 

Listing Status of CI Belugas). These factors must be considered in listing decisions as well as 

downlisting and delisting, with objectives related to each factor included as part of the recovery 

criteria. The following recovery objectives were identified for CI belugas and linked to the five 

ESA section 4(a)(1) factors:

• Ensure adequate habitat exists to support a recovered population of CI belugas. Habitat 

needs include sufficient quantity, quality, and accessibility of prey species (Factor A: the 

present or threatened destruction, modification, or curtailment of its habitat or range);

• Ensure that commercial, recreational, scientific, or educational activities are not 

inhibiting the recovery of CI belugas (Factor B: overutilization for commercial, 

recreational, scientific, or educational purposes);

• Ensure that the effects of diseases and disease agents on CI beluga reproduction and 

survival are not limiting the recovery of the CI beluga population (Factor C: disease or 

predation);

• Ensure that regulatory mechanisms other than the ESA are adequate to prevent the 

recurrence of threats to the sustainability of CI belugas (Factor D: the inadequacy of 

existing regulatory mechanisms); and

• Continue monitoring the population to identify and mitigate any new natural or manmade 

factors affecting the recovery of CI belugas (Factor E: other natural or manmade factors 

affecting its continued existence).

Recovery Criteria

Under section 4(f)(1) of the ESA, recovery plans must contain objective, measurable criteria 

which, when met, would result in a determination that the species be delisted. This recovery plan 

contains both demographic criteria (e.g., population size and trend) and threats-based criteria 

(i.e., addressing the five ESA section 4(a)(1) factors) which would indicate that downlisting or 

delisting the species should be considered.

The threats-based recovery criteria are designed to evaluate the five factors described in the 

ESA listing determination for CI belugas, with objectives related to each factor included as part 

of the recovery criteria. The downlisting and delisting criteria specified in the recovery plan are 

organized according to the five factors, then by the threat types ranked as medium or high 

relative concern.

We note that recovery under the ESA is an iterative process with periodic analyses to provide 

feedback into the species’ listing status and progress toward recovery. The ESA requires a 

review of the status of each listed species at least once every five years after it is listed. Periodic 
Cook Inlet Beluga Whale EXECUTIVE SUMMARY

Recovery Plan

xvi

review of the species may lead to updates or revisions to the recovery plan, changes in the listing 

status of the species, or delisting. While meeting all of the recovery criteria would indicate that 

the species should be delisted, it is possible that delisting could occur without meeting all of the 

recovery criteria if the best available information indicated that the species no longer met the 

definition of endangered or threatened. Changes to the species’ status and delisting would be 

made through additional rulemaking after considering the same five ESA factors considered in 

listing decisions, taking new information into account.

Summary of Recovery Criteria for CI Belugas

Status Demographic Criteria Threats-Based Criteria

Reclassified from 

Endangered to 

Threatened

(i.e., downlisted)

The abundance estimate for CI 

belugas is greater than or equal to 

520 individuals, and there is 95% or 

greater probability that the most 

recent 25-year population 

abundance trend (where 25 years 

represents one full generation) is 

positive.

AND

The 10 downlisting threats-based 

criteria are satisfied (see Section 

V.C.1.b. Downlisting Threats-Based 

Criteria).

Reclassified to 

Recovered

(i.e., delisted) 

The abundance estimate for CI

belugas is greater than or equal to 

780 individuals, and there is 95% or 

greater probability that the most 

recent 25-year population 

abundance trend (where 25 years 

represents one full generation) is 

positive.

AND

The 10 downlisting and 9 delisting 

threats-based criteria are satisfied

(see Section V.C.1.b. Downlisting 

Threats-Based Criteria; and Section 

V.C.2.b. Delisting Threats-Based 

Criteria).

Recovery Actions

This recovery plan provides a listing of recommended research, management, and 

education/outreach actions targeted at recovering CI belugas. Overall, these actions are 

organized in two categories: 1) population monitoring, recovery plan implementation, and 

education/outreach actions; and 2) threats management actions. The population monitoring,

recovery plan implementation, and education/outreach actions are designed to allow for the 

effective implementation of this recovery plan. Continued monitoring of the CI beluga 

population is essential to improve our understanding of the whales and as a means to determine if 

recovery of the CI beluga population is occurring. A multi-faceted education/outreach action is 

important to keep the public apprised of the status and outcome of the recovery actions. The 

threats management actions encompass actions aimed at assessing and managing the threats 

ranked as medium or high relative concern. Each of these threats has three subsets of actions: 1) 

actions to assess whether that threat is limiting CI beluga recovery; 2) actions that will improve 

the understanding of, and ability to manage that threat; and 3) actions that eliminate or mitigate 

that threat.

This recovery plan is a dynamic document that will change over time based on the progress 

of recovery and the availability of new information. As new information is obtained, additional 

actions may be identified and incorporated into the plan or some actions which are no longer 
Cook Inlet Beluga Whale EXECUTIVE SUMMARY

Recovery Plan

xvii

relevant may be modified or omitted. As is the case for all recovery plans under the ESA, NMFS 

will review this plan regularly and will assess the relative success of these actions in protecting 

CI belugas. Recovery actions and criteria may be changed or added accordingly.

Implementation Schedule

The Implementation Schedule includes recovery action numbers, action descriptions, 

recovery priorities, parties responsible2 for funding and/or carrying out actions, duration of 

actions, and estimated costs. Costs are estimated for the fiscal year in thousands of 2016 dollars 

and are not corrected for inflation. The cost estimates do not imply that appropriate levels of 

funding will necessarily be available for all CI beluga recovery tasks. The Implementation 

Schedule (see Section VII) includes annual cost estimates for the first five years of plan 

implementation, in accordance with the standard five-year cycle of review and update or revision

for all recovery plans. Any projections of total costs over the full recovery period are likely to be 

imprecise. The total cost of achieving recovery will be largely dependent upon how many of the 

threats management actions need to be implemented. Since that cannot be determined at this 

time, the total cost presented here assumes that every threat of medium or high relative concern 

will be found to be limiting recovery and that every action addressing those threats will be 

implemented. Thus, we expect the total cost estimate presented here is high, and the actual costs 

will be lower if actions addressing some threats are not implemented because those threats have 

been determined to not be limiting the recovery of CI belugas. It is expected that recovery may 

take at least two generations (50 years); therefore, for ongoing actions costs have only been

estimated for the next 50 years. If every identified recovery action must be implemented, and if it 

takes 50 years to recover CI belugas, then the estimated cost of implementing this entire recovery 

program is approximately $76.8 million (in 2016 dollars).

 

2 Responsible parties have no legal or regulatory obligation to carry out any action. Rather, this is an indication of the entity that 

would most appropriately implement a particular action.
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-1

I. INTRODUCTION

A. The Importance of Belugas to Cook Inlet

Cook Inlet belugas (CI belugas; Delphinapterus leucas), which have co-existed with people 

since the first indigenous hunters and fishermen came to the shores of Cook Inlet, hold an 

important place in both the regional ecosystem and the lives of those who have depended upon 

and interacted with them throughout that long, shared history. Alaska’s Native people have relied 

upon CI belugas for food, other materials, cultural continuity, and community cohesion; indeed, 

there is a significant desire to rebuild a beluga population capable of again supporting 

subsistence use. For the last fifty years the white whales have held a primary position as 

remarkable animals people enjoy living near and observing in Cook Inlet. Apart from the belugas 

found in Canada’s St. Lawrence Estuary (SLE), CI belugas are the only other beluga population 

in the world to live in close proximity to urban centers and to be easily accessed via a road 

system.

Oral histories collected by Dutton et al. (2012) document both the values that today’s 

Alaskans place on living beside these belugas and the opportunities that were lost as the CI

beluga population declined. Visitors to Alaska also enjoy being able to watch belugas in the 

wild. Stories, artwork, the names of streets and businesses all emphasize these belugas’ role 

within our lives and cultures. In addition to their subsistence, cultural, economic (tourism), and 

spiritual values, CI belugas play a role as an indicator of environmental health and resilience in a 

region undergoing considerable natural and human-related change.

This recovery plan represents a significant step in increasing our understanding of the CI 

beluga population and assisting it to rebuild—not just for its own sake or the sake of the 

ecosystem, but also for the sake of future human generations.

B. History of the Listing Status of Belugas in Cook Inlet

In response to the dramatic decline in the population size of the CI beluga stock between 

1994 and 1998, NMFS initiated a status review of CI belugas on November 19, 1998. In early 

1999, NMFS received three petitions: one from Alaska Department of Fish and Game (ADF&G)

to designate CI belugas as depleted under the MMPA and two from tribal and non-governmental 

organizations to list the population as endangered under the ESA. On May 31, 2000, NMFS 

designated the CI beluga stock as below its optimum sustainable population level (OSP)

3 and, 

hence, depleted4 as defined in the MMPA (65 FR 34590). Based on the best scientific data 

available at the time, NMFS determined that the CI beluga stock qualified as a DPS under the 

ESA based on genetic distinction from other Alaskan beluga stocks, but NMFS further 

determined that listing the DPS as endangered or threatened under the ESA was not warranted 

(65 FR 38778, June 22, 2000). 

 

3 Section 3 of the MMPA defines OSP as “the number of animals which will result in the maximum productivity of the population 

or the species, keeping in mind the carrying capacity of the habitat and the health of the ecosystem of which they form a

constituent element” (16 U.S.C 1362(9); see also 50 CFR 216.3). 

4 A species or population is said to be depleted under the MMPA when one of three conditions are met; one of which is when the 

Secretary of Commerce determines that a species or population stock is below its OSP. 
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-2

Concerned that the stock had not recovered as expected, on March 24, 2006, NMFS 

announced its intention to reevaluate the status of the CI beluga under the ESA (71 FR 14836). 

The 2006 status review (Hobbs et al. 2006) drew several significant conclusions about the status 

of the CI beluga. First, the review concluded that the reduced summer range into the upper Inlet 

makes CI belugas far more vulnerable to catastrophic events that have the potential to kill or 

injure a significant portion of the population. Second, the population did not grow as anticipated 

after imposition of subsistence harvest reductions and regulations beginning in 1999 (which 

precluded any harvest in most years), but had continued to decline 4.1% per year from 1999 

through 2006. Third, should this discrete population not survive, it was deemed highly unlikely

that other belugas would repopulate Cook Inlet. Based on models that incorporated the latest data 

available at the time, the 2006 status review predicted a 68% probability that belugas in Cook 

Inlet would continue to decline and become extinct within the next 300 years (with a 26% 

probability of extinction within the next 100 years), unless factors that determine beluga whale 

growth and survival were altered to improve the stock’s chances to recover (Hobbs et al. 2006). 

Based on the findings of the 2006 status review and based on consideration of factors that 

may affect this species, on April 20, 2007, NMFS published a proposed rule to list the CI beluga 

whale DPS as an endangered species under the ESA (72 FR 19854). Subsequently, in April 2008

NMFS completed an updated status review (Hobbs et al. 2008) that supported the conclusions set 

forth in the 2006 report. The April 2008 status review report documented higher probabilities of 

extinction than those presented in 2006; the 2008 modeling showed a 79% probability of 

extinction within 300 years and a 39% probability of extinction within 100 years. On April 22, 

2008, NMFS announced a 6-month extension of the deadline for issuing the final ESA listing 

determination until October 20, 2008, (73 FR 21578) to allow for consideration of the 2008 

abundance estimate. In October 2008, NMFS published a supplemental status review (Hobbs and 

Shelden 2008) which updated the April 2008 review by considering the 2008 CI beluga 

population abundance estimate. The general conclusions of the October 2008 supplemental status 

review were similar to the 2006 and 2008 status reviews; but the inclusion of the 2008 

abundance estimate resulted in a 26% probability of extinction in 100 years and a 70% 

probability of extinction within 300 years.

On October 22, 2008 NMFS issued the final determination to list the CI beluga whale DPS as 

endangered under the ESA (73 FR 62919). This final listing rule included the following 

statements regarding the ESA section 4(a)(1) factors:

A. The present or threatened destruction, modification, or curtailment of its habitat or 

range:

“Concern is warranted about the continued development within and along upper Cook 

Inlet and the cumulative effects on important beluga whale habitat. Ongoing activities 

that may impact this habitat include: (1) continued oil and gas exploration, development, 

and production; and (2) industrial activities that discharge or accidentally spill pollutants 

(e.g., petroleum, seafood processing waste, ship ballast discharge, effluent from 

municipal wastewater treatment systems, and runoff from urban, mining, and agricultural 

areas). Destruction and modification of habitat may result in ‘effective mortalities’ by 

reducing carrying capacity or fitness of individual whales, with the same consequence to 

the population survival as direct mortalities. Therefore, threatened destruction and 

modification of CI beluga whale DPS habitat contributes to its endangered status.” (73 

FR 62927)
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-3

B. Overutilization for commercial, recreational, scientific, or educational purposes:

“A brief commercial whaling operation existed along the west side of upper Cook Inlet 

during the 1920s, where 151 belugas were harvested in five years (Mahoney and 

Sheldon, 2000). There was also a sport (recreational) harvest for beluga whales in Cook 

Inlet prior to enactment of the Marine Mammal Protection Act (MMPA) in 1972. It is 

possible that some residual effects for this harvest may remain and may be a factor in the 

present status of this stock. 

Alaska Natives have legally harvested CI beluga whales prior to and after passage of the 

MMPA in 1972. The effect of past harvest practices on the CI beluga whale is significant. 

While subsistence harvest occurred at unknown levels for decades, the observed decline 

from 1994 through 1998 and the reported harvest (including estimates of whales which 

were struck but lost, and assumed to have perished) indicated these harvest levels were 

unsustainable. Annual subsistence take by Alaska Natives during 1995 to 1998 averaged 

77 whales (Angliss and Lodge 2002). The harvest was as high as 20% of the population 

in 1996. Subsistence removals reported during the 1990s are sufficient to account for the 

declines observed in this population and must be considered as a factor in the proposed 

classification of the CI beluga whale DPS as endangered.” (73 FR 62927)

C. Disease or predation:

“Killer whales are thought to take at least one CI beluga per year (Shelden et al., 2003). 

The loss of more than one beluga whale annually could impede recovery, particularly if 

total mortality due to predation were close to the recruitment level in the DPS.” (73 FR 

62927)

D. The inadequacy of existing regulatory mechanisms:

“Cook Inlet beluga whales are hunted by Alaskan Natives for subsistence needs. The 

absence of legal authority to control subsistence harvest prior to 1999 is considered a 

contributing factor to the CI beluga whale DPS’s decline. NMFS promulgated regulations 

on the long-term subsistence harvest of CI beluga whales on October 15, 2008 (73 FR 

60976). These regulations constitute an effective conservation plan regarding Alaska 

Native subsistence harvest, but they are not comprehensive in addressing the many other 

issues now confronting CI beluga whales. At present, regulations cover the short-term 

subsistence harvest.” (73 FR 62928)

E. Other natural or manmade factors affecting its continued existence:

“Cook Inlet beluga whales are known to strand along mudflats in upper Cook Inlet, both 

individually and in number. The cause for this is uncertain, but may have to do with the 

extreme tidal fluctuations, predator avoidance, or pursuit of prey, among other possible 

causes. We have recorded stranding events of more than 200 CI beluga whales. Mortality 

during stranding is not uncommon. We consider stranding to be a major factor 

establishing this DPS as endangered.” (73 FR 62928)

The MMPA requires the Secretary of Commerce to prepare a Conservation Plan for any 

species or stock designated as depleted under the MMPA and for which NMFS has management 

responsibility. In October 2008, NMFS finalized the Conservation Plan for the Cook Inlet 

Beluga Whale (NMFS 2008a), which reviewed and assessed the known and possible threats to

CI belugas. The Conservation Plan listed natural threats (including stranding events, predation, 
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-4

parasitism, disease, and environmental change) and potential human-caused threats (including

subsistence harvest, poaching, fishing, pollution, vessel traffic, tourism and whale watching, 

coastal development, noise, oil and gas activities, and scientific research). In addition to 

identifying and assessing threats, the Conservation Plan also defined strategies for restoring the 

CI belugas to OSP and identified specific conservation actions to aid in that effort. The goal of 

the Conservation Plan is to conserve and restore the CI beluga whale population to its minimum 

OSP of 780 whales. NMFS has been working with its partners to implement conservation actions 

identified in the Conservation Plan, and has continued to use that document as a guide for 

conserving CI belugas. The Conservation Plan remains in effect, insofar as it covers efforts to 

rebuild the CI beluga stock to the point that it is no longer considered depleted under the MMPA 

(which in some cases may not be synonymous with no longer being listed under the ESA).

Appendices IX.A and IX.B provide more information regarding federal actions, regulations, 

and existing protective measures and conservation efforts pertaining to CI belugas. Existing 

conservation efforts have not been sufficient for CI belugas since the population has continued to 

decline.

C. Designation of Critical Habitat for CI Belugas

On April 11, 2011, NMFS published a final rule designating two areas (minus an exclusion 

zone) of Cook Inlet as critical habitat for the CI beluga (76 FR 20180; 50 CFR part 226.220).

These two areas encompass 7,800 square kilometers (km2

) (3,013 square miles [mi2]) of marine 

habitat (Figure 1).

In designating critical habitat, NMFS evaluated physical and biological features essential to 

the conservation of the species and which may require special management considerations or 

protection. Under NMFS regulations, these features may include: 1) space for individual and 

population growth, and for normal behavior; 2) food, water, air, light, minerals, or other 

nutritional or physiological requirements; 3) cover or shelter; 4) sites for breeding, reproduction, 

rearing of offspring, germination, or seed dispersal; and generally 5) habitats that are protected 

from disturbance or are representative of the historic geographical and ecological distributions of 

the species. Based on the best scientific data available of the ecology and natural history of CI 

belugas and their conservation needs, NMFS determined the following physical or biological 

features are essential to the conservation of this species:

1. Intertidal and subtidal waters of Cook Inlet with depths less than 30 feet mean lower low 

water (9.1 m) and within 5 mi (8 km) of high and medium flow anadromous fish streams.

2. Primary prey species consisting of four species of Pacific salmon (Chinook, sockeye, 

chum, and coho), Pacific eulachon, Pacific cod, walleye pollock, saffron cod, and 

yellowfin sole.

3. Waters free of toxins or other agents of a type and amount harmful to CI beluga whales.

4. Unrestricted passage within or between the critical habitat areas.

5. Waters with in-water noise below levels resulting in the abandonment of critical habitat 

areas by CI beluga whales.

The critical habitat areas are bounded on the upland by the Mean High Water (MHW) line, 

except for the lower reaches of specific tributary rivers. Critical habitat does not extend into the 
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-5

tidally influenced channels of tributary waters of Cook Inlet, with the exceptions noted in the 

descriptions of each critical habitat area.

D. Recovery and Recovery Plans

Section 4(f) of the ESA requires the preparation and implementation of recovery plans for all 

listed species with certain exceptions. Under the ESA, each recovery plan must contain at a 

minimum:

• A description of such site-specific management actions as may be necessary to achieve 

the plan’s goal for the conservation and survival of the species;

• Objective, measurable criteria that, when met, would result in a determination that the 

species be removed from the list; and

• Estimates of the time required and the cost to carry out those measures needed to achieve 

the plan’s goal and achieve intermediate steps toward that goal.

In addition, the Interim Endangered and Threatened Species Recovery Planning Guidance

developed by NMFS (NMFS 2010) stipulates that recovery plans must include a concise 

summary of the current status of the species and its life history, and an assessment of the factors 

that led to the population decline and/or which are impeding recovery. It is also important that 

the plan includes a comprehensive monitoring and evaluation program for NMFS to gauge 

effectiveness of recovery measures and overall progress toward recovery. The overall goal of a 

recovery plan is to guide efforts that achieve recovery of the species such that it may be removed 

from the List of Endangered and Threatened Wildlife (50 CFR 17.11).

While similar in content, recovery plans under the ESA and conservation plans under the 

MMPA do not necessarily have the same end goal. As discussed later, the goal of recovery plans 

is to aid in species’ recovery such that ESA protection is no longer needed. The goal of MMPA 

conservation plans is to aid in the status of depleted population being upgraded so they are no 

longer considered “depleted.”

E. The Recovery Plan for CI Belugas

It is challenging to identify the most immediate needs for recovery of CI belugas because 

little is known about the effects of potential threats to recovery of this population. The 

documented decline of the CI beluga population during the mid-1990s has been attributed to 

subsistence harvest removals at a level that this small population could not sustain (65 FR 34590, 

May 31, 2000; NMFS 2008a, 2008b). NMFS and subsistence users dramatically reduced 

subsistence takes; such a reduction should have allowed the CI beluga population to rebound if 

subsistence harvest was the only factor preventing population growth. However, abundance data 

collected since 1999 indicate that the population is not increasing as expected. It is unknown 

what specific factor(s) continue to limit growth and recovery of this population. It may be that 

the cumulative impacts of several threats are impeding recovery to a greater extent than the sum 

of the individual impacts of those threats.

This plan addresses each of the potential threats based on our current knowledge. In addition 

to examining threats, this plan provides background information on CI beluga life history, status, 

and existing protective measures. Furthermore, this plan identifies a strategy, goals, criteria, and 

actions targeted at recovering the species. Priorities and estimated costs for the recovery actions 

are provided in an implementation schedule.
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-6

Source: NMFS Alaska Region Cook Inlet Beluga Whale Critical Habitat webpage at: http://www.alaskafisheries.noaa.gov/pr/cib-critical-habitat.

Figure 1. CI beluga critical habitat (76 FR 20180, April 11, 2011).
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-7

The recovery actions recommended in this plan are based on the best available science at the 

time the plan was written. Research and monitoring are key components of the plan and will 

make an adaptive management approach possible. Recovery of CI belugas will require a longterm cooperative effort that will evolve as more is learned from research and monitoring. 

Continued monitoring of the status of the population will assist in evaluating the effectiveness of 

management actions. Research will help refine recovery actions and identify new actions to fill 

data gaps about the threats. An adaptive management approach will also provide information to 

adjust priorities as recovery progresses, and will allow the plan to be periodically modified and 

updated.

The process NMFS used to develop a recovery plan for CI belugas is discussed in Appendix 

IX.C.

F. Section Summary: Introduction

ESA Listing Status

In response to a decline in the CI beluga population between 1994 and 1998, NMFS was 

petitioned to designate CI belugas as depleted under the MMPA and/or as endangered under the 

ESA. In 2000, NMFS designated CI belugas as depleted under the MMPA, but determined that 

listing CI belugas as endangered or threatened under the ESA was not warranted at that time.

NMFS later reevaluated the status of CI belugas and, in 2008, listed the CI beluga whale distinct 

population segment (DPS) as endangered under the ESA. Throughout the recovery plan, the term 

“CI beluga population,” “CI belugas,” and “CI beluga whales” refer to the CI beluga whale DPS.

In listing the CI beluga whale DPS as endangered, NMFS referenced the five factors set forth 

in section 4(a)(1) of the ESA: 1) the present or threatened destruction, modification, or 

curtailment of its habitat or range; 2) overutilization for commercial, recreational, scientific, or 

educational purposes; 3) disease or predation; 4) the inadequacy of existing regulatory 

mechanisms; and 5) other natural or manmade factors affecting its continued existence.

The ESA listing of CI belugas as endangered led to the 2011 designation of their critical 

habitat. The ESA requires all federal agencies to consult with NMFS regarding any action they 

authorize, fund, or carry out to ensure that the action does not jeopardize the continued existence 

of the species or result in the destruction or adverse modification of designated critical habitat. 

Recovery Plan for CI Belugas

This Recovery Plan for the Cook Inlet Beluga Whale begins with background information on 

CI beluga life history, population size and trends, and known sources of mortality or injury. It 

then discusses the current threats to the population’s recovery, and presents the recovery 

strategy, goals, and criteria. It concludes with the recovery program, which includes recovery 

actions and an implementation schedule containing priorities and estimated costs for the actions.
Cook Inlet Beluga Whale I. INTRODUCTION

Recovery Plan

I-8

This Page Intentionally Blank
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan A. Physical Habitat of Cook inlet

II-1

II. BACKGROUND

A. Physical Habitat of Cook Inlet

Cook Inlet is a semi-enclosed tidal estuary located in southcentral Alaska (Figure 2). The 

Inlet is approximately 370 kilometers (km) (230 miles [mi]) in length and extends in a 

northeast/southwest orientation from Knik and Turnagain Arms in the north to the southernmost 

reaches of Kamishak Bay in the south (Figure 2). Cook Inlet covers 20,000 km2 (12,427 mi

2

) and 

has 1,350 km (839 mi) of coastline (Rugh et al. 2000). The Cook Inlet watershed includes 

approximately 98,000 km2 (60,894 mi2

). The Susitna River occupies the largest drainage basin 

(50,800 km2, 31,566 mi2), followed by the Matanuska (5,670 km2, 3,523mi2), Knik, 

Chakachatna, and Kenai rivers (each exceeding 2,500 km2, 1,553 mi2).

The bathymetry of Cook Inlet is varied and consists of shoals, canyons, and mudflats (Figure 

3). Cook Inlet is generally shallow, with most waters less than 73 meters (m) (240 feet [ft]) deep. 

However deeper waters exist along the channels and at the entrance to the Inlet near the Barren 

Islands, where depths range from 183–366 m (600–1200 ft; Mulherin et al. 2001). During low 

tides, large areas along the shoreline are exposed as mudflats in Knik Arm, Turnagain Arm, 

Chickaloon Bay, Redoubt Bay, Trading Bay, Kachemak Bay, and the Susitna River Delta. In 

other areas of Cook Inlet, bottom sediments consist of cobbles, pebbles, sand, and clay, with 

occasional patches of boulders or coal seams. Areas with stronger currents associated with 

constrictions in Cook Inlet’s width tend to have coarser bottom sediments.

The physical oceanography of Cook Inlet is characterized by a net inflow along the eastern 

boundary and a net outflow along the western boundary (Burbank 1977). A major inflow is the 

Alaska Coastal Current, a current driven by wind and water densities that flows along the 

southern coast of Alaska and passes through Kennedy Entrance (Figure 4). Upon entering lower 

Cook Inlet, the Alaska Coastal Current turns west just north of Anchor Point, mixing with 

western boundary outflow (Burbank 1977, Muench et al. 1978). A significant component of the 

water along the western boundary originates from Turnagain and Knik Arms, the Susitna River, 

and numerous other glacial streams. In the lower Inlet, this outflow is typically more turbid than 

the water further east due to the heavy glacial runoff from these drainages (Figure 3). These 

sources deposit considerable sediment into Cook Inlet, creating a highly turbid, low visibility 

environment, particularly in the northern portion of the Inlet. Seasonal stream discharges and 

sediment transports typically peak in July to August. In the upper Inlet, summer surface 

temperatures are about 10 degrees Celsius (

o

C) (50 degrees Fahrenheit [oF]) with salinities less 

than 20 parts per thousand (ppt). During summer in the lower Inlet, a relatively warm (10o

C, 

50oF), low salinity (less than 29 ppt), surface layer forms along the west side and a cooler (9oC, 

48oF), higher salinity (greater than 30 ppt) layer forms along the east side.

Cook Inlet experiences some of the greatest tidal fluctuations in the world (Mulherin et al. 

2001). The difference between high and low tide levels may reach 12 m (39 ft). These large tidal 

ranges, combined with broad tidal flats, can result in currents reaching 6.2 meters per second 

(20.3 feet per second), sometimes causing significant changes to shorelines (Moore et al. 2000). 

Three distinct convergence zones, known as tide rips, have been identified in the Inlet (Figure 4). 

The east rip is typically located 2–3 km (1.2–1.9 mi.) offshore of the eastern shore. The west and 

mid-channel rips are located just east of Kalgin Island, and are associated with a 50–80 m (164–262 

ft) deep channel running north to south (Figure 4).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan A. Physical Habitat of Cook inlet

II-2

Source: Map created by NMFS 2013.

Figure 2. Major streams and rivers flowing into Cook Inlet.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan A. Physical Habitat of Cook inlet

II-3

Source: MODIS true color image, acquired 2 September 2002; Okkonen 2005.

Figure 3. Glacial input into Cook Inlet.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan A. Physical Habitat of Cook inlet

II-4

Source: Burbank 1977.

Figure 4. Cook Inlet bathymetry and locations of major tide rips.

In winter, ice covers much of upper Cook Inlet. Rivers begin to freeze in October and 

November and waters of upper Cook Inlet contain persistent ice by December. Large amounts of 

freshwater entering Knik and Turnagain Arms contribute to relatively high ice concentrations in 

the upper Inlet. South of the Forelands, small floes of open pack ice are typical. Maximum ice 

extent is typically reached in late January. Inlet circulation and winter winds tend to move the ice 

south down the west side of the Inlet. Ice breakup in the Inlet typically begins between March 

and May. 

The physical environment of Cook Inlet is shifting towards increasingly long ice-free seasons

as Alaska undergoes climate change. Alaska has experienced the greatest warming of any region 

in the United States (U.S.) (Karl et al. 2009) and Cook Inlet’s reduction in duration of seasonal 

sea ice is consistent with other portions of the state. Alaska’s regional warming is part of a larger 

Arctic-wide warming trend (ACIA 2004; IPCC 2013) that is projected to increase over time.

Middle

rip

East

rip

Kennedy Entrance

Stevenson Entrance

Cook Inlet

Depth

154o 153o 152o 151o 150o 149o

Kalgin

Island

Anchorage

Kenai River

Susitna River

Anchor Pt.

N

Gulf of Alaska

West

rip

Knik Arm

Turnagain Arm

Alaska Coastal

Current

Middle Kasilof River

rip

East

rip

Kennedy Entrance

Stevenson Entrance

Cook Inlet

Depth

154o 153o 152o 151o 150o 149o

Kalgin

Island

Anchorage

Kenai River

Susitna River

Anchor Pt.

N

Gulf of Alaska

West

rip

Knik Arm

Turnagain Arm

Alaska Coastal

Current

Kasilof River
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-5

B. Natural History of CI Belugas

1. Physical Description of Belugas

The beluga (Delphinapterus leucas), or “white whale,” is a small odontocete (toothedwhale). Known for the striking white coloration of the adults, the word “beluga” is derived from 

the Russian word for white, and the specific name leucas is the Latin word for white. The Latin

“apterus” refers to the lack of a dorsal fin, another prominent characteristic. Belugas have a 

stocky body, flexible neck, small rounded head, short beak, and conical teeth. The flippers are 

relatively small but broad and spatulate with edges that tend to curl with age. Their flukes are 

broad and notched with convex trailing edges. Physical characteristics that distinguish belugas

from most other cetaceans include unfused cervical vertebrae accompanied by increased head 

mobility, a very bulbous flexible melon in the forehead region, the lack of a dorsal fin, and 

presence of a tough dorsal ridge. Belugas are relatively slow swimmers that often roll slowly at 

the surface, and their blow is often inconspicuous.

Calves are born dark gray to brownish gray and become lighter colored with age. Adults may 

become white to yellow-white at sexual maturity, although Burns and Seaman (1986) report 

females may retain some gray coloration for as long as 42 years (assuming one dentinal layer per 

year). McGuire et al. (2008) reported several photo-identified mothers that were still gray when 

they had calves, suggesting that coloration is not a definitive indicator of maturity. Beluga 

researchers commented that the gray belugas they observed in Cook Inlet (during August 2016) 

appeared larger than the gray belugas found in the St. Lawrence Estuary (R. Michaud, GREMM, 

pers. comm. to Mandy Migura, NMFS).

Belugas are sexually dimorphic, with length averaging 355 centimeters (cm) (11.6 ft) in adult 

females and 415 cm (13.6 ft) in adult males (Burns and Seaman 1986). Males weigh up to 1,500 

kg (3,307 pounds [lb]) and females 1,360 kg (2,998 lb) (Nowak 1991). Beluga calves in Alaska 

have been reported to average 150 cm (4.9 ft) in length and 72 kg (159 lb) at birth (Burns and 

Seaman 1986

2. Taxonomy, Geographic and Genetic Variation

The beluga is a member of the Monodontidae, the taxonomic family it shares with the 

narwhal. The earliest fossil record of the Monodontids is an extinct beluga (Denebola 

brachycephala) from late Miocene deposits in Baja California, Mexico, indicating that this 

family once occupied temperate ecozones (Barnes 1984). Fossils of belugas found in Pleistocene 

clays in northeastern North America reflect successive range expansions and contractions of this 

species associated with glacial maxima and minima. The beluga is a northern hemisphere 

species, ranging primarily over the Arctic Ocean and some adjoining seas and inhabiting fjords, 

estuaries, and shallow waters in Arctic and subarctic oceans, except for a small population in the 

Gulf of St. Lawrence, Canada. Some belugas seek out shallow coastal waters in summer and 

remain near the ice edge in winter. In Alaska, there are five recognized beluga stocks (Figure 5)

delineated based on summer range: the Beaufort Sea, eastern Chukchi Sea, eastern Bering Sea, 

Bristol Bay, and Cook Inlet stocks (Allen and Angliss 2012). Murray and Fay (1979) suggested 

the CI beluga stock has been isolated from the other stocks for several thousand years. The lack 

of CI beluga observations along the southern side of the Alaska Peninsula (Laidre et al. 2000) 

and genetic data (O’Corry-Crowe et al. 1997, 2002, 2010) have corroborated Murray and Fay’s 

(1979) suggestion of distinction from the other stocks.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-6

Source: NMFS 2008a.

Figure 5. Map of summer distributions of the beluga stocks in Alaska.

Sightings of belugas in the Gulf of Alaska are rare outside of Cook Inlet (Laidre et al. 2000). 

The degree of genetic differentiation between the Cook Inlet stock and the other four Alaska 

beluga stocks indicates the Cook Inlet stock is the most isolated (O’Corry-Crowe et al. 1997, 

2002, 2010). This suggests that the Alaska Peninsula has long been an effective physical barrier 

to genetic exchange and that migration of whales into Cook Inlet from other stocks is unlikely. 

The exception to the rarity of belugas in the Gulf of Alaska outside of Cook Inlet may be a 

very small group of belugas that appear to reside year-round in Yakutat Bay (Fiscus et al. 1976; 

Consiglieri and Braham 1982; Hansen and Hubbard 1999; O’Corry-Crowe et al. 2006). Genetic 

samples collected from whales in Yakutat Bay are more closely related to each other than they 

are to whales sampled in other areas of Alaska (O’Corry-Crowe et al. 2006), and are unlikely to 

represent whales traveling from the Cook Inlet population. Since there is no evidence of 

interaction between CI belugas and belugas found in other areas of the Gulf of Alaska, including 

the Yakutat Bay area, this recovery plan focuses only on the belugas inhabiting Cook Inlet. 

3. Beluga Distribution in Cook Inlet

Data on distribution and habitat use comes primarily from two main sources: aerial surveys 

(Hansen and Hubbard 1999; Speckman and Piatt 2000; Rugh et al. 2010; Shelden et al. 2015b) 

and satellite transmitter tagging studies during August through March (Hobbs et al. 2005). 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

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Additional information is provided by traditional ecological knowledge (TEK) of Alaska Natives 

(e.g., Huntington 2000; Braun and Huntington 2011; Carter and Neilsen 2011), boat and landbased observations (e.g., McGuire and Bourdon 2012; Brueggeman et al. 2013), passive acoustic 

monitoring studies (e.g., Small 2011), opportunistic reports (e.g., Rugh et al. 2000; VateBratstrom et al. 2010; Shelden et al. 2015b; NMFS, unpub. data), NMFS stranding records (e.g., 

Vos and Shelden 2005; NMFS, unpub. data), and data from a citizen science CI beluga sighting 

project (Švarný Carlson et al. 2015). 

Localized information on distribution and habitat use of specific areas of Cook Inlet is 

available from studies conducted in conjunction with the development activities, universities, or 

other entities. Some of the available data sources are associated with: the Port of Anchorage 

Expansion Project; Ocean Renewable Power Company’s Fire Island Tidal Project; Pac-Rim 

Coal’s Chuitna Coal Project; Cook Inlet Region Inc.’s Fire Island Wind Project; the Alaska 

Department of Transportation’s Seward Highway Expansion Project; the Port MacKenzie 

Expansion Project; the Knik Arm Bridge and Toll Authority’s (KABATA) Knik Arm Crossing; 

the Alaska Communication System’s Fiber Optic Cable Project; seismic programs for Apache 

Alaska, ConocoPhillips Alaska, and Furie/Escopeta Oil; Joint Base Elmendorf Richardson’s CI 

beluga studies program; and LGL’s CI beluga Photo-Identification Project. Many of these 

projects’ reports may be found on the NMFS AKR website at:

http://www.alaskafisheries.noaa.gov/pr/ci-belugas.

a. Distribution Patterns: 1970s, 1990s, and 2000s

The distribution of CI belugas has changed significantly since the 1970s, when aerial surveys 

for belugas in Cook Inlet were first conducted. ADF&G conducted aerial surveys of Cook Inlet 

in June and July in the late 1970s. These surveys were limited in scope and involved a single 

sample of a portion of Cook Inlet. While many of the early reports lacked sufficient descriptions 

of how and where the surveys occurred, good documentation is available for aerial surveys 

conducted on 18 June 1978 and 18–22 June 1979 (ADF&G, unpub. data). Beginning in 1993 

NMFS started conducting comprehensive surveys annually (with the exception of 2013 when 

surveys were switched to a biennial schedule) during a 1- to 2-week period each year, with 3–7 

repetitions of coastal flights around the upper Inlet plus 1–2 days dedicated to a survey of the 

lower Inlet (Rugh et al. 2000, 2005a,b; Hobbs et al. 2015a; Alaska Fisheries Science Center, 

Marine Mammal Laboratory [AFSC MML], unpub. data).5

Rugh et al. (2010) used three time periods to examine changes in historical distribution 

patterns of CI belugas: late 1978 to 1979 (when well-documented data are available; Figure 6); 

1993 to 1997 (during a decline in abundance; Figure 7); and 1998 to 2008 (when hunting was 

regulated and recovery was anticipated; Figure 8). This analysis of aerial survey data showed

that the extent of the late spring/early summer distribution (June/July) of CI belugas has changed 

considerably since the late 1970s. The whales were distributed over a relatively large area in 

1978 and 1979, with the central location of the summer range occurring between the McArthur 

and Beluga rivers (Figure 6). The area of highest concentration included the region from Drift 

River to the Susitna Delta. The TEK also indicated that CI belugas had long been observed in the 

 

5 For more information, contact the NMFS AFSC MML, Cetacean Assessment and Ecology Program.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-8

lower Inlet, including Kachemak Bay on the eastern side and Tuxedni and Trading Bays on the 

western side, although rarely in large numbers (Huntington 2000; Braund and Huntington 2011). 

From 1993 to 1997, the central location of the summer range shifted northeast to the mouth of 

the Susitna River and the area of highest concentration contracted to a region north of Moose 

Point (Figure 7). From 1998 to 2008, the central location of the summer range shifted east, then 

occurring between the Little Susitna River and Fire Island (Figure 8); the area of highest 

concentration included Knik Arm and Chickaloon Bay (between Point Possession and Turnagain 

Arm). Changes in distribution over the three time periods were significant. These include the 

northeast contraction of the summer range of belugas into upper Cook Inlet from the 1970s to the 

1990s and into the 2000s, as well as a longitudinal shift east toward Anchorage between 1993 

and 2008. Core summer distribution was estimated to have contracted from over 7,000 km2

(2,703 mi2) in 1978 to 1979, to 2,800 km2 (1,081 mi2) in 1998 to 2008 (Rugh et al. 2010). 

Subsequent to this analysis, Shelden et al. (2015b) compared the core summer distributions

reported for the three time periods examined by Rugh et al. (2010) (Figures 6, 7, 8) with the core 

summer distribution of CI belugas observed in 2009 to 2014 (Figure 9). In this more recent time 

period, the core summer distribution (estimated area = 1,787 km2) continued to contract 

northward, while remaining centered on the Susitna Delta (Figure 9). Fewer sightings of CI 

belugas in lower Cook Inlet in recent decades (Hansen and Hubbard 1999; Speckman and Piatt 

2000; Rugh et al. 2000, 2004, 2010) also indicate that the summer range of CI belugas has 

contracted to the mid and upper Inlet, coincident with their decline in population size.

The reason for this change of distribution is not known, but several hypotheses have been 

proposed, including: 1) an effect of changing habitat, such as through diminished prey 

availability (Moore et al. 2000); 2) avoidance of killer whales (Shelden et al. 2003); and 3) 

preference and ability of this remnant population to remain in preferred habitat areas due to 

reduced intra-specific competition as a result of a reduction in population size (Goetz et al. 

2007). Regardless of the reason, the result of the CI beluga range contraction brings animals in a 

small range proximal to Anchorage during summer months, where there is increased potential for 

disturbance from human activities. 

b. Seasonal Distribution Patterns

Multiple data sources indicate that belugas exhibit seasonal shifts in distribution and habitat 

use within Cook Inlet, however, belugas in Cook Inlet do not migrate out of Cook Inlet. The 

known seasonal shifts in distribution of CI belugas appear to be related to seasonal changes in 

the physical environment (e.g., ice and currents) and to shifts in food sources, specifically the 

timing of fish runs. Generally, CI belugas spend the ice-free months in the upper Inlet (often at 

discrete high-use areas), then expand their distribution south and into more offshore waters of the 

middle Inlet in winter (Hobbs et al. 2005), although they may be found throughout the Inlet at 

any time of year. These seasonal patterns have been long observed and utilized by subsistence 

hunters (Huntington 2000), and as reviewed by Shelden et al. (2015b), have more recently been 

documented by aerial surveys (Rugh et al. 2000, 2004), satellite telemetry (Ferraro et al. 2000; 

Hobbs et al. 2005), and during shore and boat-based observations (e.g., Funk et al. 2005; 

McGuire and Bourdon 2012; McGuire et al. 2014a). Most recently, passive acoustic monitoring 

is being used to assess seasonal movements throughout the Inlet (Lammers et al. 2013; Castellote 

et al. 2016a).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-9

Source: Rugh et al. 2010.

Figure 6. Areas occupied by belugas in Cook Inlet, Alaska, in June/July 1978 to 1979.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-10

Source: Rugh et al. 2010.

Figure 7. Areas occupied by belugas in Cook Inlet, Alaska, in June/July 1993 to 1997.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

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Source: Rugh et al. 2010.

Figure 8. Areas occupied by belugas in Cook Inlet, Alaska, in June 1998 to 2008.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-12

Source: Shelden et al. 2015b.

Figure 9. Areas occupied by belugas in Cook Inlet, Alaska, in June 2009 to 2014.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-13

Movement data are available from 14 CI belugas tracked for variable periods of time (2–240 

days) with satellite transmitters between May 1999 and March 2003. Tags attached to nine 

whales logged movements from August or September into December, with four continuing to 

transmit movement data into the following March (Hobbs et al. 2005; Goetz et al. 2012a; 

Shelden et al. 2015b). All tagged CI belugas remained within Cook Inlet for the period they were 

tracked. Whales spent the summer and early fall months in the upper Inlet, concentrating at river 

mouths. Within this time period, whales often made weekly movements between the mouth of 

the Little Susitna River, Knik Arm, Turnagain Arm, and Chickaloon Bay. During the late 

summer the belugas remained in the upper Inlet, centered in Knik Arm (Figures 10a, 10b). 

During the fall, the belugas concentrated in Chickaloon Bay and areas of the west side near 

Tyonek (Figures 10c, 10d). In late fall, tagged whales began to make more extensive movements 

south into the middle Inlet and into deeper offshore waters (Figure 10e), and were not found in 

the large dense groups commonly seen in the summer months (Rugh et al. 2004). This pattern 

continued through winter (Figures 10f–10h), when whales exhibited the most wide-ranging 

movements, spanning both nearshore and offshore waters from the upper reaches of Knik Arm to 

the middle Inlet.

Several other observational studies have been conducted which contribute to our 

understanding of CI belugas’ seasonal movements. A year-round shore and boat-based 

observational study in Knik Arm (July 2004 to July 2005) revealed seasonal patterns in habitat 

use and abundance of this area, with peak abundances in fall (September) declining to lowest 

numbers in winter, and highest use of river mouths and mud flats (Funk et al. 2005). Shore-based 

studies during the ice-free months along Turnagain Arm found peak beluga abundances midAugust through October, with whales occasionally present mid-April to early May (Markowitz 

and McGuire 2007; McGuire and Bourdon 2012). An ongoing (2005–present) photoidentification study within the upper Inlet with sighting histories of 376 individual belugas 

(2005–2015; T. McGuire, LGL Alaska Research Associates [LGL], pers. obs.) has documented 

movements by individual whales among several high-use areas within a summer season, 

including Susitna Flats, Knik Arm, Chickaloon Bay, Turnagain Arm (McGuire et al. 2009), and 

the Kenai River (McGuire et al. 2014a). Results from passive acoustic monitoring across the 

entire Inlet (summarized in Section II.B.4. Use of Critical Habitat by Belugas) support seasonal 

patterns observed with other methods (M. Castellote et al., AFSC MML, pers. comm.).

Large aggregations of belugas in specific areas of upper Cook Inlet during May to October 

are presumed to indicate a critical time period for foraging, based on the need to assimilate 

resources for overwinter survival (Calkins 1983; Huntington 2000). It is during the ice-free 

months when calves are born and nursed and when the whales acquire the thick blubber layer 

they will need to survive through the winter months, when anadromous fish runs end and prey 

move to deeper, offshore regions (Hobbs et al. 2005; Hobbs et al. 2008). 

4. CI Beluga Habitat Characteristics and Use

a. CI Beluga Feeding Habitat

CI belugas are frequently seen aggregating near the mouths of rivers and streams, when 

anadromous fish species are present and often at their peak availability (Moore et al. 2000).

These concentrations of belugas within discrete areas of the upper Inlet and offshore of several
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-14

Figure 10a. Figure 10b.

Figure 10c. Figure 10d.

Notes: A single best location was chosen for each day. Predictions derived via kernel probability estimates. Note the large increase in total area 

use and offshore locations beginning in December and continuing through March. The red area (95% probability) encompasses the green (75%) 

and yellow (50%) regions; the yellow area represents the highest density.

Source: Hobbs et al. 2005.

Figure 10 (a–h). Predicted CI beluga distribution by month based on known locations of 14 satellite-tagged 

belugas.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-15

Figure 10e. Figure 10f.

Figure 10g. Figure 10h.

Figure 10 (a–h). Continued.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-16

important salmon streams are assumed to be the result of a feeding strategy that takes advantage 

of the bathymetry of the area: the fish are funneled into the channels formed by the river mouths,

and the shallow waters act as a gauntlet for fish as they move past waiting belugas. Hazard 

(1988) hypothesized that belugas were more successful feeding in rivers where prey were 

concentrated than in bays where prey were dispersed, implying that CI belugas seek areas where 

anadromous prey escapement (return to freshwater spawning habitat) numbers are high, but also 

areas that have certain habitat features. Research by Frost et al. (1983) on belugas in Bristol Bay 

suggested those whales preferred certain streams for feeding based on the configuration of the 

stream channel. Their study theorized beluga feeding efficiency improved in relatively shallow 

channels where fish were confined or concentrated. Because belugas do not always feed at the 

streams with the largest runs of fish, bathymetry, fish density, and lack of disturbance may be 

more important than sheer numbers of fish in determining their feeding success. For example, CI 

belugas today are seen less frequently at the mouth of the Kenai River than they were 

historically, despite large salmon returns to the river. Whether this is due to changes in prey 

species composition or density, bathymetric changes, increased levels of disturbance, or other 

unknown factors remains a matter of speculation.

Habitat use in the summer months consists of semi-predictable movements of groups of 

belugas between river mouths and shallow tidal flats in the upper Inlet. These movements are 

largely cued to physical conditions, especially tide, but may also be influenced by anthropogenic 

activities. TEK indicates that daily movements are determined by the ebb and flow of the tide 

and the related movements and size of fish runs, and also by the presence of killer whales 

(Huntington 2000). For example, whales often concentrate on the shallow mudflats of the 

Susitna River Delta and Chickaloon Bay at low tide, and may enter upper Inlet rivers on the 

flooding tide, although the reverse tidal pattern has been observed in Eagle River in Knik Arm 

(T. McGuire, LGL, pers. obs.). Observational studies (Funk et al. 2005; Markowitz and McGuire 

2007) and ocean circulation and inundation models, combined with tracks from tagged 

individual whales (Ezer et al. 2008), confirm long-held local knowledge that daily feeding 

movements are influenced greatly by tidal cycle. 

In the fall, as anadromous fish runs begin to decline, belugas consume the fish species found 

in nearshore bays and estuaries; however, some belugas may feed on salmon kelts (spawned fish) 

during this time. Habitat associations of nonanadromous beluga prey species in Cook Inlet 

include preferences for sand and mud substrates (Eschmeyer et al. 1983; Cohen et al. 1990;

ADF&G 2004), and a number of these species move seasonally from shallow to deep water. 

Movements of belugas within the Inlet during the months when anadromous fish runs are not 

present may reflect the seasonal movements of these other prey species. Unlike salmon and 

eulachon, the prey available in winter do not tend to form large concentrations, and it may be 

that belugas tend to disperse throughout the Inlet during November through April, to utilize the

more-dispersed prey (Hobbs et al. 2005). In the winter, CI belugas use deeper waters in the mid 

Inlet past Kalgin Island and make deep feeding dives. The presence of Kalgin Island south of the 

Forelands may create upwelling and eddies which concentrate nutrients and provides a still-water 

refuge area for migrating anadromous fishes (Calkins 1983, 1989). This area may also be a latewinter staging area for eulachon before they return to streams in the upper Inlet. Given the 

unique oceanographic conditions and the diversity of fish and crustaceans found near Kalgin 

Island, this area may be rich in biological productivity, and thus an important winter feeding 

habitat for belugas.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

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Castellote et al. (2016a) obtained information on the seasonal distribution and foraging 

behavior of belugas in Cook Inlet through passive acoustic monitoring of beluga social calls and 

echolocation activity at 13 locations in lower Cook Inlet (Homer, Tuxedni Bay, and Kenai 

River), upper Cook Inlet (Trading Bay, Beluga River, Little Susitna River, and Fire Island), and 

Knik Arm (Point Mackenzie, Cairn Point, Six Mile, South Eagle Bay, Eagle River Mouth, and 

North Eagle Bay) during 2008–2013. Analysis of the echolocation data indicated that foraging 

behavior, as inferred from presumed foraging buzzes, was more prevalent during summer than 

during winter, particularly at upper Inlet rivers. Passive acoustic monitoring was restricted to 

nearshore areas, so offshore foraging was not assessed, and due to a limitation of the study 

methods, foraging on benthic prey may not have been readily detectable.

Goetz et al. (2007, 2012b) used geographic information systems (GIS) to develop 

quantitative models of the summer habitat preferences of CI belugas. Habitat models were used 

to examine ecological relationships among belugas and several environmental variables. 

Parameters used in the models were based on June/July beluga sightings (1993 to 2004) relative 

to available environmental data: 1) bathymetry; 2) mudflats; and 3) flow rates among freshwater 

tributaries entering Cook Inlet. The two quantitative models predicted similar size and location 

of beluga habitat and identified mudflats and river size as important environmental features. 

Belugas are found near mudflats and prefer medium and high flow accumulation areas (i.e., 

medium to large river basins). Although sighting data in this study were collected primarily in 

June, other aerial surveys (Rugh et al. 2000, 2004), shore-based systematic and opportunistic 

observations (Funk et al. 2005; NMFS, AFSC MML, unpub. data), boat-based photoidentification surveys (McGuire and Bourdon 2012), and whales tagged with satellite 

transmitters (Hobbs et al. 2005) show that the distribution documented in June is largely 

representative of the distribution throughout the ice-free months; Knik Arm, Turnagain Arm, 

Chickaloon River, and the Susitna River Delta are used extensively. In fact, belugas occasionally 

access these preferred habitats in winter despite thick ice cover (Hobbs et al. 2005). Tidal 

movement corridors are also important to CI belugas, as beluga movements with the tides may 

occur up to twice daily and allow or limit access to feeding areas (Hobbs et al. 2005; Funk et al. 

2005; Markowitz and McGuire 2007). Access to these areas and to corridors between these areas 

is important to the feeding strategy of CI belugas. 

Additional analyses by Goetz et al. (2012b) concluded that belugas were found in areas of 

high fish availability and access to tidal flats and sandy substrates and that belugas were 

negatively associated with anthropogenic disturbance. These habitat models predicted that 

beluga distribution would include coastal areas extending nearly the entire length of Cook Inlet 

(Goetz et al. 2007), and, historically belugas inhabited large parts of the Inlet, including its 

central and southern reaches (Rugh et al. 2000). However, since 1993, beluga sightings have 

been rare (0–4% of all reported sightings per year) in areas south of the Forelands, and almost all 

sightings have been in the upper Inlet, from the Susitna Delta to Knik Arm and Chickaloon Bay 

(Rugh et al. 2000, 2005a, b). A significantly reduced CI beluga population (Hobbs et al. 2000), 

in combination with beluga preference for estuarine waters with the largest concentration of prey 

species, may explain the current distribution of whales, but data on relative densities of fish by 

species and season are not available to test this hypothesis. 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

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b. CI Beluga Calving Habitat

In addition to being important feeding habitats, the shallow waters of the upper Inlet may 

also play important roles in reproduction. Since newborn belugas do not have the thick blubber 

layer of adults, they may benefit from the warmer water temperatures in the shallow tidal flats 

areas where fresh water empties into the Inlet, and it is likely these regions are used as nursery 

areas (Katona et al. 1983; Calkins 1989). These shallow areas may also provide refuge from 

killer whale predation on calves. The TEK of Alaska Natives has described historical beluga 

calving and nursery habitats as the northern side of Kachemak Bay, the mouths of the Beluga 

and Susitna Rivers, as well as Chickaloon Bay and Turnagain Arm (Huntington 2000). Knik 

Arm is also used extensively in the late summer and fall by cow/calf pairs: Funk et al. (2005) 

noted a relatively high representation of calves in the uppermost part of Knik Arm; the mouth of 

Knik Arm has been reported to be transited in the summer and fall by cow/calf pairs (Cornick 

and Kendall 2008); and groups seen in Eagle Bay usually contain calves (McGuire and Bourdon 

2012). 

Because calving events have not been documented in Cook Inlet, specific calving grounds 

have not been identified, although it seems likely that the areas identified as nursery areas might 

also serve as calving grounds. Based on the presence of calves sighted in summer aerial surveys, 

Calkins (1983) speculated that calving might occur in the larger estuaries of upper western Cook 

Inlet. During boat-based surveys for calves conducted in 2007 to 2011, the first neonates (i.e., 

newborns) of the season were seen at the Susitna River Delta (McGuire and Bourdon 2012). 

Later in the season, groups seen in Knik Arm were more likely to contain neonates than groups 

in other areas. Distinct areas for neonate and calf rearing were not identified, as calves and 

neonates were seen in all locations surveyed in upper Cook Inlet (the Susitna River Delta, Knik 

Arm, Chickaloon Bay/Southeast Fire Island, and Turnagain Arm). McGuire et al. (2016) 

reported that during photo-identification surveys conducted in upper Cook Inlet (2005 to 2015)

and the Kenai River Delta (2011 to 2013), the first neonates seen each survey year were located 

in the waters of the Susitna River Delta. Neonates were seen later in the season in all other 

survey areas where belugas were encountered (i.e., the Susitna River Delta, Knik Arm, 

Chickaloon Bay, Turnagain Arm, and the Kenai River). McGuire et al. (2016) also documented 

the birth of a CI beluga in the Susitna River Delta. Based on these data, they suggested the

Susitna River Delta should be considered a calving ground for CI belugas, and the nearshore 

waters of upper Cook Inlet should be considered CI beluga nursery grounds.

c. Other Uses of Habitat

Other important uses of habitat by CI belugas may include avoidance/escape from predators, 

transiting among feeding and/or nursery habitats, refuge from human activities (e.g., in-water 

noise, ship traffic, and hunting), and molting. In the 2008 Conservation Plan (NMFS 2008a), 

NMFS stated that warmer, fresher coastal waters may be important areas for belugas’ seasonal 

summer molt (Finley 1982) and that shallow waters may provide conditions necessary to help 

facilitate the shedding of dead skin and regeneration of epidermal layers. However, eight years of 

photographic records of over 303 individual CI belugas photographed from April to November 

do not display signs of obvious molting; it may be that molting in CI belugas is a more diffuse, 

gradual process than it is for those beluga stocks found in more northern latitudes and that habitat 

specifically for seasonal molting is not required for CI belugas. Molting has also not been 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-19

observed in SLE belugas, despite over 25 years of studies on this population (P. Béland, St. 

Lawrence National Institute of Ecotoxicology, pers. obs.).

d. Human Environment of Cook Inlet

Belugas in Cook Inlet are unique in Alaska given that their habitat is in close proximity to the 

largest urban area in the state with over 60% of the state-wide population. In 2010 (the most 

recent census year available), the population of the State of Alaska was 710,231 people, with 

291,826 in the Municipality of Anchorage, 88,995 in the Matanuska-Susitna Borough, and 

55,400 in Kenai Peninsula Borough.

6 The population in this region has been increasing; between 

1980 and 2010 the population grew by 67%.

7

Belugas are not uniformly distributed throughout Cook Inlet, but are predominately found in 

nearshore waters, adjacent to areas of high human activity. Humans use the waters and shores of 

Cook Inlet for fishing, hunting, recreating, timber harvesting, mining, shipping, dredging, 

renewable energy production, discharge of wastewater, military activities, oil and gas 

development, transportation, and residential and industrial development (Figure 11).

The majority of land in the Cook Inlet Basin is publicly managed by state or federal agencies. 

Native groups and individuals are among the most significant private landowners.

5. Age, Growth, Reproduction, and Survival

Belugas are long-lived and have a relatively slow reproductive cycle, giving birth to a single 

calf every two, three, or more years, and devoting considerable time to caring for their young. 

Although some life history data are available for CI belugas, considerably more data exist for 

other beluga populations (see Table 1). Most general beluga life history data have been obtained 

through measurements and samples of animals taken in subsistence harvests, although some 

information has come from live stranded, dead beach-cast or floating whales, and some from 

captive belugas. Relatively little life history data are available specifically for CI belugas.

To understand growth, reproduction, and survival rates, investigators must determine the age 

structure of the population. Age is primarily assessed by counting the number of growth layer 

groups (GLGs) of teeth in thin longitudinal sections (see Appendix IX.D – CI Beluga Natural 

History Supplement). Historically, it was believed that belugas might live more than 30 years 

(Burns and Seaman 1986); however, it is now thought that belugas may live 60 to 70 years or 

more (Suydam 2009). It is difficult to know the exact age of older belugas because their teeth 

wear down and some GLGs are lost as animals age; therefore it is likely that ages determined by 

counting GLGs are underestimates. For teeth of the 102 CI belugas that have been aged using the 

single GLG method, the oldest CI beluga was estimated to be at least 49 years (Vos 2003; 

NMFS, unpub. data).

8

 

6 Census information obtained from State of Alaska Department of Labor and Workforce Development Census and Geographic 

Information website at: http://live.laborstats.alaska.gov/cen/index.cfm.

7 Census information obtained from U.S. Census Bureau Quickfacts at: http://quickfacts.census.gov/qfd/states/02/0203000.html.

8 For more information, contact NMFS AKR, Protected Resources Division.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-20

Figure 11. General geographic distribution of current and proposed human activities in Cook Inlet, Alaska.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-21

Obtaining information on the age at sexual maturity (ASM) sheds light on reproduction, and 

increasing or decreasing trends in ASM may help determine ecosystem dynamics. For instance, 

if ASM decreases over time in females, this might suggest that resources are not limiting 

population growth. In published literature, estimates of ASM in belugas ranged from 4–14 years 

for females and 8–15 years for males (Braham 1984; Nowak 1991; Heide-Jørgensen and 

Teilmann 1994; Suydam 2009; Table 1). While the cause of the wide range of ASM is currently 

unknown, possible reasons include: 1) animals may mature at different ages among stocks; 2)

different methods may have been used to estimate ages; or 3) the definition of ASM may have 

differed (e.g., age at first ovulation vs. age at first conception vs. age at first birth). Burns and 

Seaman (1986) estimated the age at first conception for 22 female belugas in northeast Alaska to 

be between 8 and 13 years (based on 1 GLG per year).

Estimates of the length of gestation for belugas have also varied from 11 to 16 months (Table 

1), although data from captive belugas where conception and birth are precisely known indicate a 

gestation of 15.6 months (Robeck et al. 2005). Calkins (1983) suggested that most calving in 

Cook Inlet occurs from mid-May to mid-July. Alaska Native hunters have reported calving from 

April through August (Huntington 2000). More recently, observations of neonates during annual 

photo-identification surveys of CI belugas conducted from spring to fall in upper Cook Inlet 

(2005 to 2015) and the Kenai River Delta (2011 to 2013) led McGuire et al. (2016) to conclude 

the peak calving period for CI belugas is mid-July through mid-October. The lactation period for 

belugas is known to last at least a year, and likely longer in some cases. This estimate is based on 

observations of lactating females that are pregnant with a new fetus and with some estimates of 

weaning not occurring for about two years; thus, the entire reproductive process on average takes 

three years (Sergeant 1973; Burns and Seaman 1986). Depending on the age and experience of 

the mother, however, the calving interval may be as short as two years or over three years 

(Suydam 2009). Many studies suggest a calving interval for belugas of approximately three 

years, which equates to a pregnancy rate of about 0.33 per year (Kleinenberg et al. 1969; 

Sergeant 1973; Ognetov 1985; Burns and Seaman 1986; Doidge 1990b; Heide-Jørgensen et 

al.1994). This would indicate that approximately one-third of mature females would be newly 

pregnant in any given year. However, belugas in Hudson Bay, Canada, and Point Lay, Alaska,

had greater pregnancy rates of 0.47 (Hudson Bay; Sergeant 1973; Doidge 1990a) and 0.41 (Point 

Lay; Suydam 2009) indicating calving intervals shorter than three years. Several studies have 

also suggested a decrease in the pregnancy rate (based on studies of the ovaries) as a female 

beluga ages, particularly after 40 years (GLGs) (Brodie 1982; Heide-Jørgensen and Teilmann 

1994; Suydam 2009). Kleinberg et al. (1969; as presented in Brodie 1971) arbitrarily estimated 

age at senescence to be around 42–43 years (GLGs). However, this does not mean that older 

female belugas are not capable of reproducing past this age; a 68 year old female beluga in the 

St. Lawrence Estuary population in Canada showed signs of recent reproductive activity 

(McAlpine et al. 1999 as cited in DFO 2012).

In 2005 NMFS began August calf surveys of Cook Inlet. Calving indices were estimated for 

the period from 2006 to 2012, and indicated that more calves were born by the time the August 

surveys were conducted in 2006 (12%) than in subsequent years 2007 to 2012, when the average 

rate was 1.9% (Hobbs et al. 2015a). These calving indices have several potential biases; 

accordingly, they should be used for trend analysis only, and not for absolute estimates of calf 

production. They indicate considerable variability from year to year so that a much longer time 

series is required to determine an average. A similar observation has been made in the SLE 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-22

Table 1. Review of female beluga life history parameters found in the published literature.

Parameters Data Sources

Age at sexual maturity 9–11 growth layer groups in teeth (GLGs) (mean=10, excluded one 

immature animal age 15 GLGs, sample sizes not provided). 

1

7–13 GLGs (mean=10 GLGs), 5–6 to 11–12 GLGs (mean=9 GLGs, n =

33, calculated from data collected by Khuzin [1961] in the Kara and 

Barents seas, Russia). 

2

0% at 8–9 GLGs, 33% at 10–11 GLGs, 94% at 12–13 GLGs, 100% at 16–

17 GLGs (n = 207). 

3a

9.1 ± 2.8 GLGs (captive beluga studies, n = 23). 4

50% at 8.25 GLGs (n = 87) 15

Age at color change

(gray to white)

12 GLGs (minimum age) 1

14 GLGs (minimum from Mackenzie Delta), 

17 GLGs (minimums from western Hudson Bay)

2

9–10 GLGs for males, 10–12 GLGs for females 15

Age at 1st conception 54% at 8–9 GLGs (n = 12 of 22) 

41% at 10–11 GLGs (n = 9 of 22) 

5% at 12–13 GLGs (n = 1 of 22) 

3

8.27 GLGs (SE = 2.88, n = 87) 15

Age at senescence 42–43 GLGs (arbitrarily assumed by Kleinenberg et al. 1969) 1

40 GLGs (corpora level off and decline) 15

Pregnancy and birth rates With small fetuses: 

0.055 at 0–11 GLGs 

0.414 at 12–21 GLGs 

0.363 at 22–45 GLGs 

0.267 at 46–57 GLGs 

0.190 at 58–77 GLGs 

3

With full–term fetuses or neonates: 

0.000 at 0–11 GLGs 

0.326 at 12–21 GLGs 

0.333 at 22–45 GLGs 

0.278 at 46–51 GLGs 

0.182 at 52–57 GLGs 

0.125 at 58–77 GLGs

3

0.41 (with small fetuses); 0.56 (with full term fetuses or neonates) 15

Lifespan 60–61 GLGs 1

50–53 GLGs 2b

>60 GLGs (oldest female estimated at 70+ GLGs) 3

46 GLGs (male, tooth worn with no visible neonatal line) 15

57 GLGs (female) 15

Adult annual survival 0.9064 (average based on mean annual mortality rate = 0.0936) 3

0.91–0.92 5, 6

0.842 and 0.905 (assuming 2GLGs/yr vs. 1 GLG/yr) 7

0.96–0.97 8
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-23

Parameters Data Sources

0.935 9

Immature annual survival 0.905 (for neonates in first half year of life, mortality rate=0.095) 2

0.955 (based on pilot whale net recruitment) 10

Reproductive rate 0.13 (ratio of calves to adult females, modeled) 2

0.143 (ratio of calves to adult females) 2

0.114–0.117 (ratio of calves to whales) 2

0.104 (a model population of 1,000 that included 94 calves) 3

0.097 (ratio of calves to whales) 6

0.08–0.10 (ratio of calves to whales) 10

0.12 (ratio of calves to whales) 11

0.056–0.10 (ratio of calves to whales) 12

0.08–0.14 (ratio of calves to whales) 13

0.08 (unknown) 14

Lactation period At least 2 years 1

21 months on average (based on length of gestation (14 months) x 33 

lactating/22 pregnant whales) 

2

23 months (range:18–32 months, analysis of data collected by Seaman 

and Burns [1981])

6

Calving interval 3 years 1, 2c, 3d

>2 years (based on the assumption that females produce 10 calves within 

a 14–15 year active breeding period) 

6e

2–3 years 15

a Sampling occurred in June, a time when most Alaskan belugas are born. It is possible non–pregnant 8–9 GLGs belugas would have conceived 

before their 10–11 GLGs birth date. 

b Found differences in maximum age based on sampling technique. Life span of netted whales tended to be lower (40 GLGs at Whale Cove) than 

those selected and harpooned (50 GLGs at Churchill, 53 GLGs at Mackenzie Delta). Similar results were reported by Brodie (1971) for whales 

netted in Cumberland Sound (40 GLGs). 

c In 7 of the 29 pregnant females examined from Whale Cove, lactation was still occurring and for some analyses a 2 year calving cycle was 

assumed for 25% of the adult female population (p. 1084). Sergeant (1973) concluded “overlap of pregnancy and previous lactation is infrequent 

so that calving occurs about once in 3 years.”

d For some female belugas. This was a tentative conclusion based on high conception rates noted in some females between the ages of 12–13 

GLGs and 44–45 GLGs. 

e Braham (1984) based this assumption on data from Brodie (1971) and Sergeant (1973) that age at first pregnancy is 6 years (12 GLGs) and last 

pregnancy is about 21 years (42 GLGs) resulting in a 14–15 year breeding period, which would allow only 6 calves rather than the 10 calves 

predicted by the authors if a female’s reproductive cycle is 3 years. However, this calculation was based on 2 GLGs = 1 year, using 42–12 = a 30-

year breeding period and a 3-year reproductive cycle would produce 10 calves.

Sources: 1. Brodie (1971) [Canada] Cumberland Sound, Baffin Island, population, n = 124 animals (86% captured in nets which biased the 

sample toward females with newborns), Fig.3 appears to show 51 females in the sample. 2. Sergeant (1973) [Canada] Churchill and Whale Cove 

in western Hudson Bay, additional information from the Mackenzie Delta, Beaufort Sea and Kara/Barents seas, Russia. 3. Burns and Seaman 

(1986) [Northwest Alaska]; 4. Robeck et al. (2005) [captive belugas]; 5. Allen and Smith (1978) reviewed in 6. Braham (1984); 7. Ohsumi 

(1979); 8. Béland et al. (1992) [Canada] St. Lawrence population; 9. Lesage and Kingsley (1998) [Canada] St. Lawrence population; 10. Brodie 

et al. (1981) [Canada] Cumberland Sound, Baffin Island; 11. Ray et al. (1984); 12. Davis and Finley (1979) [eastern Arctic]; 13. Davis and Evans 

(1982) [eastern Beaufort Sea and Amundsen Gulf]; 14. Breton-Provencher (1981) [Poste-de-la-Baleine region]; 15. Suydam (2009) [eastern 

Chukchi Sea].
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-24

beluga population where annual calf production appears to be cyclical (R. Michaud, Group for 

Research and Education of Marine Mammals, unpub. data). Also, it was assumed, based on midJuly beluga calf sightings in Cook Inlet during aerial surveys in the 1970s, and May calving 

reported by Alaska Native hunters for the Susitna area, that most calves were born by August. 

However, during annual photo-identification studies (2005 to 2015), McGuire et al. (2016) 

reported observations of neonate belugas in upper Cook Inlet extending from July through midOctober. 

Based on gestation and timing of birthing, mating is believed to occur sometime between late 

winter and early spring; however, there is little documentation on the mating behavior of 

belugas. A reproductive study of belugas in captivity reported that all conception (n = 13) 

occurred from February to June, with 80.6% of the conceptions occurring from March to May 

(Robeck et al. 2005). Suydam (2009) stated it was unlikely the eastern Chukchi Sea belugas 

became pregnant after late June since they did not observe fetuses of a length indicative of an 

August or September birth date.

Survival data for CI belugas consist of annual summaries of beach-cast and floating carcasses 

reported to the NMFS AKR, and consequently represent a minimum estimate of mortality for the 

CI beluga. From 1999 to 2005, when the population size averaged approximately 350 animals

and a limited harvest of CI belugas occurred, an average of 12 mortalities were reported each 

year (Vos and Shelden 2005). This provided an estimated annual survival probability for CI 

belugas of 0.97 per year. From the literature, survival probabilities for belugas have been 

estimated as low as 0.84 per year but most were above 0.90 per year. The lactation period is 

known to last longer than one year, so calf survival closely relates to survival of the mother 

during the first year following birth. While survival rates and age at maturity have been 

estimated for males, these estimates did not significantly differ from those for females.

Data are not available for the CI beluga population to precisely determine the generation 

time, however, when we consider available information regarding the age at first reproduction 

and age at senescence for belugas, we estimate a generation time for belugas of approximately 25 

years.

9 The International Union for Conservation of Nature’s (IUCN) Red List of Threatened 

Species10 estimated the generation time for belugas in Cook Inlet to be 16 years based on the 

information provided by Burns and Seaman (1986), which considered a year to be represented by 

two GLGs, rather than the currently recognized one GLG/year. Thus, 16 years may 

underrepresent the actual generation time for belugas. The generation time of between 26 to 30 

years has been proposed for belugas in the St. Lawrence Estuary (David Lee, Committee on the 

Status of Wildlife in Canada [COSEWIC] Member, pers. comm. to R. Hobbs, AFSC MML,

October 2014). Therefore, we determine our estimate of generation time of 25 years to be 

reasonable.

 

9 Generation time was estimated by subtracting the age at first reproduction (~8–12 years) from the age at senescence (~40–43

years), multiplying by 1⁄2, and then adding the age at first reproduction. Given the imprecision of the data available, we 

determined 25 years is a reasonable estimate of generation time. 

10 The IUCN Red List of Threatened Species information webpage for Cook Inlet beluga whales was accessed October 17, 2014, 

and is available at: http://www.iucnredlist.org/details/full/61442/0.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-25

6. Hearing and Vocalizations 

a. Beluga Hearing

Several published studies (e.g., Awbrey et al. 1988; Klishin et al. 2000; Mooney et al. 2008) 

and one unpublished study (White et al. 1978) have assessed the hearing sensitivity of captive 

belugas using behavioral or electrophysiological (i.e., auditory evoked potential [AEP]) methods. 

In addition, one published study investigated hearing sensitivity (from 4 to 150 kilohertz11

[kHz]) in seven wild Bristol Bay belugas using AEPs (Castellote et al. 2014). Hearing abilities in 

these belugas were generally similar to those measured in captive belugas. All seven belugas

heard well, up to at least 128 kHz, and two heard up to 150 kHz. Lowest auditory thresholds 

(35–45 dB12) were identified in the range 45 to 80 kHz (Figure 12). Greatest differences in 

hearing abilities among individuals occurred at both the high end of the auditory range and at 

frequencies of maximum sensitivity. Collectively, these studies indicate belugas have an overall 

auditory bandwidth of approximately 40 Hz to 150 kHz, roughly eight times that of humans (Au 

1993).

Notes: Data are means ± SD for wild belugas (black circles). Audiograms from captive belugas are indicated by gray symbols. Lower thresholds 

(intensity of a signal heard by the beluga) indicate better hearing. Best hearing for the wild belugas was typically in the 22.5–80 kHz range, with 

the absolute lowest thresholds between 45 and 80 kHz.

Sources: Figure from Mooney and Castellote 2012; audiograms from White et al. 1978, Awbrey et al. 1988, Mooney et al. 2008, Klishin et al. 

2000, and Mooney and Castellote 2012.

Figure 12. Audiograms from wild belugas and captive belugas.

b. Beluga Echolocation

 

11 The hertz (symbol Hz) is the unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of 

its most common uses is the description of sound sine waves as the frequency of musical tones.

12 The decibel (dB) is a logarithmic unit that indicates the ratio of a physical quantity (in this case sound intensity) relative to a 

specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power 

quantities. For sound in water, the reference quantity is 1 microPascal. Sound Pressure Level (dB)

Frequency (kHz)
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-26

Beluga echolocation (sonar) has been well studied and described (Au et al. 1985, 1987). 

Studies show that belugas have highly developed and sophisticated echolocation capabilities,

with the capacity to adapt their click energy distribution as a function of the ambient noise in 

order to maximize the echo reception (Au et al. 1985). The echolocation capabilities of belugas, 

when compared to bottlenose dolphins, appear to be superior in the ability to detect targets (e.g., 

short steel cylinders) in the presence of masking noise (Turl et al. 1987) and in the ability to 

detect targets in clutter (reverberation composed of echoes scattered back to a sonar from objects 

and heterogeneity in the water and on its boundaries) (Turl et al. 1991). In an effort to detect a 

target in the midst of masking noise, belugas were shown to gain signal-to-noise ratio by 

projecting and receiving signals off the surface of the water, a technique not observed in the 

bottlenose dolphin (Penner et al. 1986). Hypothetically, this may be a similar strategy to using 

the underside of ice cover to reflect signals, possibly an adaptation to living in an Arctic 

environment. Turl and Penner (1989) suggest: “[T]he beluga lives in a high-noise and 

reverberant environment. It might be expected that the beluga’s sonar system has developed 

optimal adaptations to minimize the effects of interference found in the Arctic.” 

c. Beluga Acoustic Social Signals

Belugas are among the most vocal cetaceans, making a wide variety of sounds that fall into 

two acoustic categories: whistles or narrow band frequency modulated vocalizations, and pulsed

sounds or trains of broad band pulses. The latter can be divided into two functional categories: 

click trains, used largely for echolocation, and burst pulse sounds (bursts of pulses with rapid

pulse repetition rates), believed to be social signals, which may sound to the human ear like 

grunts, squawks, screams, whines, and whistles.

These varied sounds earned belugas the nickname “Sea Canaries” by early Arctic whalers. 

There have been a number of attempts to classify the vocal repertoire of belugas (Fish and 

Mowbray 1962; Morgan 1979; Sjare and Smith 1986a, 1986b; Faucher 1988; Bel'kovich and 

Sh'ekotov 1993; Recchia 1994; Angiel 1997; Belikov and Bel'kovich 2001, 2003, 2006, 2007, 

2008; Karlsen et al. 2002). This body of data provides some indication that sounds vary with 

behavioral and group context, and suggests geographic variation in signal use among 

populations. It is thought that these calls, both in captivity and in the wild, function to maintain 

group cohesion, and the variants shared by related animals are used for mother-calf recognition 

(Vergara et al. 2010). For example, belugas show an increase in the rate of vocalizations during 

social gatherings in the Canadian high Arctic, in Svalbard, Norway, and in the White Sea, Russia 

(Sjare and Smith 1986b’ Karlsen et al. 2002; Belikov and Bel’kovich 2003). They become much 

quieter when disturbed by humans or frightened (Finley 1990, Karlsen et al. 2002; Sjare and 

Smith 1986b; Belikov and Bel’kovich 2003). There is evidence of a decrease or even a cessation 

in acoustic activity of belugas in the presence of natural predators (e.g., killer whales) or engine 

noise.

Belikov and Bel’kovich (2003) attempted to correlate specific beluga call types with four 

behavioral states: quiet swimming, social interactions, sexual behavior, and disturbance caused 

by humans. While all call types were heard during all four behavioral states, there was a 

significant increase in “chirps” heard during sexual behavior and social interactions, and a 

decrease in whistles during sexual behavior. The conclusion was that “chirping” was the best 

acoustic indicator of beluga behaviors, marking both social and sexual interactions (Belikov and 

Bel’kovich 2003).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-27

d. Acoustics of CI Belugas

Limited work has been done regarding acoustics of CI belugas. Castellote et al. (2011) 

recorded the acoustic behavior of CI belugas concurrently with visual observations using both 

boat-based and land-based methods in open waters as well as inside river mouths (Eagle and 

Little Susitna Rivers). The authors described how the acoustic behavior of CI belugas is 

modified when feeding. During presumed feeding or prey search, social calls were absent and 

echolocation clicks often occurred in train packets. Burst pulses were also found more often, 

although the authors indicated that few of these were conclusively assigned as “terminal buzzes”

related to prey capture since most of the events were partially incomplete, probably due to the 

highly directional nature of these sounds. The authors concluded that echolocation train packets 

ending with a terminal buzz were produced by feeding belugas, that this behavior was commonly 

recorded in river mouths, and that it could be acoustically monitored with the potential to be used 

as an indirect indicator of foraging behavior. Garner et al. (2014) also used echolocation data to 

assess the seasonal use of Eagle River by CI belugas.

As noted above (see Section II.B.4. Use of Critical Habitat by Belugas), Castellote et al. 

(2016a) obtained information on the seasonal distribution and foraging behavior of belugas in 

Cook Inlet through passive acoustic monitoring of beluga social calls and echolocation activity at 

13 locations in lower Cook Inlet and upper Cook Inlet. Belugas were detected at 12 of the 13 

locations, with no detections in lower Cook Inlet at Homer Spit (the most southern site

monitored). In general, the seasonal distribution of acoustic detections was consistent with 

descriptions based on aerial surveys and satellite telemetry. Echolocation data were also used to 

explore when and where presumed foraging buzzes occurred.

Passive acoustic recordings of CI belugas have also been collected in conjunction with a 

construction project at the Port of Anchorage. Širović and Kendall (2009) deployed a passive 

acoustic array of sonobuoys during 20 days in summer 2009 to acoustically detect the presence 

of belugas in the vicinity of in-water pile driving at the Port of Anchorage. Belugas were 

detected 55% of the monitoring time, with virtually all detection based on echolocation clicks 

(one whistle and over 65,000 clicks). Kendall et al. (2013) suggested that during the monitoring 

period, other lower frequency beluga whale vocalizations (e.g., whistles) were potentially 

masked, there may be have been an overall reduction in beluga vocalizations, or it is possible 

belugas were avoiding the area during construction activity.

A review of available information reveals four main gaps regarding our acoustic knowledge on 

CI belugas:

1. Hearing sensitivity data collected for seven wild belugas indicated that hearing abilities in 

these belugas were generally similar to those reported for captive belugas (Castellote et 

al. 2014). Thus based on this one study, it appears that hearing measurements in a 

laboratory setting may be reasonable substitutes for data from wild belugas. However, 

larger sample sizes are needed to fully assess maximum hearing sensitivity and variability 

within the species (especially age and sex based differences).

2. Very specific noise types (e.g., simulated underwater explosions, pure tones, seismic water 

gun, white noise, icebreaker noises) have been used in hearing experiments with belugas. 

Even if these studies set the baseline information on the effect of noise in the beluga 

auditory system, their results might not be applicable to CI belugas because most of the 

noise sources tested are foreign to Cook Inlet. Castellote et al. (2016b) evaluated the 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-28

sources, acoustic characteristics, and frequency of occurrence of anthropogenic noise in 

Cook Inlet and concluded that the temporal prevalence and levels of anthropogenic noise 

measured “indicate that beluga communication and hearing is largely masked by 

anthropogenic noise in most of the locations and periods sampled.” Future research should 

broaden the geographic extent and months sampled, and improve the classification of 

unknown noise sources.

3. Little is currently known regarding chronic effects of noise exposure on belugas. CI 

belugas are exposed to anthropogenic noise sources of notable prevalence (e.g., tug boats, 

pile driving, dredging), but most of the studies to date have been focused on short-term 

and acute exposure to noise. Similarly, most of the current studies on the effects of 

anthropogenic noise on belugas have been focused at the physiological level (e.g., masked 

temporary threshold shifts, TTS, PTS), but the effects of anthropogenic noise at the 

behavioral level (e.g., geographical displacements, changes in acoustic communication) 

have barely been considered.

4. The current understanding of social communication in different populations of belugas 

highlights an important lack of standardized methods. Considering that the repertoire of 

beluga vocalizations has been suggested to vary geographically, the standardization of 

acoustic analysis methods is needed to better understand the population structure and 

seasonal distribution of this species. Research efforts in this direction will probably be 

beneficial in a broader scale, not just towards the Cook Inlet population.

7. Other Senses

Belugas have acute vision both in and out of the water. A beluga's eye is particularly well 

adapted for seeing in water. In air, certain features of the lens and cornea correct for the 

nearsightedness that result from the refraction (bending) of light rays as they go from water to 

air. A beluga’s retinas contain both rod and cone cells, indicating that they may have the ability 

to see in both dim and bright light (rod cells respond to lower light levels than do cone cells). As 

with other whales, belugas lack short wavelength sensitive visual pigments in their cone cells 

indicating a more limited capacity for color vision than most land mammals (Peichl et al. 2001; 

Levenson and Dizon 2003).

Among marine mammals, adaptation to a strictly marine environment has favored a primary 

sensory modality based on sound production and reception (Wood 1973). Other senses, such as 

smell, are diminished or even absent (Caldwell and Caldwell 1972). The available sensory 

channels that are utilized by marine mammals are acoustic, tactual, visual, and chemical 

(gustatory; Caldwell and Caldwell 1977; Winn and Schneider 1977). Except for the bottlenose 

dolphin (Herman 1980) and California sea lion (Thomas et al. 1992), few studies have examined 

in any detail the sensory capabilities of marine mammals. Olfactory lobes of the brain are absent 

in all odontocetes, suggesting that they have no sense of smell, although these lobes are found in 

the embryos (Kellogg, 1958). 

Some studies have noted sensory areas in beluga mouths that may function in taste (Haley 

1986). There is further evidence of chemoreception in the mouth in some species including the 

beluga. Reports have suggested that belugas react to blood in the water by quickly retreating and 

showing unusual alarm. Furthermore, it has been proposed that belugas release a pheromone 

when alarmed (Dudzinski et al. 2002).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-29

8. Social Organization 

Throughout their distribution, belugas are extremely social animals that typically migrate, 

hunt, and interact together, often in dense groups. In areas of the Arctic, belugas aggregate in the 

hundreds and sometimes thousands (O’Corry-Crowe 2002). High group cohesion and large 

group sizes may provide benefits to group members in terms of information gathering and 

transfer with regard to resource availability (e.g., prey, calving sites, oceanographic conditions) 

and cooperation in predator avoidance and reduced predation risk (Hamilton 1971; Reluga and 

Viscido 2005). It is not known whether social structure plays a role in determining which adults 

are available for breeding. It is thought that the basic social units of these groups are maternal 

lineages of adult females and their offspring and that males migrate separately (Smith et al. 

1994). Genetic evidence for Canadian stocks of belugas indicates that migration routes and 

summer distribution are maintained by maternal lineages (Turgeon et al. 2012); however, this 

information is unavailable for Cook Inlet. It is possible the strong site fidelity belugas exhibit 

may be learned during the period of dependence when the mother teaches the weaning calf to 

forage. 

In Cook Inlet, groups of four to 250 belugas have been observed during the ice-free months, 

and single whales are only occasionally seen (McGuire and Bourdon 2012; T. McGuire, LGL, 

pers. comm.). It is not known if groups represent distinct social divisions. Preliminary results 

from photo-identification research indicate beluga groups in upper Cook Inlet during the ice-free 

months of the field season are mixed and homogenous, without evident long-term sub groupings 

(McGuire et al. 2011). That is, there do not appear to be distinct groups consisting of CI belugas 

of the same gender or ages, and the available information suggest individual belugas spend time 

with different groups of belugas, many of which are found in all or several of the regions 

surveyed by the photo-identification project. Information on beluga social structure during 

months with ice and for groups found in the lower Inlet does not currently exist. Studies of 

beluga groups in the Kenai River and its vicinity were conducted 2011–2013 and indicate these 

are the same individuals that use the upper Inlet, with the same fluid social structure (McGuire et 

al. 2014a). 

9. Swimming and Diving Behavior 

Belugas typically swim between 1 and 10 kilometer per hour (km/hr) (0.6–6.2 miles per hour 

[mi/hr]), but have been estimated to sustain speeds over 20 km/hr (12.4 mi/hr) for periods of a 

half hour (Richard et al. 1998). Suydam (2009) estimated typical speeds at 2.5–3.3 km/hr (1.5–

2.0 mi/hr), and Smith and Martin (1994) estimated swimming speeds of 1.6–6.0 km/hr (1.0–3.7 

mi/hr) during the fall migration. 

According to Goetz et al. (2012a), CI belugas tagged from 1999–2000 displayed a mean 

transit rate of 2.8 (SD ±2.4) km/hr (1.7 mi/hr), with individuals’ travel rates ranging from 1.6 

(SD ± 2.0) km/hr to 4.3 (SD± 3.1) km /hr (1.0–2.7 mi/hr). Tagged CI belugas travelled faster 

during December to May than June to November, and travelled slower in coastal areas than they 

did in offshore waters of the Inlet (Goetz et al. 2012a). Based on an acoustic study conducted in 

Eagle River, swimming speeds of CI belugas were estimated to be from 1.8–7.56 km/hr (1.1–4.7 

mi/hr) (Castellote et al. 2013).

Belugas from stocks found in regions with access to deep water are capable of dives deeper 

than 1,000 m (3,281 ft) (Citta et al. 2013) and at vertical speeds of 2–7 km/hr (1.2–4.3 mi/hr; 

Heide-Jørgensen et al. 1998). In the areas of Cook Inlet occupied by belugas, the depth does not 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-30

exceed 100 m and much of the time the belugas are in waters less than 20 m (65.6 ft) depth. 

Consequently, CI belugas are able to access the entire water column. Typical dive sequences 

consist of three to five short intervals of 7–10 seconds followed by a longer dive of a minute or 

more. Mean dive depth ranged from 1.6 (SD ± 2.1) to 6.7 (SD ±10.4) m (5.2 to 22 ft) and mean 

dive duration ranged from 1.1 (SD ±1.3) to 6.9 (SD ±9.5) minutes (Goetz et al. 2012a), with 

shorter dives occurring in nearshore areas. The average dive interval (the time from the 

beginning of one surfacing to the beginning of the next) is 24.1 seconds for CI beluga (Lerczak 

et al. 2000). 

10. Foraging Behavior, Diet, and Fisheries Management

a. Foraging Behavior

Belugas are known to feed on prey that concentrate, including shrimp and schooling or 

spawning fish (Seaman et al. 1982), and beluga presence has been used by fish harvesters as 

indicators of fish abundance. Feeding both independently and cooperatively, belugas capture and 

swallow their prey whole, using blunt teeth to grab prey. Quakenbush et al. (2015) noted that 

because belugas swallow their prey whole, the diet of smaller (young) belugas is limited by the 

size of the esophagus to smaller prey. The suitability of some adult salmon as prey for young 

belugas may thus be limited, even when salmon are available. While belugas are known to eat 

large amounts of fish in spring and summer, little is known about winter distribution and less 

about winter feeding. An extensive review of potential CI beluga prey species, including their 

distribution and known abundances, is presented in Appendix IX.F – CI Beluga Prey 

Supplement.

Current data on the foraging ecology of CI belugas are quite limited and based primarily on 

visual observations of whales in areas of seasonal prey concentrations. However, dive behavior

data was obtained through satellite tags deployed on 11 belugas during 1999 to 2002 (Goetz et 

al. 2012a). Dives were significantly shorter and shallower June to November versus December to 

May. Over 50% of the dive effort occurred in shallow, nearshore areas of Chickaloon Bay, 

Susitna Delta, Knik Arm, Turnagain Arm, and Trading Bay, a behavior suggesting feeding in 

these areas. These locations are also recognized as areas where anadromous prey concentrate 

when entering river mouths. Belugas in northern Cook Inlet likely benefit from the tendency of 

anadromous prey species to be concentrated by shallow water and the time required to transition 

from salt water to fresh as these prey enter the stream mouths, which presumably makes them

easier to capture.

Belugas in Cook Inlet appear to feed extensively on concentrations of spawning eulachon in 

the spring; CI belugas then shift to foraging on salmon species as eulachon runs diminish and 

salmon return to spawning streams. While winter foraging is not well known, some components 

of beluga whale populations in other areas forage more on benthic species (DFO 2011). It is 

presumed that CI belugas in winter forage more on benthic species or opportunistically on 

infrequently encountered pelagic species. Analysis of CI beluga stomach contents indicated

gadid and flounder species were relatively important prey items in spring and fall (and likely 

winter), seasons when fewer salmon are available (Quakenbush et al. 2015). The degree of prey 

switching, either seasonally or on longer time scales, is not well understood, although belugas

must be somewhat opportunistic with respect to foraging selectivity relative to prey availability.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-31

b. Diet

The diet of belugas throughout their circumpolar range is dominated by fish and invertebrate 

prey. While published reports on beluga diets are available from Canada (Vladykov 1946, cited 

by Seaman et al. 1982; Doan and Douglas 1953, cited by Seaman et al. 1982; Sergeant 1973), 

Russia (Kleinenberg et al. 1969, cited by Seaman et al. 1982; Tomlin 1967, cited by Seaman et 

al. 1982), and Europe (Lono and Oynes 1961, cited by Seaman et al. 1982), published data for 

Alaska are limited to one published report (Seaman et al. 1982; n = 119 belugas from three 

stocks) and several unpublished reports from Bristol Bay (Brooks 1954, 1955, 1956, 1957; 

Lensink 1961, cited by Seaman et al. 1982; Klinkhart 1966, cited by Seaman et al. 1982). Diet 

data for CI belugas are currently limited to a relatively small sample of stomach contents 

(Quakenbush et al. 2015), stable isotope analyses (Nelson and Quakenbush 2014), as well as 

observations from Alaska Native subsistence hunters (Fall et al. 1984; Huntington 2000).

A total of 53 stomachs from CI belugas were collected from 1992 to 2010 (Quakenbush et al. 

2015). Stomachs collected from 1992 to 2001 (April to October; n = 24) were analyzed 

separately from stomachs collected during 2002 to 2010 (March to November; n = 27). Thirty

five non-empty stomachs were sampled; 17 from the earlier and 18 from the later time periods. 

For 1992 to 2001, the only prey items identified were eulachon and Chinook (king) salmon, with 

additional items identified only as “salmon.” However, because only a portion of the contents 

from each stomach collected was analyzed, additional prey items were likely present. For nonempty stomachs from 2002 to 2010, fish were identified in 18 stomachs and invertebrates in nine 

(Table 2). Fish prey included seven families and at least 12 species. Fish frequencies of 

occurrence were greatest for salmon (67%), gadids (39%), smelts (11%), and flounders (11%); 

salmon frequencies included coho (28%), Chinook (11%), and chum (17%). Gadid frequencies 

included saffron cod (22%), walleye pollock (17%), and Pacific cod (6%). Eulachon was the 

only smelt identified, whereas two flounder species, yellowfin sole (11%) and starry flounder 

(6%), were identified. A longnose sucker was the only freshwater fish found. Seven types of 

invertebrates were found in the beluga stomachs, with the frequency of occurrence among nonempty stomachs being highest for shrimp (33%), followed by polychaetes (11%) and amphipods 

(11%). Other invertebrates included Tanner crab (6%) and sponges (6%). Because fish appearing 

in beluga stomachs have also consumed a variety of prey, including polychaetes, shrimps, 

amphipods, and other fishes (Clausen 1981, 1983; Seaman et al. 1982), some prey items in the 

beluga stomachs could have resulted from secondary ingestion.

Alaska Natives have reported CI belugas feeding on freshwater/brackish fish, including trout, 

whitefish, northern pike, grayling, and Pacific tomcod (Fall et al. 1984; Huntington 2000).

Stomach samples from CI belugas are lacking for the winter months of December to 

February. Dive data from belugas tagged with satellite transmitters suggest whales feed in deeper 

waters south of the Forelands during winter (Hobbs et al. 2005), possibly on prey such as 

flatfishes, sculpins, and gadids. Diet data for early spring are limited to one dead whale found in 

March 2003, which had thinner blubber than beach-cast belugas found in summer. This early 

spring beluga stomach contained saffron cod, walleye pollock, Pacific cod, eulachon, Tanner 

crab, shrimp, and polychaetes (NMFS unpub. data; Table 2).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-32

Table 2. Prey items from CI beluga stomachs, 2002 to 2010.

No. stomachs

Mar Jun Jul Aug Sep Oct Nov

Total

among

months

Percent

frequencya

Total no. stomachs 1 3 4 7 3 8 1 27

Total no. stomachs with prey 1 2 4 5 1 5 0 18 67

Stomachs that contained fish 1 2 3 5 1 5 0 17 94

Salmon 0 2 3 4 1 2 0 12 67

Gadid 1 0 0 1 1 4 0 7 39

Eulachon 1 0 1 0 0 0 0 2 11

Flounder 0 0 0 1 0 1 0 2 11

Other identified fish 0 0 0 2 0 1 0 3 17

Unidentified fish 1 0 0 1 0 0 0 2 11

Stomachs that contained invertebrates 1 0 3 1 0 4 0 9 50

Shrimp 1 0 1 1 0 4 0 7 39

Amphipod 0 0 1 0 0 1 0 2 11

Polychaete 1 0 0 0 0 1 0 2 11

Other identified invertebrates 1 0 2 1 0 0 0 4 22

Unidentified invertebrates 0 0 0 0 0 1 0 1 6

a Percent frequency is the number of stomachs containing a prey item relative to the total number of non-empty stomachs.

Source: L. Quakenbush, ADF&G, unpub. data.

Analysis of stable carbon (δ13C) and nitrogen (δ15N) isotopes in 23 archived skull bones 

revealed a depletion of both δ13C and δ15N values between 1964 and 2007 (Nelson and 

Quakenbush 2014). Annual growth layers from teeth (1961–2007) also showed a decline in 

isotope values (Nelson and Quakenbush 2014). However, the decline in δ13C appeared steady

over time, while the decline in δ15N was steep from 1970 to 1978 and more gradual after 1978. 

The authors noted that the decline in δ13C is consistent with the reduction of the CI belugas’

range into the upper more freshwater reaches of Cook Inlet, where their prey may have a greater 

freshwater influence and thus be more depleted in δ13C than the same prey from marine waters. 

The overall decline in δ15N indicates a decline in trophic level. Prey isotope signatures were not 

identified to species. However, possible examples of such a change to lower trophic level prey 

include a switch from pollock or Pacific herring to capelin or sandlance, or a switch from older 

piscivorous pollock to younger planktivorous pollock.

Caution is warranted regarding interpretation of diet information. For example, more-recently 

ingested prey items are likely to be more identifiable owing to less digestion, although hard parts

of prey may accumulate in the digestive tract. However, recently eaten prey are also more likely 

to be regurgitated from stimuli such as stress. The cause of mortality may create additional bias, 

as stranded belugas may have fed differently, due to poor health, compared to harvested belugas. 

Thus, depending on beluga health, prey type, and time since consumption, some prey items may 

be over or under-represented in diet analysis from stomach samples. The relatively small sample 

size for CI beluga stomachs remains a concern as aspects such as feeding preferences by 

individual whales may be underrepresented in the current analysis. While salmon is obviously 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan B. Natural History of CI Belugas

II-33

important as a prey item throughout the spring to fall season, some whales may be more 

proficient at foraging on salmon, while other whales supplement salmon with other prey items. 

Thus, a better understanding of foraging selectivity by individual whales is compromised by the 

low sample size.

c. Fisheries Management

Management of salmon fisheries in Alaska attempts to constrain harvests to be no greater 

than the level of surplus production, defined as returning adult salmon in excess of the spawning 

production that is needed to maintain productive salmon populations (Quinn and Deriso 1999). 

In addition to reproductive needs, harvest considerations must include commercial fisheries and 

upstream consumptive uses such as recreational, personal use, and subsistence fisheries (Shields 

2010), as well as allowances for natural mortality, which includes predation by belugas, bears, 

and other species. However, it is unlikely that escapement goals will be met in all tributaries 

across all years. Thus, while fishery management, on average, should maintain sufficient total 

numbers of prey for belugas, the timing of prey concentration or densities in the river mouths can 

vary and may not always be adequate for efficient feeding by belugas.

An important concern is that salmon are an essential feature of CI beluga critical habitat (76 

FR 20180; 50 CFR part 226.220), and some species of salmon, most notably Chinook salmon,

have had reductions in run strength in Cook Inlet and throughout Alaska. In 2012, the U.S. 

Secretary of Commerce determined in response to a request from the Alaska governor that 

commercial fishery failures due to fishery resource disasters had occurred for Chinook salmon 

stocks in the Yukon, Kuskokwim, and Cook Inlet regions.

13 The declaration acknowledged 

hardships for commercial, sport, and subsistence users as a result of the Chinook fishery failures. 

To identify key knowledge gaps and discuss how best to address those gaps, ADF&G sponsored 

a Chinook salmon symposium, “Understanding the Abundance and Productivity Trends of 

Chinook Salmon in Alaska,” in Anchorage during October 22–23, 2012.

14 Subsequently, 

ADF&G worked collaboratively with federal agencies and academic partners to develop a stock 

assessment and research plan with recommended studies to address critical knowledge gaps 

(ADF&G Salmon Research Team 2013). Implementation of strict fishery management actions 

has been necessary to meet escapement objectives, and many fisheries have been curtailed to 

protect Chinook salmon. In 2016, runs improved for the westward stocks (i.e., Yukon, 

Kuskokwim, and Nushagak), as well as in Kodiak and Cook Inlet, but overall these runs were

still below long-term averages. Runs in these regions are expected to continue to improve.15

More information on this topic is presented in Appendix IX.F – CI Beluga Prey Supplement.

 

13 See news release at: http://www.nmfs.noaa.gov/stories/2012/09/09_13_12disaster_determinations.html; A copy of the letter 

from Acting Secretary Blank to Governor Parnell can be viewed at: 

http://www.nmfs.noaa.gov/stories/2012/09/docs/blank_parnell_9_13_12.pdf.

14 For more information about the Chinook salmon symposium, visit ADF&G’s website at: 

http://www.adfg.alaska.gov/index.cfm?adfg=chinook_efforts_symposium.information.

15 Information on Chinook salmon runs in 2016 is from ADF&G’s website (accessed December 2016) at: 

http://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan C. CI Beluga Population Size and Trends

II-34

C. CI Beluga Population Size and Trends

1. Historic Abundance Estimate and Carrying Capacity

Aerial surveys in the 1960s, 1970s, and early 1980s counted belugas in Cook Inlet but only a 

few of these had sufficient coverage to estimate the population size (Calkins 1984, 1989). A 

survey in 1979 resulted in an estimate of 1,293 whales using a correction factor of 2.7 developed 

to account for submerged whales under similar conditions in Bristol Bay (Calkins 1989). This is 

the best available estimate of historical beluga abundance in Cook Inlet, and represents the 

maximum observed size of this population. Therefore, based on the best information available, 

NMFS has adopted this maximum historical abundance estimate, rounded to 1,300 belugas, as 

the estimated carrying capacity to be used for management purposes (65 FR 34590, May 31, 

2000). We have no data at this time to indicate whether this carrying capacity may have changed.

Between 1979 and 1994, the CI beluga population declined from 1,300 to 650 belugas, which 

represents an average annual decline of around 5% (i.e., 650 = 1300*0.955(1994-1979)). While the 

decline between 1994 and 1998 is well documented and attributed to unsustainable subsistence 

harvest, empirical data are lacking for the period between 1979 and 1994 to identify a 

mechanism of decline. Native subsistence harvest (enumerated through hunter interviews) was 

significant during the 1970s and 1980s and may have been at levels similar to the hunts reported 

in the mid-1990s, but there was no comprehensive count of subsistence harvest until the 1990s 

(Mahoney and Shelden 2000). Commercial and sport hunts also occurred during the 1960s and 

1970s, but no information is available to assess whether the 1979 abundance estimate of 1,293 

(based on the 1979 ADF&G survey; Calkins 1989) may represent a partially depleted population, 

and thus a conservative estimate of Cook Inlet carrying capacity for belugas.

2. Recent Abundance Estimates and Population Trends

NMFS began conducting comprehensive, systematic annual aerial surveys of the beluga

population in Cook Inlet in 1993 (Hobbs et al. 2015b). Beginning with the 2012 annual survey, 

the survey schedule was switched from annually to biennially, to occur in even numbered years

(see Hobbs 2013). These surveys occur in early June (except in 1995 when the survey was in late 

July), include the upper, middle, and lower sections of the Inlet, and are stratified to focus survey 

effort in the areas of the upper Inlet where belugas are typically at their highest concentrations 

during June. At the time of publication of this document, aerial surveys had been flown in 2016;

however, the data analysis to determine the 2016 abundance estimate had not been completed.

Annual estimates of the numbers of CI belugas resulting from these surveys documented a 

decline in abundance of nearly 50% between 1994 and 1998, from an estimate of 653 whales to 

347 whales (Table 3). This period of rapid decline was associated with a substantial, unregulated 

subsistence hunt; although the hunt was regulated starting in 1998, CI beluga numbers did not 

increase. An analysis indicated the decline in beluga abundance from 1994 to 1998 was 

adequately explained by the estimated take from the subsistence hunt. With the very limited hunt 

beginning in 1999 (a total of five whales hunted from 1999–2014, 16 years) NMFS anticipated 

that the population would begin to increase at a growth rate of between 2% and 6% per year. The

2014 abundance estimate was 340 belugas, with a declining trend for both the most recent 10-

year time period (–0.4% per year; standard error [SE] = 1.3%) and since the hunt was managed 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan C. CI Beluga Population Size and Trends

II-35

Table 3. CI beluga abundance estimates and coefficients of variance (CVs), June/July 1994 to 2014.

Yeara Survey dates Abundance estimate CVb

1994 June 1–5 653 0.24

1995 July 18–24 491 0.21

1996 June 11–17 594 0.20

1997 June 8–10 440 0.13

1998 June 9–15 347 0.17

1999 June 8–14 367 0.09

2000 June 6–13 435 0.14

2001 June 5–12 386 0.10

2002 June 4–11 313 0.10

2003 June 3–12 357 0.08

2004 June 2–9 366 0.13

2005 May 31–June 9 278 0.10

2006 June 5–15 305 0.10

2007 June 7–15 375 0.08

2008 June 3–12 375 0.11

2009 June 2–9 321 0.11

2010 June 1–9 340 0.08

2011 May 31–June 9 284 0.09

2012 May 29–June 7 312 0.13

2014 June 3–12 340 0.08

a Surveys in 1993 were not suitable for analysis using the abundance estimation methods of 1994 and later. No surveys were conducted in 2013 or 

2015.

b CV estimates prior to 2011 used the method of Hobbs et al. (2000) in previous publications. These have been recalculated using a revised CV 

formula based on the standard error of the daily abundance estimates and an estimate of the variance in behavior of the whales which better 

reflects the sources of variability in the estimate. The method for calculating the CVs was revised in 2011; CV’s for older estimates have been 

recalculated using the new formula.

Source: Shelden et al. 2015a; Hobbs et al. 2015b.

in 1999 (–1.3% per year, SE = 0.7%) (Shelden et al. 2015a; Figure 13). Thus, the population is 

not growing as expected despite the regulation of the subsistence harvest.

3. Small Population Dynamics

Small populations, such as the CI beluga population, may face inherent risks that large 

populations do not, simply as a result of their small population size. Small population dynamics 

may be at play when the impact to individual survival and fecundity increases as the population 

abundance decreases, or when there are persistent effects that result from a population having 

been small at an earlier time. These small population dynamics may manifest in various ways, 

including inbreeding, loss of genetic or behavioral diversity, or Allee effects. The Allee effect 

refers to a positive relationship between individual fitness and either abundance or densities of 

individuals (Stephens et al. 1999). For example, a very small population may experience Allee 

effects such as reduced reproductive success due to difficulties finding mates or reduced foraging 

success due to difficulties in locating prey. Reduced population sizes could mean reduced 

breeding opportunities and an increased potential for breeding with relatives. If a population 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan C. CI Beluga Population Size and Trends

II-36

Notes: Abundance estimates for belugas in Cook Inlet with 95% confidence intervals for revised coefficients of variation (CVs) (vertical bars). 

From 1994 to 1998, when the harvest was unrestricted, the annual rate of decline was –13.7% (SE = 0.045) per year. In the years since a hunting 

quota was in place (1999–2014), the rate of decline was –1.3% (SE = 0.7%) per year. The 10-year trend (2004–2014) was –0.4% (SE = 1.3%) per 

year. 

Source: Shelden et al. 2015a.

Figure 13. Estimated abundance of CI belugas, 1994–2014, with 95% confidence intervals for each estimate

(vertical bars).

remains small, genetic diversity will decrease with each generation, resulting in a greater risk of 

extinction. Even if the population later increases in size, there may still be lingering 

consequences of the low genetic diversity. Reduced genetic diversity could result in:

• Increased susceptibility to disease due to reduced variety of immune responses within 

inbred individuals, such that each beluga is more susceptible to a disease organism and 

also more likely to suffer severe symptoms.

• Increased risk of epidemic disease due to loss of variability among individuals. With 

more similarity among individuals, the disease organism also requires less adaptation 

among individuals, resulting in greater virulence and more rapid spread.

• Decreased resilience to environmental change at both individual and population levels. 

Individual belugas will have a more limited phenotypic (i.e., the observable properties of 

an organism that are produced by the interaction of the genotype and the environment)

response to changes in the environment; this limited response will narrow the adaptive 

range for the population.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan C. CI Beluga Population Size and Trends

II-37

• Decreased fecundity due to failed pregnancies and birth defects. With loss of diversity in 

the population, the likelihood increases for a fetus to develop a phenotype with decreased 

survival, resulting in a lost reproductive opportunity and reducing the net number of 

offspring that a female produces over her lifetime.

While these are potential consequences of small population size, NMFS concluded that the 

Allee effect is not a relevant concern for CI belugas unless the population size is smaller than 50 

animals (Hobbs et al. 2006). Similarly, inbreeding depression and loss of genetic diversity do not 

pose a significant risk to CI belugas unless the population is reduced to fewer than 200 whales 

(Hobbs et al. 2006).

Little is known about the social structure of CI belugas and how it relates to effective 

population size. Social structure may limit who and how many belugas breed, resulting in a 

lower effective population size and reproductive capacity than the population size and age-sex 

composition would indicate. In addition, some behaviors are transmitted from parents to 

offspring in other better-studied matriarchal odontocetes. In these other matriarchal odontocete 

groups, behavioral variation of females is passed to their offspring, much like genetic variation

(e.g., Würsig and Pearson 2015). As a result, social units or groups within the same population 

might display significant behavioral differences. Seasonal foraging strategies and site fidelity are 

examples of learned behaviors. Belugas show strong site fidelity, which may be learned during 

the period of dependence when the mothers teach the weaning calves to forage. Loss of 

behavioral diversity could result in:

• Reduced spatial distribution, increased risk of stranding, reduced prey choices, and 

reduced predatory efficiency due to fewer learning opportunities and greater similarity of 

experiences among remaining females.

• Decreased juvenile survival due to a reduction of learned recognition of habitat and 

resources, such as alternative prey, refuge from predators or disturbance, or other usespecific areas (Wade et al. 2012).

• Reduced socialization with fewer opportunities to learn foraging techniques, mating, 

group cohesion, and hierarchical definition or strengthening, as well as a reduction in 

mutual defense against, or avoidance of, predators. A decline in the population will be 

paralleled by a reduction in behavioral diversity. 

• Overall fitness and resilience to perturbations such as catastrophic events. 

CI belugas have exhibited a marked contraction of their summer habitat range. If CI belugas 

are matriarchal and pass knowledge from female to offspring, it is possible that some knowledge 

regarding preferred summer habitats in mid- and lower-Inlet might not have been passed on to 

the current generation. If this is the case, it is unknown how long it would take for these habitats

to be recognized again by individuals in the current or a recovered CI beluga population. Our 

knowledge regarding CI beluga social structure and differences in behavior among groups is 

quite limited, but the available information indicate that large groups of CI belugas observed in 

the Susitna River Delta do not appear to be segregated by color or age-class, with most groups 

consisting of both white and gray animals (McGuire et al. 2014b). Photo-identification studies of 

the upper CI also suggest that most, and perhaps all, of the CI beluga population uses Eagle Bay 

seasonally, with 90% of CI belugas also having been seen elsewhere in upper CI (McGuire et al. 

2014c). Thus there seems to be significant intermixing of age groups/color classes and a high 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan C. CI Beluga Population Size and Trends

II-38

resight rate of individuals in multiple locations, and at this time we have no information to 

suggest there has been a loss of behavioral diversity in the CI beluga population.

Although reduction of range likely increases the risk of extinction, the implications of this 

shift are not entirely clear and are in need of investigation. Range contractions generally increase 

vulnerability to catastrophic loss from stochastic events and point sources of disturbance, 

disease, and mortality. These risks may have become exacerbated in the CI beluga population by 

a range contraction to the area of greatest human impact. It is not known how the range 

contraction may have altered behavior and habitat use within the consistently occupied areas in 

the upper Inlet. With fewer whales, prey may be relatively more abundant, thus reducing 

competition and the need for more wide ranging movements. Concentrating in large numbers in 

discrete areas appears to be a basic trait of belugas and a strategy by the Cook Inlet population. 

While likely increasing vulnerability to catastrophic events, such behavior may reduce risk from 

other factors such as predation. It is essential to focus research on understanding both the cause 

and implications of the range contraction in CI belugas.

4. CI Beluga Population Viability Analysis (PVA) 

A population viability analysis (PVA) for CI belugas that was completed at the time of listing 

under the ESA indicated a risk of extinction in 100 years between 1% and 27% (Hobbs and 

Shelden 2008). The model that NMFS considered to best represent the risk to the CI beluga 

population indicated a 26% probability of extinction in 100 years. The detailed PVA population 

model used the abundance estimates for 1994 to 2008 and accounted for immature and mature 

stages of both sexes (Hobbs and Shelden 2008). The PVA was based on a Bayesian analysis16

using a population model that accounts for the removals from the population by the subsistence

hunt, births and deaths in the population, and time lags in the response of the population to 

changes. More recently, Hobbs et al. (2015c) developed another PVA analysis that incorporated 

five additional abundance estimates (for the years 2010, 2011, 2012, and 2014). This recent PVA 

included some model scenarios that were not included in the 2008 analysis, and the values for 

some model parameters differed from those used in corresponding models in Hobbs and Shelden 

(2008). There was considerable variation in risk of extinction at 100 years among the models, 

with the probability of extinction (among the five models that best fit the existing CI beluga data, 

along with the model accounting for risk of catastrophic events) ranging between 0% and 14%.

Based on the modelling results, the authors concluded it is likely the CI beluga population will 

continue to decline or go extinct unless factors determining its growth and survival are 

ameliorated.

 

16 Statistical modeling technique that factors in uncertainty.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-39

D. Sources of CI Beluga Mortality or Injury

1. Natural Sources

a. Predation 

The only known current predator of CI belugas is the “transient” or mammal-eating killer 

whale; there has not been a subsistence hunt by Alaska Natives in Cook Inlet after 2005.

However, it is possible that sharks may also occasionally prey upon belugas.

Killer whales are infrequently reported (Table 4) in upper Cook Inlet (Shelden et al. 2003; 

NMFS, unpub. data), which is now the primary summer range of CI belugas (Rugh et al. 2010). 

The contraction in CI beluga summer range to the shallow waters of the upper Inlet may reduce 

the opportunity for killer whales to pursue belugas in this area.

Interviews with people that have fished the upper Inlet for 20 to 50 years reported few 

sightings of killer whales (Shelden et al. 2003). In his study of TEK, Huntington (2000) 

interviewed Alaska Native beluga hunters who reported that killer whales were rarely seen in the 

upper Inlet or near belugas. Currently, beluga sighting networks are scattered along those 

portions of Cook Inlet shorelines that are road-accessible, and interest among the public is high, 

so there is an increased opportunity for any killer whale occurrences near Cook Inlet road access 

points to be reported, especially when these include encounters with belugas. 

Additional evidence that killer whale presence in upper Cook Inlet is rare comes from beluga 

observational and photo-identification work. Between 2004 and 2014, over 30,800 observational 

hours were logged between May and October in areas that included Turnagain Arm, western 

upper Cook Inlet, the area west of Fire Island to the Little Susitna, Knik Arm, and around the 

Kenai River, and no killer whales were observed (McGuire, LGL, unpub. data).

Killer whales have been seen in the upper Cook Inlet in Turnagain Arm and Knik Arm, 

between Fire Island and Tyonek, and near rivers along the Susitna Delta (Shelden et al. 2003; 

NMFS, unpub. data). Killer whales have also been reported in areas of the mid and lower Inlet, 

including near the Chuitna and Kenai Rivers (Table 4) and Kamishak Bay. In addition, Lammers

et al. (2013) reported a single detection of a killer at both the Beluga River and Tuxedni Bay.

From morphology, behavior, and the small group sizes described in sighting reports, it would 

appear the killer whales observed in upper Cook Inlet are a transient (marine mammal eating) 

group. The frequency of sightings in upper Cook Inlet is very low; therefore, killer whales 

observed in the upper Inlet apparently center their range elsewhere. Killer whales have stranded 

at least four times in Turnagain Arm since 1990: in May 1991, August 1993, September 2000, 

and August 2002. During the 1993 stranding event, a large male killer whale regurgitated pieces 

of beluga and harbor seal (Shelden et al. 2003) and subsequently died. 

The number of different killer whales that use the upper Inlet is not known but appears to be 

small. Photographs taken of killer whales that stranded in Turnagain Arm in 1991, 1993, and 

2000 provide evidence that the same adult male was sighted in both 1991 and 1993 (Shelden et 

al. 2003). Poor quality of additional photographs precluded the identification of other

individuals, but they do suggest that the composition of the killer whale pod during these three

encounters was similar and the same individuals may be involved in each event. No matches 

were found between the images of killer whales in Turnagain Arm and those in all available 

catalogs for Alaska south to Mexico (Shelden et al. 2003).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-40

Table 4. Reported killer whale observations in upper Cook Inlet, and reports of killer whale predation on CI

belugas Inlet-wide, 1982–2016.

Year

Reported location of 

killer whale sighting 

/ predation eventa

No. reported killer whale 

sighting / predation events in 

upper Cook Inlet

(including events in mid and lower 

Cook Inlet if associated with a 

potential predation event)

No. reported 

killer whales 

observed per 

sighting eventb

No. beluga mortalities 

suspected to be a direct 

result of killer whale 

predationb

1982 Knik Arm 1 5 0

1983 No Reports 0 0 0

1984 No Reports 0 0 0

1985 Turnagain Arm 1 1 UNK

1986 No Reports 0 0 0

1987 No Reports 0 0 0

1988 No Reports 0 0 0

1989 No Reports 0 0 0

1990 Chickaloon Bay 1 >3 1

Fire Islandc 1 4 0

1991 Turnagain Arm 1 6 0

1992 Kenai River (1) 6 0

1993 Turnagain Arm 1 5 1

1994 Susitna River 1d UNK 0

1995 Ivan River 1 3 0

1996 Ivan River 1 UNK 0

1997 Ivan River 1 UNK 0

1998 Ivan River 1 UNK 0

Port MacKenzie to 

Fire Island

1 3 0

1999 Turnagain Arm 1 3 0 

Ivan River 1 UNK 0

Chinitna Bay (1) 1 1 (2)

e

2000 Turnagain Arm 1 3–5 2 (4)

e

Kenai River (1) 3 1

Kachemak Bay (1) 1 UNK

2001 Turnagain Arm 1 1 0

2002 Turnagain Arm 3 1 0

Knik Arm 1 1 0

Chuitna River 1 2 0

2003 Knik Arm 1 2 1

2004 No Reports 0 0 0

2005 No Reports 0 0 0

2006 No Reports 0 0 0

2007 Turnagain Arm 1 3 0
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-41

Year

Reported location of 

killer whale sighting 

/ predation eventa

No. reported killer whale 

sighting / predation events in 

upper Cook Inlet

(including events in mid and lower 

Cook Inlet if associated with a 

potential predation event)

No. reported 

killer whales 

observed per 

sighting eventb

No. beluga mortalities 

suspected to be a direct 

result of killer whale 

predationb

2008 Tyonek 1 2 0

Turnagain Arm 1 2f 1

2009 Turnagain Arm 1 6 0

2010 Point Possession 2 4–5 and 3 1g

2011 Turnagain Arm 1 1 0

2012 No Reports 0 0 0

2013 No Reports 0 0 0

2014 No Reports 0 0 0

2015 Knik Arm 2 1 and 1 0

2016 No Reports 0 0 0

Totals: 1982–2016 35

(31 upper CI + 4 mid-lower CI)

Total: 77+

Average: 2–3

9

(12 if potentially dependent 

calves included)

a A predation event is defined as an event during which killer whales were observed chasing belugas, catching belugas, or when a beluga carcass 

was found with evidence of killer whale tooth marks on it.

b UNK = the information is unknown, undetermined, or unreported

c

Year of sighting estimated; this report was from Shelden et al. (2003) and was based upon an anecdotal report of a killer whale sighting in the 

“early 1990s.”

d This was an unconfirmed sighting of killer whales in the area of the Susitna River; see Shelden et al. (2003) for more details.

e These reports suggest that a dependent calf may have been present. Although there is no evidence the calf was killed, we assume the calf may 

also have died, either as a direct predation event or due to the death of its mother; thus, we have reported the number of mortalities as a range (1–

2) indicating the possibility that a mom/calf pair died.

f This sighting of killer whales may have been the same two killer whales previously reported near Tyonek.

g The necropsy report for this beluga mortality indicated that killer whale predation may have been a possible cause of death, but poor body 

condition of the beluga carcass prevented a positive determination.

Sources: Moore et al. 2000, Shelden et al. 2003, Vos and Shelden 2005, NMFS, unpub. data. (Level A stranding and necropsy reports)

Between 1982 and 2016, NMFS received 31 reports of killer whales in upper Cook Inlet, 4 

reports of killer whales possibly preying on CI belugas in mid- and lower Cook Inlet, and 9–12

CI beluga mortalities Inlet-wide suspected to be a direct result of killer whale predation (Table 

4). The 9–12 CI beluga mortalities suspected to be a direct result of killer whale predation were 

identified based upon evidence of predation observed on beluga carcasses or eye witness reports.

We present this number as a range to indicate our uncertainty regarding the fate of three calves 

still dependent upon their mothers, which were killed by killer whales. However, there is no 

evidence available to document the deaths of these three calves.

A review of the original sightings reports has resulted in a change of opinion about some 

mortalities originally attributed to killer whale predation. Shelden et al. (2003) reported that two 

CI belugas died on October 6, 1992 with “killer whale teeth marks on their flukes.” Although 

there were reports of killer whales in the Kenai River in September 1992, a review of the original 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-42

Level A stranding reports17 for the two belugas reveal that there were “no gross injuries” 

observed and no mention of killer whale teeth marks on either beluga. A comparison of the 

photographs taken of the October 1992 beluga carcasses against photographs of CI beluga 

carcasses with confirmed killer whale teeth marks from 2000 led NMFS AKR to determine that 

the whales stranded in the Kenai River in October 1992 were “not attacked by killer whales” 

(NMFS, unpub. data; Level A stranding report). Additionally, Moore et al. (2000) reported that 

in early September 2000 a CI beluga carcass was documented near Nikiski with “possible orca 

teeth marks” (reproduced in Shelden et al. 2003). However, after review of the original Level A 

stranding report, NMFS AKR confirmed the report never mentioned possible orca (a.k.a., killer 

whale) teeth marks, and given that the report states the whale was “very decomposed”, “skeletal 

remains were visible”, and it was “too deteriorated to collect skin for genetics” testing, there 

would be too little skin available to see teeth marks from a killer whale. Despite the person 

reporting the dead whale speculating that a “killer whale took bites from its belly”, without 

evidence supporting killer whale predation, the stranding event in Nikiski in 2000 cannot be 

deemed to be the result of killer whale predation. Finally, Shelden et al. (2003) indicated “killer 

whale teeth marks [were] evident” on a dead beluga found June 20, 1991, based on a report by 

Moore et al. (2000) that the beluga was found with teeth marks and a piece of its tail missing.

However, after review of the original Level A stranding report, NMFS AKR found that the 

“bitemark” noted in the report was qualified as “may have been.” Without additional 

corroborating information, there is insufficient evidence to deem this stranding to be the result of 

killer whale predation. Thus, although previously considered evidence of killer whale predation 

on CI belugas (see Moore et al. 2000 and Shelden et al. 2003), the mortalities from June 1991,

October 1992, and September 2000 are not included in Table 4 as mortalities suspected to be the 

direct result of killer whale predation.

Since 2001, only three CI beluga deaths have been suspected to be a result of killer whale 

predation: one in Knik Arm in August 2003; one in Turnagain Arm in September 2008; and one 

near Point Possession in June 2010. However, the 2010 mortality necropsy report stated although 

predation was a possible cause of death, it could not be positively determined due to the poor 

condition of the beluga carcass.

Killer whales in the vicinity or actively chasing belugas could also cause CI belugas to strand

alive. Such events may have contributed to several more CI beluga mortalities beyond those 

listed in Table 4 (strandings are discussed in the next section). For instance, in August of 1999, 

approximately 60 belugas live stranded in Turnagain with reports of killer whales in the vicinity 

prior to the stranding. Five mortalities were associated with that stranding event. However, in the 

absence of trained observers documenting killer whales’ pursuit of belugas directly to the 

location of a stranding, it is not possible to definitively attribute a mortality after a live stranding 

event to killer whale predation without physical evidence of predation on the carcass. Therefore, 

any mortalities associated with a live stranding event, despite reported killer whale presence in 

the area, are not included in Table 4.

There have been anecdotal reports and other observations of killer whales attacking or 

chasing CI belugas in lower Cook Inlet when belugas were more frequently observed in lower 

 

17 Level A stranding report forms are the forms used by NMFS to document stranding-related events.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-43

Cook Inlet. For instance, one person reported in 2002 that in 1999 they saw a killer whale 

dragging an adult beluga by its flipper from Chinitna Bay into deeper water, with the beluga’s 

calf following; and another person recalled seeing a killer whale chasing a beluga in Kachemak 

Bay in 2000 (Shelden et al. 2003; included in Table 4). Hobbs and Shelden (2008) and NMFS 

(2008a) also reported that killer whales chased and fed on a beluga near Anchor Point on June 

14, 2007. However, after follow-up interviews and a review of additional photos and video, it 

was determined that it was a minke whale that was killed by killer whales near Anchor Point, and 

not a CI beluga. 

In directed killer whale surveys in lower Cook Inlet in July 2008 and July 2009, there were 

eleven encounters with resident type killer whales (fish-eaters) and five encounters with transient 

type killer whales (mammal-eaters; Matkin et al. 2009). During these directed, and other 

opportunistic, observations of killer whales in lower Cook Inlet, transient killer whales were 

recorded killing minke whales, harbor porpoises, and harbor seals, and attacking sea otters and 

humpback whales (Matkin et al. 2009; C. Matkin, North Gulf Oceanic Society, unpub. data). No 

beluga predation was observed during directed or opportunistic observations by researchers or 

the public in the lower Inlet during this time period (Matkin et al. 2009).

CI belugas may also be susceptible to shark predation, although attacks have not been 

witnessed, nor has clear evidence of shark predation been documented. Wounds from possible 

shark attacks have been observed in photographs of CI belugas (T. McGuire, LGL, unpub. data). 

Salmon sharks and Pacific sleeper sharks are found in Cook Inlet, although neither has been 

determined to attack free-swimming cetaceans. Salmon shark jaw and tooth structure is 

indicative of a fish predator and it is highly unlikely they would attack a marine mammal (K. 

Goldman, Alaska Department of Fish and Game [ADF&G], pers. comm.to C. Goertz). Pacific 

sleeper sharks are known to feed on whale carcasses (Barrett-Lennard et al. 2011), and although 

cetacean remains have been found in their stomachs, this was apparently the result of scavenging 

and conclusive evidence of predation on live cetaceans is lacking (Sigler et al. 2006). A 

counterpart in the Atlantic Ocean, the Greenland shark, apparently consumes live pinnipeds 

(Sigler et al. 2006), but is not known to be a predator of free swimming cetaceans. It is possible 

that great white sharks make rare visits to the area (Martin 2005), but they are very unlikely to 

pose a threat to belugas due to their rarity.

b. Strandings

CI beluga strandings include beached or floating carcasses as well as live animals found in 

waters too shallow to permit them to swim. An extensive review of the NMFS AKR Level A 

stranding reports resulted in some updates to the CI beluga stranding data presented in Moore et 

al. (2000), Vos and Shelden (2005), and NMFS (2008a and 2008b). The total number of CI 

beluga carcasses reported in Table 5 reflects the most current information available regarding the 

number of reported, non-subsistence related mortalities since 1988.

Beluga whale live strandings in upper Cook Inlet are not uncommon, with a majority 

occurring in Turnagain Arm and Knik Arm (Table 5). Live stranded whales are often 

opportunistically spotted from the Seward Highway off of Turnagain Arm, or from small aircraft 

traveling over Cook Inlet. Between 1988 and 2016, 214 dead CI belugas were reported, and at 

least 876 belugas were involved in live strandings in Cook Inlet (some individual belugas were 

likely involved in multiple live stranding events over the years; Table 5). Mass strandings 

(involving two or more whales) primarily occurred in Turnagain Arm and often coincided with 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-44

Table 5. CI beluga stranding records (for beach-cast or floating carcasses, and live strandings), 1988–2016.

Year

Total no. carcasses 

(beached or 

floating) reported 

each yeara

Date of live 

stranding eventb

Location of live

stranding eventb

No. belugas per live 

stranding event 

(suspected 

associated 

mortalities)b

1988 0 Oct 23 Turnagain Arm 27 (0)

1989 5 NA NA NA

1990 2 NA NA NA

1991 1 Aug 31 Turnagain Arm 70–80 (0)

1992 5 Oct 3 Kenai River 2 (2)

1993 2 Jul 6 Turnagain Arm 10+ (0)

1994 8 Jun 14 Susitna River 186 (0)

1995 3 NA NA NA

1996 12 Jun 12

Aug 28

Sep 2

Sep 8

Oct 2

Susitna River

Turnagain Arm

Turnagain Arm

Knik Arm

Turnagain Arm

63 (0)

60 (4)

20–30 (1)

1 (0)

10–20 (0)

1997 3 NA NA NA

1998 14 May 14

Sep 17

Turnagain Arm

Turnagain Arm

30 (0)

5 (0)

1999 12 Aug 29

Sep 9

Turnagain Arm

Turnagain Arm

58–70 (5)

12–13 (0)

2000 13 Aug 27

Sep 24

Oct 24

Turnagain Arm

Turnagain Arm

Turnagain Arm

8 (0)

15–20 (0)

2 (0)

2001 10 NA NA NA

2002 10 NA NA NA

2003 20 Apr 18

Aug 28

Sep 6

Sep 14

Oct 6

Oct 17

Turnagain Arm

Turnagain Arm

Turnagain Arm

Turnagain Arm

Turnagain Arm

Ship Creek

1–2 (0)

46+ (5)

26 (0)

32 (0)

4–9 (0)

1 (0)

2004 13 NA NA NA

2005 6 Aug 24 Knik Arm 7 (1)

2006 8 Sep 12 Knik Arm 12 (0)

2007 15 NA NA NA

2008 11 Aug 7

Sep 28

Knik Arm

Turnagain Arm

28–30 (2)

20–40 (0)
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-45

Year

Total no. carcasses 

(beached or 

floating) reported 

each yeara

Date of live 

stranding eventb

Location of live

stranding eventb

No. belugas per live 

stranding event 

(suspected 

associated 

mortalities)b

2009 4 Aug 22 Knik Arm 16–21 (0)

2010 5 Aug 21

Aug 29

Knik Arm

Knik Arm

11 (0)

2 (0)

2011 3 Aug 10 Knik Arm 2 (0)

2012 3 May 8

Aug 21

Aug 29

Turnagain Arm

Turnagain Arm

Turnagain Arm

12(0)

23 (0)

3 (0)

2013 5 NA NA NA

2014 10 UNK (late May?)

Aug 23

UNK

Eagle Bay

UNK (2)c

76+ (0)

2015 3 Aug 27 Turnagain Arm 2 (0)

2016 8 NA NA NA

Total 214 876–953 (22)

a Known subsistence harvested belugas are not included.

b NA indicates there were no live strandings reported to NMFS that particular year. c On May 26, 2014 NMFS received a report of two dead belugas on the shore of Kincaid Park along Turnagain Arm; although there was no live 

stranding event reported, the necropsy of these two whales suggests they were recently live stranded and that the live stranding may have 

contributed to their death.

Source: Moore et al. 2000; NMFS 2008a, 2008b; NMFS AKR, unpub. data (CI beluga stranding database).

extreme tides or killer whale sighting reports (Shelden et al. 2003). In 2003, an unusually high 

number of beluga live strandings (five separate events in Turnagain Arm involving between 2 

and 46+ whales) and mortalities (n = 20) occurred in Cook Inlet (Vos and Shelden 2005).

Marine mammals strand alive for a variety of reasons. Belugas may intentionally ground 

themselves in shallow waters to more easily rub off molting skin, to avoid predation or other 

perceived threats (e.g., acoustic disturbances, vessel traffic, or other anthropogenic activity), 

when chasing prey, or as a result of an inability to properly navigate or maneuver when 

debilitated by injury or disease (Smith et al. 1992, Moore et al. 2000, Shelden et al. 2003, Vos 

and Shelden 2005, Burek-Huntington et al. 2015). A prolonged period out of the water may 

ensue if animals strand during outgoing tides, especially with the extreme/rapid tidal changes and 

gently sloping mudflats of Cook Inlet. The perception is that belugas tolerate such events better 

than other cetaceans due to their relatively small size and flat abdomens which spread out their 

weight and allow them to remain upright, their light color which minimizes the absorption of 

heat from sunlight, and their ability to create wallows in the mud to retain at least some water to 

help them stay cool and moist. While belugas often appear calm and seem to float off without 

incident with the incoming tide, these animals have not been assessed or tracked other than 

during the stranding itself and from a great distance. 

However, carcasses found following documented mass strandings, as well as carcasses found 

in the absence of such events, have shown evidence of death as a result of a live stranding. 

Findings from 38 CI belugas necropsied between 1998 and 2013 indicated nine died following a 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-46

live stranding (Burek-Huntington et al. 2015; note Table 5 documents a total of 13 belugas may 

have died after a live stranding event; not all of these belugas were accessible and necropsied, 

but were included in the table due to the close timing of a dead beluga with a reported live 

stranding event). Five of these nine belugas were found dead shortly after documented mass 

strandings. Some of these dead belugas appeared to have been robust and otherwise healthy, with 

no other definitive causes of death. However, they did have debris deep in their airways 

suggesting forceful inspiration of mud while alive, such as might occur during a live stranding 

(Burek-Huntington et al. 2015; NMFS AKR, unpub. data). In May 2014, two belugas found dead 

near Anchorage also had sand deposited within their airways suggesting a recent live stranding 

event (NMFS AKR, unpub. data), although no live stranding event was reported.

Four additional individual carcasses had extensive post-mortem sampling and analyses which 

did not reveal a pre-existing health problem or other cause of death; however, sand and silt was 

found in the airways, again suggesting forceful inspiration of mud as might occur during a live 

stranding. In addition to the obstructive inhalation of debris leading to asphyxia (lack of oxygen), 

live strandings could also lead to death due to stress, hyperthermia (abnormally elevated 

temperature), pressure necrosis (cellular death due to excessive pressure) of internal organs, 

aspiration pneumonia (pneumonia due to inhaled material), and kidney damage secondary to 

myopathy (muscular damage) or muscle compartment syndrome (muscular swelling constricted 

by surrounding tissue resulting in reduction of blood supply). Some of these conditions may take 

weeks to months to fully develop and cause death. They may also exacerbate pre-existing 

conditions, making it difficult to determine whether death was caused by a previous live 

stranding. Understanding the true impact of live stranding on animals that survive the ordeal 

requires a more directed assessment and tracking of those animals. Live belugas have not been 

observed to strand in SLE and deaths attributed to such events have not been identified there (S. 

Lair, pers. comm. to C. Goertz).

2. Anthropogenic Sources

a. Subsistence Harvest

Alaska Natives harvested CI belugas for cultural, subsistence, and handicraft purposes prior 

to and after passage of the MMPA in 1972. The effect of past harvest practices on the CI beluga 

population is significant, particularly the harvests of the mid-to late-1990s. While harvests 

occurred at traditional (but undocumented) levels for decades, the subsistence harvest removals 

apparently increased substantially beginning in the 1980s, with unsustainable removals in the 

1990s (Figure 14) (CIMMC [Cook Inlet Marine Mammal Council] 1996, 1997; Mahoney and 

Shelden 2000; Angliss et al. 2001; Angliss and Lodge 2002; National Oceanic and Atmospheric 

Administration [NOAA] 2007; NMFS AKR, unpub. data18). This increase in harvest numbers 

may have been the result of an increased Alaska Native population in the Cook Inlet region, with 

new participation by hunters who previously lived in areas without a traditional history of 

hunting in the Inlet.

A study conducted by ADF&G, in cooperation with the Alaska Beluga Whale Committee 

and the Indigenous People’s Council for Marine Mammals, estimated the subsistence take of 

 

18 For more information, contact NMFS AKR, Protected Resources Division.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-47

Source: Angliss and Lodge 2002; CIMMC 2007; NMFS 2008b; NMFS AKR, unpub. data.

Figure 14. Summary of reported CI beluga subsistence harvests and estimated numbers struck and lost, 1987 

to 2016.

belugas in Cook Inlet in 1993 at 17 whales. In consultation with Native Elders from the Cook 

Inlet region, the CIMMC estimated the annual number of belugas taken by subsistence hunters

during this time to be over 30 per year. However, without a complete survey of hunters, this most 

likely is a minimum estimate (Hill and DeMaster 1998; DeMaster 1995). There was no

systematic CI beluga harvest survey in 1994; instead, harvest data were compiled at the 

November 1994 Alaska Beluga Whale Committee meeting. The most thorough CI beluga 

subsistence harvest surveys, including struck and lost estimates, were completed by CIMMC 

during 1995 and 1996 (CIMMC 1996, 1997; Angliss and Lodge 2002). While there was no 

survey during 1997 or 1998, NMFS estimated the subsistence harvest from hunter reports. The 

known annual subsistence harvest by Alaska Natives during 1995 to 1998 averaged 77 belugas

per year which, in combination with struck and lost estimates, can account for the estimated 

population decline during this interval (Figure 14). The harvest was sufficiently high to account 

for the nearly 50% total decline in the population during the period from 1994 through 1998 

(Hobbs et al. 2000). Hunters have described harvest numbers and effort in the late 1980s as 

similar to the 1990s (B. Mahoney, NMFS AKR, pers. comm.). If subsistence takes prior to 1994 

were at levels approaching those recorded in the mid-1990s that potentially unsustainable level 

of take could account for the CI beluga decline from 1,300 whales to 653 whales from 1979 to 

1994. 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-48

In 1999 and 2000, Public Laws 106–31 and 106–553, established a requirement that hunting 

of CI belugas for subsistence uses by Alaska Natives must be conducted pursuant to cooperative 

agreements between NMFS and the affected Alaska Native organizations. A voluntary 

moratorium by hunters in 1999 resulted in no CI beluga harvest that year. During 2000 to 2003

and 2005 to 2006, NMFS entered into co-management agreements for the CI beluga subsistence 

harvest, limiting harvest to one or two belugas per year starting in 2000. From 2000 to 2006, 

subsistence harvests were 0, 1, 1, 1, 0, 2, and 0 belugas, respectively. There has been no 

subsistence harvest of CI belugas after 2005.

b. Commercial Whaling

A brief commercial whaling operation existed along the west side of upper Cook Inlet during 

the 1920s, where 151 belugas were killed in five years (Mahoney and Sheldon 2000). There was 

also a recreational hunt for belugas in Cook Inlet prior to enactment of the MMPA (Mahoney 

and Shelden 2000). The potential impacts of these pre-MMPA hunts on the present status of this 

stock cannot be determined.

c. Poaching or Intentional Harassment

Due to their approachable nature, the potential for poaching belugas in Cook Inlet exists. 

NOAA Law Enforcement has investigated several incidents of reported harassment of CI 

belugas, and as of September 2016, there has been one civil conviction of harassment (L. 

Cockreham, NOAA, Office of Law Enforcement, pers. comm.). There are reports and 

photographs of CI belugas with wounds consistent with harpoon or gunshot trauma (McGuire et 

al. 2011), but these animals have not been examined further, and no poaching incidents have 

been confirmed.

d. Incidental Mortalities or Injuries

The following section discusses mortalities or injuries to CI belugas incidental to the 

associated human activity. In this context, “incidental” refers to the death or injury (to include 

entanglement) of animals where death or injury was not intended. Activities with the potential to 

cause incidental injury or death include fisheries activities, vessel activities, or research projects.

There is also documented evidence of CI belugas being entangled in marine debris. This section 

does not consider injuries that may occur as a result of noises associated with human activities.

Those are discussed separately.

Fisheries activities: NMFS has only documented one CI beluga whale mortality associated 

with personal use, subsistence, or recreational fisheries (see Burek-Huntington et al. 2015). In 

May 2012, a yearling CI beluga carcass was recovered from a 60 ft subsistence set net with 8 

inch mesh located approximately 1–2 miles south of the Kenai River. Histopathological analysis 

of tissues indicated cause of death was most likely drowning. However, this animal also suffered

from severe bronchopneumonia, and it appeared unusually small for its age. The whale may have 

been unable to extract itself from the net when an otherwise healthy individual may have 

escaped. While there have been other sporadic reports over the years of single belugas becoming 

entangled in fishing nets, mortalities were not confirmed.

The only other reports of fatalities of CI belugas incidental to fishing in Cook Inlet are from 

the literature. Murray and Fay (1979) stated that commercial salmon gillnet fisheries in Cook 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-49

Inlet caught five belugas in 1979. Burns and Seaman (1986) estimated incidental take rates by 

commercial salmon gillnet fisheries in the Inlet at 3–6 belugas per year during 1981 to 1983. 

Neither report, however, differentiated between set gillnet and drift gillnet fisheries. 

NMFS placed observers in the Cook Inlet salmon drift net and upper and lower Inlet set 

gillnet fisheries in 1999 and 2000 (Angliss and Lodge 2002, Manly 2006). During the two years 

of observations, an estimated total of 384 net-days were observed for the drift gillnet fishery, and 

an estimated 614 net days were observed for the set gillnet fishery. Only three sightings of 

belugas were made at set gillnet locations in upper Cook Inlet (Moore et al. 2000). Although one 

harbor porpoise was reported dead in the Upper Cook Inlet driftnet fishery, belugas were never 

observed within 10 m (32.8 ft) of a net (i.e., within a distance categorized as an interaction) in 

the drift or set gill net fisheries; therefore, no beluga injuries or mortalities were reported from 

drift or set gillnets in either 1999 or 2000 (Manly 2006). The most likely impacts from personal 

use, subsistence, recreational, and commercial fisheries include disturbance from the operation of 

watercraft in stream mouths and shallow waters, ship strikes, displacement from important 

feeding areas, harassment, and prey competition.

Vessel activities: Ship strikes have not been confirmed, but could not be ruled out in CI 

beluga deaths caused by trauma. For example, in September 2007, a dead beluga was found to 

have a wide, blunt trauma along the right side of its chest (NMFS AKR unpub. data). While a 

cause of the trauma was not determined, it may have been caused by the animal being hit by a 

boat or other watercraft (e.g., jet ski). Additionally, there are reports and photographs of CI 

belugas with scarring patterns consistent with propeller injuries (McGuire et al. 2011).

Research activities: Passive research with a low potential to affect CI belugas may include 

aerial surveys, shore-based observations, passive acoustic studies (non-tagging), prey studies, 

habitat studies, pathology and disease studies on dead animals, and contaminant studies. Other 

research may change the behavior of, harass, injure, or kill belugas. Such activities include 

capturing belugas, applying satellite tags, applying suction cup dive tags, taking blood and 

biopsies from live animals, and any boat or in-water work that changes whale behavior or 

movements. Between 1999 and 2002, NMFS researchers captured and affixed satellite tags to a 

total of 18 CI belugas. In 2002, data from one satellite-tagged CI beluga indicated a weak swim 

pattern for 32 hours post-tagging; the whale was found floating dead a short time later and was 

positively identified by a fin tag. The beluga’s belly-up position while floating prevented 

detection of satellite tag transmissions. Two other satellite-tagged whales captured during the 

same season exhibited similarly weak swim patterns prior to the loss of the satellite tags’ signals 

less than 48 hours post-tagging. These whales were not found, but were presumed to have died 

less than 54 hours after tagging. While the available data do not conclusively point to the cause 

of death of these three belugas, NMFS concluded the most apparent explanation is that they died 

as a result of the capture and tagging activities (NMFS, unpub. data). 

Photo-identification studies by McGuire et al. (2013) reported identification of seven 

individual belugas with scarring due to satellite tags, providing evidence that at least seven of the 

previously tagged CI belugas survived at least four years after the tagging event, with five of the 

seven whales re-photographed in 2011 (McGuire et al. 2013). Five of these seven whales are 

presumed to be females based on close associations with calves (McGuire et al. 2013).

Marine debris: There have been reports of CI belugas alive, but entangled in marine debris.

In 2005, a CI beluga was photographed in Eagle Bay, entangled in an unknown object, perhaps a 
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan D. Sources of CI Beluga Mortality or Injury

II-50

tire rim or a culvert liner (McGuire et al. 2013). In 2010, 2011, 2012, and 2013, another CI 

beluga was repeatedly photographed with what appeared to be a rope entangled around the upper 

portion of its body near the pectoral flippers (McGuire et al. 2014a, 2014b). NMFS determined 

that attempts to disentangle the whale were not warranted because there was no apparent 

physical injury due to its entanglement, and the benefit of disentanglement did not outweigh the 

harassment-induced risks that such an operation would posed to that and other whales.

3. Cause of Death Analysis of Necropsied CI Belugas

Causes of death for most stranded CI belugas remain largely unknown. Post-mortem exams 

are hampered by the lack of road access and extensive hazardous tidal flats in Cook Inlet. In 

addition, the remote nature of much of Cook Inlet’s coastline preclude the timely reporting of 

carcasses suitable for necropsy and make responding with a necropsy team logistically difficult. 

Additional carcasses may go unexamined because animals may sink after dying or be surrounded 

by winter ice and swept out of the Inlet prior to detection. From 1998 to 2013, only 38 carcasses 

out of 164 observed dead stranded belugas were subjected to some degree of post-mortem 

examination or necropsy (Burek-Huntington et al. 2015). Necropsied belugas were concentrated 

close to Anchorage and along the road system. Burek-Huntington et al. (2015) reviewed the 

causes of morbidity and mortality determined from these examinations. A more detailed

discussion of the necropsy analyses from 1989–2009 is provided in Appendix IX.H – Cause of 

Death Analysis.

Of the 38 CI beluga carcasses examined from 1998 to 2013, a primary cause of death was not 

identified in 29% of the cases, primarily because most carcasses were in an advanced state of 

decomposition (Burek-Huntington et al. 2015). Identification and reporting of strandings, both 

live and dead, as well as the subsequent responses, need to be accelerated and enhanced in order 

to obtain the quality information necessary to understand the causes of morbidity and mortality 

in CI belugas. Nevertheless, it is often difficult to determine a cause of death even when 

carcasses are examined promptly under laboratory conditions. Conditions identified as a primary 

cause of death in CI belugas included previous mass or single live stranding (24%), trauma 

(18%), perinatal mortality (13%), malnutrition (8%), and disease (8%). Factors considered 

contributory to mortality (i.e., findings not assigned as a primary cause of death) included 

disease, aspiration of glacial silt and/or stomach content, malnutrition, and trauma. It has been 

noted that the number of documented mortalities of CI belugas seems to be equivalent to that of 

belugas in the St. Lawrence Estuary in Canada (P. Béland, St. Lawrence National Institute of 

Ecotoxicology, unpub. data), which has a much larger estimated population size of about 889

individuals (COSEWIC 2014).
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan E. Section Summary

II-51

E. Section Summary: Background

Cook Inlet

Cook Inlet is a semi-enclosed tidal estuary located in southcentral Alaska and is 

approximately 370 km (230 mi) in length and extends in a northeast/southwest orientation from 

Knik and Turnagain Arms in the north to the southernmost reaches of Kamishak Bay in the 

south. Considerable amounts of sediment are naturally deposited into Cook Inlet, creating a 

highly turbid, low visibility environment, particularly in the northern portion of the Inlet. Cook 

Inlet experiences some of the greatest tidal fluctuations in the world, with the difference between 

high and low tide levels reaching 12 m (39 ft). These large tidal ranges, combined with broad 

tidal flats, can result in currents reaching 6.2 m/sec (20.3 ft/sec). In winter, ice covers much of 

upper Cook Inlet as rivers begin to freeze in October and November.

Relevant CI Beluga Life History

In Alaska, there are five recognized beluga stocks delineated based on summer range: the 

Beaufort Sea, the eastern Chukchi Sea, the eastern Bering Sea, Bristol Bay, and Cook Inlet. The 

degree of genetic differentiation among the Cook Inlet stock and the other four Alaska beluga 

stocks indicates CI belugas are the most isolated reproductively and demographically. This 

isolation is long established, resulting in localized adaptation and indicating that the possibility 

of rescue from neighboring populations is remote.

CI belugas are unique in Alaska given that their habitat is in close proximity to the greatest 

concentration of Alaska’s human population. Belugas are not uniformly distributed throughout 

Cook Inlet, but are predominately found in nearshore waters of the upper Inlet. Humans use the 

waters and shores of Cook Inlet for fishing, hunting, timber harvest, mining, shipping, dredging, 

renewable energy production, wastewater discharge, military activities, oil and gas development, 

transportation, and residential and industrial development.

The distribution of CI belugas has changed significantly since the 1970s; as their population 

declined, their summer range has contracted to the upper Inlet. Belugas spend the summer and 

early fall months in the upper Inlet, concentrating at river mouths. In late fall, belugas disperse 

south into the middle Inlet and into deeper offshore waters. This pattern continues through 

winter, when whales exhibit the most wide-ranging movements, spanning both nearshore and 

offshore waters from the upper reaches of Knik Arm to the middle Inlet. Large aggregations of 

belugas in specific areas of upper Cook Inlet during May to October likely indicate a critical time 

period for foraging; it is during the ice-free months that calves are born and nursed and that the 

whales acquire the thick blubber layer they will need to survive through the winter months. In 

addition to comprising important feeding habitats, the shallow waters of the upper Inlet may also 

play important roles in reproduction. Other critical uses of habitat by CI belugas may include 

avoidance/escape from predators, transiting among feeding and/or nursery habitats, and refuge 

from human activities (e.g., in-water noise, ship traffic and hunting).

Belugas have low reproductive potential; that is, females have a single calf only every two or 

more years, and devote considerable time to caring for their young. Age at sexual maturity, 

length of gestation, and calving interval are unknown for CI belugas. Data are not available for 

CI belugas to precisely determine the generation time; however, when we consider available 

information regarding the age at first reproduction and age at senescence for belugas, we 

estimate a generation time of approximately 25 years.
Cook Inlet Beluga Whale II. BACKGROUND

Recovery Plan E. Section Summary

II-52

Belugas make a wide variety of sounds and have highly developed echolocation capabilities. 

Their high auditory sensitivity, wide frequency bandwidth, and dependence upon sound to 

navigate, communicate, and find prey and breathing holes in the ice make belugas vulnerable to 

noise pollution, which may mask beluga signals or lead to temporary or permanent hearing 

impairment.

Belugas are extremely social animals that typically travel and hunt together. High group 

cohesion and large group sizes may provide benefits to group members in terms of information 

gathering and transfer with regard to resource availability (e.g., prey, calving sites, 

oceanographic conditions, etc.) and cooperation in predator avoidance and reduced predation 

risk. The evidence available for CI belugas suggests that individual belugas intermix and interact 

with various beluga groups across the Inlet.

The diet of CI belugas is dominated by fish and invertebrates. Recent analysis suggests CI 

beluga diets changed in the last few decades and whales have been feeding at lower trophic 

levels. Pacific salmon, including Chinook (king) salmon, are an essential feature of CI beluga

critical habitat. There is therefore concern that recent reductions in run strength of Chinook 

salmon stocks across Alaska, particularly in Cook Inlet, may be affecting CI belugas.

CI Beluga Whale Population Size and Trends

Aerial surveys in the 1960s, 1970s, and early 1980s counted belugas in Cook Inlet but only a 

few of these had sufficient coverage to estimate the population size. A 1979 survey resulted in an 

estimate of 1,293 belugas in Cook Inlet; NMFS has adopted 1,300 belugas as the value for the 

carrying capacity to be used for management purposes. Between 1979 and 1994 the CI beluga 

population declined roughly 5% annually from about 1,300 whales to 650 whales. Between 1994 

and 1998 the population declined nearly 50% from 650 whales to 347 whales, likely a result of 

unsustainable levels of subsistence harvest. Since 1999, when subsistence hunting was restricted, 

the population has continued to decline by 1.3% per year. The 2014 abundance estimate was 340

CI belugas.

Sources of Mortality or Injury

In the past, there have been both natural and anthropogenic sources of mortality or injury of 

CI belugas. Natural sources include predation by “transient” killer whales, live strandings, and 

potentially disease; anthropogenic sources include subsistence harvest, poaching or intentional 

harassment, and mortalities or injuries incidental to other human activities. Although the cause of 

death for most CI belugas remains unknown, 38 CI belugas were necropsied between 1998 and 

2013; identified causes of death included association with previous mass or single live 

strandings, trauma, perinatal mortality, malnutrition, and disease.
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan

III-1

III.THREATS TO RECOVERY

While the recent downward trends in CI beluga abundance and range are well documented, 

little is known about the mechanisms impeding recovery. Previous hypotheses for the delay in 

recovery include: 1) reduced fecundity because the mature female segment of the population is 

depleted; 2) reduced fecundity or survival due to potential population-wide stressors such as 

reduced prey, contaminants, disease, or inbreeding effects; 3) loss of whales as a result of 

predation by killer whales or stranding events; and 4) risks associated with contracting range and 

grouping behavior of the whales (NMFS 2008a). A population model that implicitly considered 

the time lags inherent in long-lived populations where sexual maturity does not occur for many 

years (Litzky 2001; Hobbs and Shelden 2008) indicated that the depletion of females is an 

unlikely cause for the current continued decline. While concluding that other effects besides the 

subsistence hunt have contributed to the decline and failure to rebuild, the population model was 

unable to narrow down the causal effects using the available data (Hobbs and Shelden 2008). 

The model also projected population abundance into the future and demonstrated that extinction 

risk varied considerably under different scenarios of risk factors for CI belugas. A more recent 

PVA reached similar conclusions (Hobbs et al. 2015c)

The following section examines potential obstacles to the recovery of CI belugas. It is 

unlikely that all threats listed in this recovery plan impact CI beluga recovery equally, so ideally 

each threat would be investigated and either dismissed as insignificant or prioritized for action 

according to defined criteria. Table 6 lists each threat and summarizes our assessment of the 

major effect of the threat, its extent, frequency, trend, probability, magnitude, and rating of 

relative concern (among the threats identified) for CI beluga recovery (definitions of these terms 

are provided in Table 6). Assessments were made based on the information and data gaps 

presented in the Background section of this recovery plan. 

Climate change, while considered a potential threat to CI beluga recovery, is not addressed as 

a separate threat in this recovery plan, but rather is discussed with respect to how it may affect 

each of the listed threats. Although climate change occurs naturally, the effects of greenhouse 

gas emissions are fundamentally changing global processes. This recovery plan does not attempt 

to identify the sources of such emissions or to assess the relative contribution of each potential 

source. Instead it focuses on the effects of a changing climate to CI belugas. For example, 

climate change may result in increased frequency and intensity of storms and droughts, and these 

events can have effects on belugas. Thus, since we are assessing effects of climatic changes to 

the species and not the causes of climatic changes, in many instances in this recovery plan 

climate change is referenced as a factor that affects natural events, even though we acknowledge 

that certain natural events may be exacerbated by human-induced climate change.

As previously discussed (see Section II.C.3. Small Population Dynamics), there are inherent 

risks associated with small populations, such as loss of genetic or behavioral diversity. The 

effects of threats on small populations may be greater than on large populations due to these

inherent risks. Small populations may be more susceptible to disease, inbreeding, predator pits, 

or catastrophic events than large populations. In this section, we address ten principal threats to 

the CI beluga population and consider how they may be exacerbated by these types of inherent 

risks due to small population size.

Section 4(a)(1) of the ESA and the associated regulations (50 CFR Part 424) set forth the 

following considerations for the listing status of a species: 1) the present or threatened 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan

III-2

destruction, modification, or curtailment of its habitat or range; 2) overutilization for 

commercial, recreational, scientific, or educational purposes; 3) disease or predation; 4) 

inadequacy of existing regulatory mechanisms; or 5) other natural or human-made factors 

affecting its continued existence. In the 2008 decision to list CI belugas as endangered, NMFS 

cited all five ESA section 4(a)(1) factors (73 FR 62919). In Table 6, the ten threats identified 

below are associated with the relevant ESA section 4(a)(1) factors (identified as Factors A–E).
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan

III-3

Table 6. Summary of threats assessment for CI belugas.

Threat Type

ESA § 4(a)(1)

factor Major effect Extent Frequency Trend Probability Magnitude

Relative

concern

Catastrophic events 

(e.g., natural disasters; 

spills; mass 

strandings)

A, D, E Mortality, compromised 

health, reduced fitness, 

reduced carrying capacity

Localized Intermittent & 

Seasonal

Stable Medium to 

High

Variable

Potentially High

High

Cumulative effects C ,D, E Chronic stress; reduced 

resilience

Range wide Continuous Increasing High Unknown 

Potentially High

High

Noise A, D, E Compromised 

communication & 

echolocation, 

physiological damage, 

habitat degradation

Localized & 

Range wide

Continuous, 

Intermittent, & 

Seasonal

Increasing High Unknown 

Potentially High

High

Disease agents (e.g., 

pathogens; parasites; 

harmful algal blooms)

C Compromised health, 

reduced reproduction

Range wide Intermittent Unknown Medium to 

High

Variable Medium

Habitat loss or 

degradation

A Reduced carrying 

capacity, reduced 

reproduction

Localized & 

Range wide

Continuous & 

Seasonal

Increasing High Medium Medium

Reduction in prey A, D, E Reduced fitness 

(reproduction and/or 

survival); reduced 

carrying capacity

Localized & 

Range wide

Continuous, 

Intermittent, & 

Seasonal

Unknown Unknown Unknown Medium

Unauthorized take A, E Behavior modification, 

displacement, injury or 

mortality

Range wide, 

localized 

hotspots

Seasonal Unknown Medium Variable Medium

Pollution A Compromised health Localized & 

Range wide

Continuous, 

Intermittent, & 

Seasonal

Increasing High Low Low

Predation C Injury or mortality Range wide Intermittent Stable Medium Low Low

Subsistence hunting B, D Injury or mortality Localized Intermittent Stable or 

Decreasing

Low Low Low
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan

III-4

Definitions used in Table 6 - Summary of threats assessment for CI belugas:

ESA §4(a)(1) factor: The ESA factors NMFS relied upon for listing CI belugas (73 FR 62919,

October 22, 2008)

A: The present or threatened destruction, modification, or curtailment of its habitat or range

B: Overutilization for commercial, recreational, scientific, or educational purposes

C: Disease or predation

D: The inadequacy of existing regulatory mechanisms

E: Other natural or manmade factors affecting its continued existence

Major effect: A brief description of immediate/proximate/primary effect of the threat on a 

biological process or the mechanism by which it impacts belugas. Ultimately all threats have an 

impact on fitness, reproduction, and/or mortality, but often there is an immediate effect on a 

specific aspect of life history, which is listed here.

Extent: The portion of the CI beluga range over which the threat is found.

Range wide: The threat occurs throughout the CI beluga distribution. 

Localized: The threat is primarily found in only a portion of the range, or is present at low levels 

throughout the range but is greatest in discrete areas.

Frequency: The occurrence/regularity of the threat over time.

Continuous: The threat is relatively constant through the year.

Seasonal: The threat is greatest during specific seasons, but may occur at other times of the year.

Intermittent: The threat may occur at any time of the year or at irregular/sporadic intervals not 

associated with specific seasons or time frequencies.

Trend: The change in frequency or intensity of a threat over time; described as increasing, 

decreasing, stable, or unknown.

Probability: Qualitative description of the chance of a threat occurring in the future.

Magnitude: Describes the perceived qualitative impact of the threat (if it were to occur) on the 

CI beluga whale population. 

Relative concern: The overall perception of how a threat affects CI beluga recovery, after 

accounting for other parameters listed in the table.
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-5

A. Discussion of Threat Types

The ten potential threat types discussed below were identified as having a low, medium, or 

high level of relative concern for affecting the CI beluga population (see Table 6). Information 

presented in this section is summarized in Table 6, and is used to determine the relative concern 

of each threat type to the CI beluga population. The identified threat types and their level of 

relative concern are:

• Catastrophic events (relative concern: high);

• Cumulative effects of multiple stressors (relative concern: high);

• Noise (relative concern: high);

• Disease agents (relative concern: medium);

• Habitat loss or degradation (relative concern: medium);

• Reduction in prey (relative concern: medium);

• Unauthorized take (relative concern: medium);

• Pollution (relative concern: low);

• Predation (relative concern: low); and

• Subsistence hunting (relative concern: low).

1. Threat Type: Catastrophic Events

A catastrophic event in Cook Inlet may be the result of a natural or anthropogenic event. 

Regardless of source, the potential for injury or mortality of CI belugas exists. A catastrophic 

event could directly affect CI belugas (e.g., harm due to spilled contaminants), or could 

indirectly affect them through effects upon their habitat or prey. A catastrophic event may also 

be a contributing factor to a mass stranding event. A mass stranding resulting in numerous 

mortalities would be catastrophic to the recovery of CI belugas; as such, we consider mass 

strandings as a potential catastrophic event. 

a. Potential Sources of a Catastrophic Event

Several natural factors may result in a catastrophic event with potential to adversely affect CI 

belugas, including effects from environmental or climatic changes, earthquakes, volcanos, 

disease outbreaks, lethal mass strandings, and failures of key salmon runs. Anthropogenic events, 

such as oil spills and natural gas blowouts, may also have detrimental effects on CI belugas.

Catastrophic events may also affect CI beluga prey, whether through changes to spawning or 

migration patterns, direct mortality, or potential long-term sub-lethal impacts (Moles et al. 1994; 

Marty et al. 1997; Murphy et al. 1999).

The State of Alaska maintains a record of all spills of harmful substances. From 1994 to 

2011, there were 255 events in or near Cook Inlet releasing more than 100 gallons or 100 lb 

(378.5 liters or 45.4 kg) of reportable substances (Alaska Department of Natural Resources, 

Division of Oil & Gas, 2011, unpub. data). These spills included 90 events releasing a total of 

84,195 gallons (318,713 liters) of various types of oils (diesel, hydraulic, gasoline, engine lube, 

aviation fuel, and natural gas); 48 events releasing a total of 25,404 gallons (96,165 liters) and 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-6

11,364,847 kg (25,055,199 lb) of hazardous materials (bases or alkaline substances, drilling 

muds, glycols, and urea); and 73 events releasing 110,332 kg (243,241 lb) and 1,574 gallons 

(5,958 liters) of extremely hazardous substances (anhydrous ammonia, hydrochloric acid, and 

sulfur dioxide). The most significant events releasing more than 10,000 lb or 10,000 gallons 

(4,536 kg or 37,854 liters) are listed in Table 7 (Alaska Department of Natural Resources, 

Division of Oil & Gas, 2011, unpub. data). There are no reports of CI belugas being directly 

impacted by any of these events.

Belugas may live-strand in response to a variety of natural and anthropogenic stimuli that 

may occur singly or in combination, including predator avoidance, chasing prey, changes in 

water flow, disease, illness, injury, acoustic events, or catastrophic events. Belugas are usually 

able to survive through a live stranding event and escape to deeper water on the rising tide.

However, some deaths have occurred from these events (see Table 5). If a large number of 

mortalities were associated with a live stranding, the effects on the population could be 

catastrophic. Fortunately, mortalities associated with a live stranding event do not appear to be 

common. The last mortalities suspected to be associated with a live stranding event were in May 

2014 when two CI belugas were found dead with evidence of glacial silt in their lungs (NMFS 

AKR, unpub. data). Although NMFS received no reports of a live stranding, the presence of silt 

in the airway is indicative of a likely live stranding event. Prior to 2014, the last suspected

mortalities from a live stranding event were in 2008 (Table 5). For the purposes of this section, 

we would consider mass mortalities associated with a live stranding as a catastrophic event.

b. Relative Concern

Effects from catastrophic events are variable, ranging from mortality to compromised health 

or injury to individual whales, reduced overall fitness or resilience of the population, or reduced 

carrying capacity of the environment. A catastrophic event resulting in CI beluga mortality will 

increase the likelihood of extinction, currently projected at 0–14% probability in the next 100

years (Hobbs et al. 2015c). A catastrophic event in which only carrying capacity was affected

will likely have minimal impact to CI belugas because the population (300–400) is small 

compared to carrying capacity (K = at least 1,300). Compared to other effects of catastrophes, 

decreased survival and fecundity have a much greater impact on recovery than does a decrease in 

carrying capacity. For example, an anthropogenic spill of some chemical in a marginal area of 

habitat would result in limited exposure of CI belugas to that chemical. However, a spill in a

more centrally located area will increase the exposure of CI belugas and increase the severity of 

the impact, to the point recovery of the population could be delayed (Hobbs et al. 2009).

Small populations, such as CI belugas, may be more susceptible than large populations to 

adverse effects resulting from catastrophic events. The reduced summer range of CI belugas into 

the upper Inlet makes them vulnerable to catastrophic events that have the potential to kill or 

injure a significant portion of the population. It is expected that most catastrophic events would 

be localized events, affecting only a portion of the CI belugas’ range. However, depending on the 

location of the event, the exposure or effect to the whales will vary. With the exception of live 

strandings, a catastrophic event in lower Cook Inlet which occurs in the summer when most CI

belugas are in the upper Inlet will have less effect than if the same event were to occur during 

summer in the upper Inlet. Fortunately, the frequency of catastrophic events in Cook Inlet has 

been low, and such events occur only intermittently. Although past experience indicates the 

frequency of catastrophic events is low, anthropogenic activity in Cook Inlet is increasing,
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-7

Table 7. Events releasing more than 10,000 pounds or gallons of reportable substances into Cook Inlet, 1994–

2011.

Year

Spill 

name/description Region Quantity Unit Substance

Refineries, pipelines, and production

2003 to 2008 Agrium Ammonia Nikiski 78,123 Pounds Ammonia, 

anhydrous

37 Events

2008 Aurora Gas 

Moquawkie

West Kenai 11,000 Gallons Drilling mud

2004 Marathon 

Beaver Creek Fire

Beaver Creek Field 21,000 Gallons Natural gas 

liquid

1995 to 1996 UNOCAL Central Kenai 57,940 Pounds Ammonia, 

anhydrous

16 events

2008 to 2009 Tesoro Refinery SO2 Nikiski 104,595 Pounds Sulfur dioxide

13 Events

1999 UNOCAL SRF Swanson River Field 10,500 Gallons Produced watera

Vessels

1997 Crowley Oregon 

Barge

South Cook Inlet 25,000,000 Pounds Urea (solid)

a The water produced when oil and gas are extracted from the ground.

Source: Alaska Department of Natural Resources, Division of Oil & Gas, 2011, unpub. data.

and environmental and climatic conditions are changing; accordingly, we infer that the 

probability of a catastrophic event occurring in the future will be higher than it has been, and 

thus we categorize this probability as medium to high. The magnitude of effect of a catastrophic 

event on CI belugas is assumed to be variable and dependent upon several factors including type 

of event, location of event, timing of event, and exposure of whales to the event. However, we 

ranked the magnitude as variable, but potentially high given the fact that mortalities from live 

strandings or other catastrophic events would have a greater and more immediate adverse effect 

on the recovery potential of the population than other types of effects (e.g., behavior 

modification; reduced carrying capacity). When we consider all these factors, we conclude the 

overall relative concern of the impact of catastrophic events on CI belugas to be of high concern.

2. Threat Type: Cumulative Effects of Multiple Stressors

a. Potential Cumulative Effects of Multiple Stressors

While it is difficult to quantify or characterize individual stressors, it is even more difficult to 

quantify the potential impacts that a combination of stressors, either concurrently or sequentially, 

would have on CI beluga recovery. Exposure to any given stressor at a sub-lethal level may 

predispose individual belugas to greater susceptibility to mortality or long-term effects (e.g., 

reproductive failure) from other stressors. 

Anything that affects the probability of reproduction or survival of an individual affects that 

individual’s fitness. Death can also result from different combinations and intensities of multiple 

stressors. Because body condition (one measure of health) varies among individual whales, 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-8

deaths observed from the cumulative effects of multiple stressors are likely to occur over a 

period of time rather than as a single instantaneous event as progressively less robust individuals 

succumb. However, peaks in mortalities are likely to be associated with periods of greatest 

stress, such as over winter or during the birthing/nursing season. Environmental factors can also 

interact with other factors to impact beluga whale health. For example, a reduction in availability 

of preferred, high-lipid prey, such as salmon, will reduce individual body condition, increasing 

susceptibility to parasites, disease, and predation, and possibly reduce reproductive potential. 

Also, a period of restricted food access can cause belugas to use their fat reserves, resulting in 

the short-time release into the blood stream of contaminants that may have bioaccumulated in 

that tissue (Couillard et al. 2008a; Couillard et al. 2008b).

Cumulative impacts have been a long-standing issue in the debate over noise effects on 

marine mammals (Clark et al. 2009). The additive effects of multiple noise sources, as well as 

the combination of noise and other stressors, are of particular concern, but this field remains 

poorly understood (NRC 2005, Kuczaj 2007).

Cumulative effects include synergistic effects in which two stressors interact to cause greater 

harm than the sum of the effects of the individual component stressors. This is particularly 

relevant for marine mammals, including CI belugas, because potential cumulative effects are not 

well-understood in marine mammals generally and in CI belugas specifically. However, 

available scientific data, discussed below, highlights the concerns surrounding these potential 

cumulative effects, some of which are tied to stressors that are present in CI beluga habitat (e.g., 

chemicals, noise, presence of predators).

For example, there is the potential for synergistic effects occurring as a result of co-exposure 

to certain chemical pollutants and noise. Ototoxins are substances that temporarily or 

permanently damage hearing. These chemicals can be absorbed through the respiratory tract, the 

skin, or the gastrointestinal tract. Understanding the effects of these compounds on the hearing of 

marine mammals is limited; however, hearing deficits have been established in cetaceans, 

including belugas, which were treated with aminoglycosides, a class of antibiotics known to be 

ototoxic (Finneran et al. 2005). When exposure to ototoxic chemicals is combined with exposure 

to noise, hearing loss is exacerbated by increasing both the breadth and severity of permanent 

threshold shifts; hearing loss can even occur at subtoxic chemical and sub-traumatic noise levels 

when neither exposure to the chemical nor noise would cause hearing loss in isolation (Steyger 

2009). The synergistic effect of noise and organic solvents is more serious after repeated 

exposure at lower levels (Steyger 2009).

The synergistic effect between certain chemical pollutants and noise is of increasing concern 

in the marine environment, especially in coastal areas where chemical pollutants are 

concentrated. Well-known chemicals that, when combined with excessive noise exposure, can 

have synergistic effects on hearing in humans include organic solvents (e.g., paint, adhesive 

solvents, or fuel fumes), some insecticides, heavy metals like lead and mercury, and some 

clinical drugs known to impact hearing (e.g., aminoglycoside antibiotics). It has been shown that 

the physiological impact can exponentially increase if the individual is concurrently or 

sequentially exposed to these chemicals and noise. For example, loud noise and solvent 

inhalation by dockyard workers has proven to generate a hearing deficit five times stronger than 

the one generated just by the loud noise exposure (Sliwinska-Kowalska et al. 2004). Jet fuel 

vapor inhalation and jet noise exposure led to permanent hearing loss in laboratory rats; 

however, when rats were exposed to the same concentration of jet fuel but not exposed to noise, 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-9

no effects on hearing were detected (Fechter et al. 2007). To our knowledge, these synergistic 

effects have not yet been described in marine mammals. However, the fact that CI beluga habitat 

is surrounded by many human activities that generate chemicals known to impact hearing (e.g., 

jet fuel from the airplane activity around the Inlet) and the fact that CI beluga habitat is noisy, 

raises the concern of potential synergistic effects on CI belugas from chemicals in the water and 

noise.

Another example of synergistic effects of multiple stressors is the toxicity among various 

contaminants that augment each other, whereas individual exposure to the same concentrations 

of those contaminants may yield little to no detectable effect (De Guise et al. 1998). There are 

well-documented examples of multiple stressors in terrestrial species that individually have little 

impact, but, when combined, can have major, negative, synergistic impacts that may cause death. 

For example, two studies (Relyea and Mills 2001; Relyea 2003) reviewed in Sih et al. (2004) 

found that several species of North American tadpoles exposed to the common pesticide carbaryl 

at a concentration only one-third of the recommended level suffered 10% mortality. However, 

when only the smell of a predatory newt was added, tadpole mortality increased to 80%, 

meaning that the introduction of the predator’s smell somehow increased the lethality of carbaryl 

eightfold. This synergistic effect was even more pronounced with bullfrog tadpoles: carbaryl 

alone caused only 2% mortality (indistinguishable from carbaryl-free controls), but when 

combined with the smell of predatory newts caused 92% mortality, a 46-fold amplification. This 

work showed that adding the stressor (the perceived risk of predation) to sublethal concentrations 

of carbaryl unexpectedly increased tadpole mortality, and the drastic increase in mortality did not 

require that actual predation take place.

In Chester Creek, a stream draining urban areas in Anchorage and directly discharging into 

Cook Inlet, the pesticide carbaryl was detected in high concentrations. This broad-spectrum 

insecticide, widely used throughout the Cook Inlet Basin to control spruce bark beetles, was 

detected in 79% of the samples from this creek (Glass et al. 2004) with concentrations as great as 

0.33 μg/L. Fifteen percent of the samples had carbaryl levels that exceeded drinking water 

standards and Canadian guidelines (Canadian Council of Ministers of the Environment, 2009) 

for the protection of freshwater aquatic life (0.2 μg/L). Therefore, CI belugas in upper Cook Inlet 

near Chester Creek, and potentially in other streams with urban and residential watersheds, could 

be exposed to high levels of carbaryl. Since contaminants (e.g., the pesticide carbaryl) and 

predators (e.g., transient killer whales) may co-occur in the preferred beluga habitat, a potential 

for synergistic effects may exist, if, like in the case of the tadpoles, the contaminants make the

exposed belugas more susceptible to predation. We note, however, that a direct comparison 

cannot be made between tadpoles and belugas, and we do not have information about the level of 

exposure to, or absorption of, carbaryl by CI belugas. Nevertheless, these studies underscore the 

possibility that CI belugas might be at risk from the negative synergistic effects as a result of coexposure to anthropogenic noise, widespread pollutants, and the presence of transient killer 

whales (e.g., detecting their presence acoustically without the need of actual physical 

encounters).

Climate change can also amplify the effects of some contaminants as climate-driven changes 

in temperature, pH, and salinity can alter contaminant toxicity and bioavailability (Schiedek et al. 

2007). For example, the half-life of the pesticide malathion increases substantially under a lower 

pH, suggesting increased persistence of this contaminant under expected conditions of climatedriven ocean acidification (Relyea 2004). Malathion serves here as an example of how 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-10

contaminant toxicity may change as the climate changes. There is no evidence to suggest that 

this pesticide, with low toxicity for mammals, short half-life in water (2–18 days), and low level 

of use in Alaska, is a threat to CI belugas.

b. Relative Concern

Predicting cumulative effects is extraordinarily difficult, as it requires knowledge of a myriad 

of contextual factors for each exposure (e.g., acoustic exposure; contaminant exposure; predatory 

exposure), and synergistic effects can be very unpredictable (Wright et al. 2007). Because 

susceptibility varies among individuals in a population and because mortalities may be dispersed 

over time, factors contributing to cumulative effects are difficult to detect, making mitigation of 

these effects challenging. Stressors related to the current small population size of CI belugas, 

when combined with anticipated trends of increased anthropogenic impacts, can increase the 

likelihood of co-occurring and interacting multiple stressors that may combine effects to the 

detriment of the CI belugas’ recovery.

Moreover, stress resulting from anthropogenic noise, a threat of high relative concern, needs

to be evaluated in combination with other stressors because noise has been demonstrated as a 

component of harmful synergistic effects in several animals and humans (Steyger 2009).

Given the increase of human activities in Cook Inlet and the presence of contaminants in 

Cook Inlet and CI belugas, the trend for and likelihood of cumulative effects is increasing over 

time. Cumulative effects are categorized as a threat of high relative concern for CI belugas due to 

the following: 1) multiple stressors occur year-round and throughout range of CI belugas; 2)

uncertainty regarding the magnitude of future cumulative effects; 3) uncertainty over the 

mechanisms of existing and future cumulative effects (including synergistic effects, if any); 4) 

difficulty in detecting impacts attributable to cumulative mechanisms; and 5) difficulty in 

effectively mitigating cumulative effects due to the occurrence of multiple stressors.

3. Threat Type: Noise

Anthropogenic noise effects to CI beluga prey are discussed in the “Threat Type: Reduction 

in Prey” section (III.A.6); and cumulative effects involving noise are considered in the “Threat 

Type: Cumulative Effects of Multiple Stressors” section (III.A.2).

a. Sources of Noise in Cook Inlet

The acoustic environment of Cook Inlet is naturally noisy, complex, and dynamic. Natural 

sources of noise are particularly abundant in the CI beluga hearing range and include: bottom 

substrate being transported by high currents; sand and mud bars generating breaking waves 

during low tide/high current periods; river mouths becoming rapids at low tide periods; and fast 

and pancake ice being formed during winter months and under continuous mechanical stress by 

high tide oscillations and currents. Furthermore, the inflow of cold freshwater of glacial origin 

can vary considerably near major river mouths and arms in the upper Inlet, creating a complex 

sound propagation environment due to changes in both salinity and temperature as a result of 

sharp water mass fronts. These differences in water density and temperature act as sound 

barriers, reflecting and refracting sound energy. In addition, the large volume of fresh water from 

glacial areas surrounding Cook Inlet introduces suspended glacial silt and sediments into beluga 

habitat. Silt and other fine sediments suspended in the water column create acoustic clutter (a 

volume of scattered sound reflection) that can further impede echolocation performance. The 
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Recovery Plan A. Discussion of Threat Types

III-11

presence of all of these natural sources of noise varies over time and space, as does their 

contribution to the overall ambient noise of Cook Inlet. Their contribution is important as a wide 

range of frequencies overlap with beluga signals, including both lower frequency ranges used for 

social communication and higher frequency ranges used for echolocation. The effects of these 

natural conditions, while difficult to quantify, may compromise CI beluga acoustic 

communication and echolocation, particularly as the sound transmission distance increases. 

Consequently, the natural acoustic space for CI belugas may be more limited than for belugas 

found elsewhere. This particular condition enhances the potential for negative effects when 

anthropogenic sources of noise are introduced into CI beluga habitat.

Due to the co-occurrence of Alaska’s urban center and the current range of CI belugas, a 

wide variety of anthropogenic noises that could affect recovery exists, especially in the upper 

Inlet. Most sources of anthropogenic noise in Cook Inlet are seasonal and occur during the icefree months, although some sources are present year-round. Sources of anthropogenic noise in 

Cook Inlet include: propeller cavitation, engines, and depth sounders associated with vessels; 

dredging activities; pile driving activities; military detonations; aircraft; airguns used for seismic 

surveys; drilling associated with oil and gas exploration; hydraulic/mechanical noise; and sounds 

associated with other noise-producing activities. Although there are several technical reports 

documenting specific Cook Inlet noise sources and their signal characteristics,

19 a 

comprehensive survey of anthropogenic noise sources in Cook Inlet and beluga exposure to these 

sources has not been conducted. Most of the identified sources in the Inlet are not well 

documented, and many are not controlled, monitored, or regulated. 

Due to industrial activity and development in the current range of CI beluga, a wide variety 

of anthropogenic noise sources that could potentially interfere with recovery are present in CI 

beluga habitat. Sources are listed below by order of importance, based on signal characteristics 

and the spatio-temporal (space and time) acoustic footprint. The order was determined by 

considering the following factors: intensity (loudness), frequency (range of tones), and duration 

of acoustic signal; area affected by the sound source; and duration of sounds in both seasonal 

terms (e.g., happening all summer) and frequency of occurrence (e.g., happening once per week 

throughout the summer; M. Castellote, NMFS, unpub. data).

• Tug boat noise: propeller cavitation (the formation of bubbles in a liquid) and engine 

noise including azimuth/bow thruster noise;

• Cargo/tanker noise: propeller cavitation and engine noise including bow thruster noise;

• Small vessel noise: outboard and inboard engine noise and propeller cavitation;

• Dredging: suction and/or grabbing operations;

• Pile driving noise: hammering or vibratory noise (rotatory or oscillatory to a lesser 

extent);

 

19 See a sample listing of acoustic reports pertaining to Cook Inlet and Cook Inlet belugas available on the NMFS AKR Research 

on Cook Inlet Belugas webpage: http://alaskafisheries.noaa.gov/pr/beluga-research-cook-inlet.
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• Military detonations of high explosives:

20 demolition and projectile explosions in military 

firing ranges;

• Oil/gas exploration: airgun sources for seismic survey and high power active transducers 

(multibeam echosounders, sub-bottom profilers, etc.);

• Shore construction noise: other than pile driving;

• Oil/gas exploitation: platform noise (in-air noise radiated into the water), drilling noise 

(in water and/or bottom substrate), air/water vessels during operations;

• Commercial jet aircraft: overflights, take offs, and landing approaches;

• Military jet aircraft: overflights, take offs, and landing approaches;

• Propeller aircraft: overflights, take offs, and landing approaches;

• Depth sounders: from vessels;

• Fishing related noise (other than engine noise): hydraulic/mechanical operations;

• Research related noise: sonars such as acoustic Doppler current profilers and dualfrequency imaging sonars; scientific echo sounders and other active transducers, boat 

transit for photo-identification surveys, and instrument deployment/retrievals, etc.; and

• Pipe and cable laying operations.

Climate change is having an indirect effect on ocean noise pollution (Reeder and Chiu 2010). 

As levels of carbon dioxide rise in the atmosphere, ocean waters are becoming more acidic. 

Ocean acidification reduces concentrations of seawater salts that absorb sound, particularly lowfrequency sound. This ocean pH change is predicted to be greatest in higher latitudes, allowing 

lower frequency sound to carry farther and to be stronger at a given distance. Shallow sound 

channeling exists in Cook Inlet, which allows potential noise impacts to be concentrated in 

shallow waters and become more spatially extensive (i.e., sound channels can trap noise and 

allow it to travel farther). At the same time, climate change may directly result in either an 

increase or decrease of in-water noise. For example, warming temperatures may reduce the 

prevalence of ice cover, and thus reduce ice-associated noise, but warmer temperatures may also 

result in higher wind speeds resulting in higher noise levels at the waters’ surface.

b. Potential Effects of Noise on CI Belugas

There is an extensive body of literature regarding the effect of anthropogenic noise on marine 

mammal behavior. Most of the studies addressing this problem have used behavioral attributes 

such as changes in site fidelity, dive patterns, swimming speed, orientation of travel, herd 

cohesiveness, and dive synchrony to indicate possible disturbance or stress caused by noise 

(Richardson et al. 1995). A review and summary of available information regarding effects from 

anthropogenic noise to beluga hearing and behavior is presented in Appendix IX.E – CI Beluga 

Hearing, Vocalization, and Noise Supplement.

 

20 Demolition activities and mortar/artillery firing on military ranges.
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Studies on belugas have revealed that anthropogenic noises have the possibility to cause 

threshold shifts in beluga hearing capabilities (e.g., Finneran et al. 2000, 2002a; Schlundt et al. 

2000); to mask the ability of animals to hear and decipher specific sounds (e.g., Erbe et al. 1999; 

Erbe 2000); to result in belugas altering their vocal behaviors (e.g., Lesage et al. 1999; Sheifele 

et al. 2005); or to result in displacement of animals from habitats (e.g., Finley et al. 1990; 

Richardson et al. 1997; Harris et al. 2007).

c. Relative Concern

Anthropogenic noise, particularly the combined effect of different sound sources occurring 

simultaneously or consecutively, has the potential to affect beluga acoustic perception, 

communication, echolocation, and behavior (such as foraging and movement patterns). 

Behavioral effects include processes of sensitization (increased response following repeated 

exposure) or habituation (decreased response following repeated exposure) and physiological 

processes related to hearing and stress. In the long term, anthropogenic noise may induce chronic 

effects altering the health of individual CI belugas, which in turn have consequences at the 

population level (i.e., decreased survival and reproduction). Although the effects on CI belugas

of the diverse types of anthropogenic noises occurring in their habitat have not been analyzed 

and are currently unknown, there is enough evidence from other odontocete species (and for 

some effects in other beluga populations) to conclude that the potential for a negative impact to 

CI beluga recovery is of high relative concern.

4. Threat Type: Disease Agents

a. Sources and Types of Disease Agents in Cook Inlet

A number of potential sources of disease-causing agents exist in and around Cook Inlet. 

Disease agents may include pathogens (such as bacteria, viruses, and fungi), parasites, and

harmful algal blooms (HABs). Belugas may be exposed to disease agents through: interactions 

with, or proximity to, other infected belugas or other species; ingestion of contaminated material 

or organism; open wounds; or inhalation. Natural sources of disease include other belugas, other 

wild animals, and environmental and water-borne pathogens of natural origin. Anthropogenic 

sources of disease include untreated sewage outfalls; malfunctioning septic systems; pet waste;

runoff from agricultural operations; and discharge from vessels (URS Corp. 2011). No 

comprehensive survey of disease sources or their characteristics are available. Transfer of 

disease and parasites between belugas and other wild or domestic species are poorly understood, 

and endemic disease and parasite loads of CI belugas in comparison to other populations are 

unknown. For an in-depth review of available information on this topic, see Appendix IX.H –

Cause of Death Analysis.

b. Relative Concern

Diseases have the potential to compromise health, reduce reproductive potential, and increase 

the chance of mortality. Diseases can have population-level effects throughout a species range. 

Although disease outbreaks among CI belugas are currently expected to be intermittent, climate 

change and increased pollution could cause an increase in disease frequency. In 2011, 62% of CI 

belugas photographically identified in Eagle Bay had signs of some level of current or previous 

infection (McGuire et al. 2014c).
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The necropsy record of stranded CI beluga carcasses shows only low levels of parasitism, 

and parasites that were present did not appear to have a significant negative impact (i.e., were not 

attributed to be the cause of death). Additionally, parasites most likely would only have a 

detrimental effect to the individual whale, and not result in population-wide effects. Thus, based 

on the available data, the threat of parasites to CI belugas currently appears to be of low relative 

concern.

Although HABs have the potential to detrimentally impact a large portion of the population, 

the reported incidence of HABs in Cook Inlet, and Alaska in general, has been very low 

(RaLonde 2001; Alaska Sea Grant 2012). However, LeFefebvre et al (2016) reported evidence 

that HAB toxins (e.g., domoic acid and saxitoxin) are present throughout Alaska waters at levels 

high enough to be detected in marine mammals. The authors concluded that current climate 

trends may result in conditions favorable to the growth of HABs, increasing the health risks to 

northern marine mammals. Burek-Huntington et al. (2015) found that domoic acid was present in 

very low levels in two of 17 CI belugas tested, and saxitoxin was present at just above detection 

level in one out of 15 CI belugas tested. In the one case where HABs were detected in a fetus, 

they were not detected in the mother, (Burek-Huntington 2015), suggesting that there may be a 

greater threat to CI beluga calves than adults. In addition to potential increases in the prevalence 

of HABs in Alaska, climate change is rapidly altering the global movement of pathogens, 

bringing diseases to new areas. Guimarães et al. (2007) modeled the dynamics of an infectious 

disease spreading through a reproductively isolated group of killer whales in the Pacific 

Northwest. That study’s results indicated that small populations, such as the CI beluga 

population, are susceptible to population-wide disease outbreaks. 

Currently, the incidence of disease as a factor in the deaths of CI belugas appears to be low, 

and there is little evidence to suggest diseases of concern are present in other mammals in the 

area. We assume some unknown level of disease is present in CI belugas, with a medium to high 

probability that disease will occur in the future. Moreover, a population-wide outbreak of a novel 

(new) disease could be catastrophic to the CI beluga population. As such, despite a low relative 

concern from parasites and a low incidence of disease currently, the threat to CI beluga recovery 

due to increases in HABs or a disease outbreak associated with novel pathogens in the future is 

of medium relative concern, and the overall relative concern for the impact of disease agents is 

medium.

5. Threat Type: Habitat Loss or Degradation 

This section does not include habitat loss or degradation from reduction of prey, pollution, or 

noise, which are discussed individually in other sections.

a. Sources of Habitat Loss or Degradation in Cook Inlet

In contrast to most beluga populations, which are observed seasonally in estuarine habitats, 

belugas in Cook Inlet are year-round residents (NMFS 2008a). With the CI beluga population 

decline in the mid-1990s, the spatial distribution of CI belugas in the summer contracted such 

that whales are primarily found in the upper portion of Cook Inlet (Rugh et al. 2010). Range 

contraction proportionate to population decline is consistent with the theory that populations tend 

to concentrate in areas of optimal habitat during periods of low abundance and expand outside 

those areas during increased abundance (MacCall 1990). Upper Cook Inlet would thus represent 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-15

preferred habitat, with the suitability of that habitat depending on both biotic and abiotic 

characteristics.

Ecological changes such as increased water temperature, siltation, and salinity changes due to 

changing volumes of freshwater runoff may occur over the long-term in response to climate

change. Such changes may also occur due to episodic events such as earthquakes or volcanic 

eruptions. Anthropogenic activities can result in substantial changes in habitat, or temporary or 

permanent loss of habitat. Such activities include in-water construction, port expansion, highway 

and bridge construction, culvert placement, changes in freshwater inflow from dams, dredging,

and channeling (NMFS 2008a). Seasonal anthropogenic activities that disturb the substrate can 

re-suspend sediments and chemicals and also degrade the acoustic propagation characteristics of 

the habitat, whereas continuous activities, such as sewage outfalls, can alter the chemical 

composition, prevalence of pathogens, or temperature of the habitat, particularly in the 

immediate environment of the outfall. Permanent structures, such as docks, platforms, bridges, or 

trestles, alter localized water flow and characteristics as long as the structure exists. While losses 

of area from in-water fill may be quite visible, changes in benthic substrate and currents resulting 

from other types of human infrastructure are less obvious and may have significant impacts on 

available prey. 

b. Relative Concern

While some habitat loss or degradation within the core range of CI belugas is evident, the 

population level effects of this degradation are unknown. Habitat impacts of past activities are 

poorly documented, and impacts of current and planned projects are not fully understood. 

Anthropogenic causes of habitat loss or degradation tend to be localized, seasonal, and 

increasing in frequency, whereas natural causes (e.g., warmer water temperatures under climate 

change scenarios) may operate range-wide.

All of these factors may limit suitable habitat either directly through whale disturbance (e.g., 

chemical impacts to skin tissue) and reduction of fitness, or indirectly through impacts to prey 

populations and reduced carrying capacity of the environment. Many of the anthropogenic 

activities affecting CI beluga critical habitat are concentrated in the coastal areas and are often 

seasonal. Anthropogenic activities in Cook Inlet are increasing, and there is a high probability 

there will be more habitat loss or degradation in the future. Moreover, the contraction of the 

range of CI belugas into the upper Inlet has resulted in increased proximity to the developed 

areas around Anchorage. However, most of the beluga habitat in Cook Inlet is not degraded to 

the point that adverse effects to CI belugas are apparent. The extreme tidal ranges, land use 

patterns, and bathymetry of much of Cook Inlet may make it unsuitable for many types of 

development activities. Even though the majority of Cook Inlet is undeveloped, the loss or 

degradation of habitat is of medium relative concern for CI belugas due to a limited 

understanding of how this habitat might be altered by various factors and the resilience of this 

habitat.

6. Threat Type: Reduction in Prey

Several factors may result in the reduction of the abundance, quality, availability, or 

seasonality of CI beluga prey. The impact of reduction of available prey on CI belugas is poorly 

understood, but may be the result of competition with humans or other animals. It may also result 

from habitat disturbances or modifications as a result of anthropogenic or natural factors.
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III-16

Factors, whether anthropogenic or natural, that affect the available prey species may have a 

greater impact on one prey species or species subcomponent (e.g., age or size-related). Resultant 

changes in relative abundance of prey will affect the prey composition available (Pyke et al. 

1977).

a. Competition for Prey Resources

CI belugas compete with humans and other animals for prey resources, particularly salmon 

and eulachon. Quantitative data on the spatial and temporal distribution of beluga prey in upper 

Cook Inlet are limited (see Appendix IX.F – CI Beluga Prey Supplement). Although 

management of fisheries targeting anadromous species in Alaska attempts to constrain harvests 

to be no greater than the level of surplus production, it is unlikely that escapement goals will be 

met in all tributaries across all years. Effects of fishing by humans on beluga foraging success 

are not well known, yet may include spatial and temporal components for any specific prey 

resource. Effects on belugas will depend on the extent to which a reduction occurs to the 

abundance, quality, or availability of prey (localized or Inlet-wide), and if the belugas can

compensate for losses of preferred prey by shifting to other feeding sites or less-preferred prey. If 

a non-preferred prey species is reduced, the relative or absolute abundance of preferred prey may 

increase over time, depending on the ecological linkages and response times. The temporal 

distribution of these prey resources may be as important as their magnitude, particularly for 

growing juveniles and pregnant and/or lactating female belugas. Changes in seasonality of prey 

may occur due to seasonality and species preference of fisheries, changes in seasonal fish habitat, 

or seasonal environmental changes affecting Cook Inlet. The extent to which shifts in the 

seasonality of prey species or temporal gaps in prey availability impact reproductive success and 

survival of belugas, particularly during critical life stages, is unknown. However, these impacts 

are likely to be most important if affecting temporal availability of energy-rich high-lipid prey.

Alternatively, events that result in decreases of specific runs or changes in the availability of prey 

(e.g., by changing schooling patterns or altering nearshore terrain) may leave temporal gaps in 

the availability of prey at sufficient densities resulting in the reduction in total days when beluga 

blubber fat storage can occur. For more information see Appendix IX.F – CI Beluga Prey 

Supplement.

CI belugas may also compete against other predators (harbor porpoise, harbor seals, killer 

whales, sea lions, large whales, sea otters, sea birds, etc.) for available prey resources, 

particularly in upper Cook Inlet where the available prey resources may be more limited in 

abundance or diversity. Although there may be some foraging specialization upon available prey 

species, there is also likely to be a high degree of dietary overlap due to the limited prey diversity 

available. In upper Cook Inlet, belugas are most likely to compete for prey resources with harbor 

seals and harbor porpoises, which have been documented also to be present in Cook Inlet year 

round and co-occur in the same general locations as CI belugas (Small et al. 2011; AEA 2013; T.

McGuire, LGL, unpub. data).

b. Disturbance or Modification of Prey Habitat

The amount or types of prey available to CI belugas may also be reduced as a result of 

disturbances or modifications to prey habitat. Anthropogenic activities that may detrimentally 

affect prey habitat and possibly reduce the availability of prey to belugas are present both 

seasonally and continuously in Cook Inlet. Anthropogenic activities in Cook Inlet that may 
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Recovery Plan A. Discussion of Threat Types

III-17

disturb or modify the habitat of beluga prey include dredging; oil or gas activities; hard rock 

quarrying; laying of electrical, communication, or fluid lines; construction of docks, bridges, 

breakwaters or other structures; and other activities. These activities may cause avoidance or 

destruction of an area used by beluga prey as a result of anthropogenic disturbance. Permanent 

structures, such as docks, platforms, or bridges, alter the Cook Inlet habitat by altering local tidal 

flow, among other potential effects. However, the net effect of anthropogenic structures on 

beluga prey remains unknown.

In addition to loss of habitat available to beluga prey species by displacement or avoidance, 

anthropogenic activities may reduce the quality of the prey as a result of contamination of the 

habitat. For example, mechanical disturbance of the seafloor (e.g., dredging) re-suspends silt, and 

potentially buried chemicals, into the water column. A sewer outfall plume alters both the abiotic 

and biotic environment, releasing various hormones, pharmaceuticals, and other chemicals into 

Cook Inlet. Catastrophic events such as oil or chemical spills are infrequent, but may have 

significant effects on beluga prey, whether through changes to spawning or migration patterns, 

direct mortality, or potential long-term sub-lethal impacts (Moles et al. 1994; Marty et al. 1997; 

Murphy et al. 1999). While some of these contaminants are known to bioaccumulate and be 

passed up the food chain, they also may impact the survival, quality, and reproduction of the 

prey species itself. For example, elevated copper concentrations can harm salmon and other CI 

beluga prey.

The habitat upon which beluga prey depend may also be affected by natural events, 

including: Pacific decadal oscillation, an El Niño-like pattern of Pacific climate variability

(potentially affecting rainfall, freshwater runoff, water temperature, and water column stability); 

climate change (potentially affecting glacial output and siltation and salinity in downstream 

estuarine environments); volcanic ash outfall (affecting siltation and water chemistry); and

earthquakes and associated landslides, elevation changes, and tsunami waves. Some of these

natural threats are infrequent, but may have instantaneous and substantial impacts upon 

abundance, quality, or seasonality of CI beluga prey. However, other threats, such as Pacific 

decadal oscillations, may occur more regularly, may or may not be readily detectable, may 

develop over an extended time period, and may have long-lasting ecological effects. 

Ecological regime shifts, in which species composition is restructured in association with 

abrupt changes in climate, have been identified in the North Pacific (Hollowed and Wooster 

1992; Anderson and Piatt 1999; Hare and Mantua 2000; Spies 2007) and are believed to have 

affected prey species availability in Cook Inlet. For example, in the 1970s, dominance in the 

Gulf of Alaska ecosystem transitioned from crustaceans to groundfish, particularly gadid (e.g., 

cods) species. In another analysis, Hare and Mantua (2000) reaffirmed the 1976 to 1977 

ecosystem change in the Gulf of Alaska and identified a less dramatic shift in 1989. Analyses of 

multi-decadal data from small-mesh trawl surveys conducted by NMFS and ADF&G showed 

ecosystem reorganization in the 1970s at Kachemak Bay in southern Cook Inlet and around 

Kodiak Island and in Shelikof Strait located in the northern Gulf of Alaska south and west of 

Cook Inlet Gulf waters (Bechtol 1997; Anderson and Piatt 1999). Of particular note was a 

decline in forage species, particularly pandalid shrimp and capelin, and increases in cod, pollock, 

and flatfish.

Changes to the marine, coastal, and freshwater ecosystems are known to be occurring as a 

result of global climate change and the associated occurrence of shifts in temperature, oxygen 

content, ocean acidification, and other physical and chemical changes (Doney et al. 2012), and 
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Recovery Plan A. Discussion of Threat Types

III-18

are expected to continue and even increase with continued changes in the earth’s climate system 

(IPCC 2013). Climate-driven change in the environment could strongly influence CI beluga prey 

distribution and population size through changes in growth, survival, reproduction, and spawning 

distribution, but the possibilities are complex (e.g., Tillman and Siemann 2011; Hollowed et al. 

2013; Link et al. 2015; Sydeman et al. 2015).

c. Anthropogenic Noise Effects on CI Beluga Prey

Recent literature reviews on the effects of sound on fish (Popper and Hastings 2009) 

conclude that little is known about these effects and that it is not yet possible to extrapolate from 

one experiment to other signal parameters of the same noise, to other types of noise, to other 

effects, or to other species. Limited available scientific literature indicates that noise can evoke a 

variety of responses from fish. Pile driving can induce a startle response, an avoidance response, 

and can cause injury or death to fish close to the noise source (Caltrans 2001, Abbott and BingSawyer 2002, NMFS 2011, Halvorsen et al. 2011).

Some noises may evoke flight and avoidance response in juvenile salmon. Other studies have 

shown that the avoidance response is temporary. Salmon have been found to respond to low 

frequency sounds, but only at very short ranges (Chamberlin 1991). Carlson (1994), in a review 

of 40 years of studies concerning the use of underwater sound to deter salmonids from hazardous 

areas at hydroelectric dams and other facilities, concluded that salmonids were able to respond to 

low-frequency sound and to react to sound sources within a few feet of the source. He speculated 

that the reason that underwater sound had no effect on salmonids at distances greater than a few 

feet is because they react to water particle motion/acceleration, not sound pressures. Detectable 

particle motion is produced within very short distances of a sound source, although sound 

pressure waves travel farther (USDOT 2005). It is likely that fish will avoid sound sources 

within ranges that may be harmful (McCauley et al. 2003).

Of all known CI beluga prey species, only coho salmon have been studied for effects of 

exposure to pile driving noise (Casper et al. 2012, Halvorsen et al. 2012). These studies defined 

very high noise level exposures (210 dB re 1μPa2.s) as threshold for onset of injury, and 

supported the hypothesis that one or two mild injuries resulting from pile driving exposure at 

these or higher levels are unlikely to affect the survival of the exposed animals, at least in a 

laboratory environment. Hart Crowser Inc. et al. (2009) studied the effects on juvenile coho 

salmon from pile driving of sheet piles at the Port of Anchorage in Knik Arm of Cook Inlet. The 

fish were exposed in-situ (in that location) to noise from vibratory or impact pile driving at 

distances ranging from less than 1 meter to over 30 meters. The results of this studied showed no 

mortality of any of the test fish within 48 hours of exposure to the pile driving activities, and for 

the necropsied fish, no effects or injuries were observed as a result of the noise exposure.

The effects of noise on other CI beluga prey species, such as eulachon, gadids, and flounder 

species is unknown.

d. Relative Concern

While the potential exists for human fishing pressure to change the abundance, seasonality, 

or composition of beluga prey, for targeted species, fisheries are managed with in-season 

reductions or closures if those fish stocks appear to be weak. However, not all fish stocks are 

assessed, and it is unknown whether management of fisheries for optimal returns provides 

sufficient densities in beluga feeding areas for efficient foraging by belugas. In addition, a 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-19

fishery would not be reduced or closed if escapement goals are met. But if the escapement goal 

arrived in a shorter time period (e.g., 30 days instead of 90 days), the benefit of optimal returns 

to CI beluga energetics may be very different.

It is likely there is interspecific competition for limited prey resources between CI belugas 

and other predators in Cook Inlet (e.g., harbor seal, harbor porpoise). However, the impact of this 

competition on the availability of prey to CI belugas has not been determined.

Habitat modification may result in changes in prey species availability and/or species 

composition throughout the range of CI belugas. While potentially having substantial effects on 

local ecosystems, natural threats are difficult to predict and mitigate. Many changes are tied to 

infrequent, short-term, uncontrollable events such as earthquakes or volcanic eruptions. Habitat 

disturbances may cause beluga prey to avoid an area, reduce viability of prey species, or interfere 

with belugas’ predation success. Anthropogenic noise may also have negative effects upon CI 

beluga prey. Noise impacts on fish may range from temporary displacement to barotrauma 

induced death (Popper and Hastings 2009). Moreover, as noted in Section III.A.3 (Threat Type: 

Noise), anthropogenic noise may affect beluga foraging performance.

Depending on the source, prey reduction can be a local or rangewide event, with a variable 

frequency of occurrence. While reduction of prey may result in reduced carrying capacity of the 

environment or reduce the fitness of CI belugas, the magnitude of the impact of a reduction of 

prey on CI belugas is unknown, as is the trend and future probability. As such, the threat to CI 

beluga recovery due to the reduction of prey is of medium relative concern.

7. Threat Type: Unauthorized Take 

In certain instances, NMFS may authorize or permit directed or incidental “takes”21 of CI 

belugas under the MMPA and ESA. “Directed take” occurs when an activity is intentionally 

harassing or harming the animals, such as occurs when conducting research on those animals; 

“incidental take” occurs when an activity results in harassment or harm to animals that were not 

the intended target of an activity, such as may occur when a construction activity introduces loud 

noises into the water. As part of ESA section 7 consultations, NMFS reviews and considers the 

effects of these types of requested takes on CI belugas to ensure authorization of these takes are 

not likely to jeopardize the continued existence of CI belugas or result in adverse modification of 

their critical habitat. In recent years, due to the precarious nature of the CI beluga population, no 

lethal takes have been authorized. NMFS has authorized a limited number of directed research 

projects, but the majority of the take authorizations have been for incidental take that would 

result in harassment only. Given that extensive reviews of the proposed activities’ effects to CI 

belugas are conducted prior to issuing take authorizations, these authorized takes are not 

considered to be a threat to CI belugas.

Activities which result in harassment or harm to CI belugas but which NMFS has not 

authorized (i.e., unauthorized take) may result in changes in CI beluga behavior, displacement of 

 

21 “Take” is defined by the MMPA as “to harass, hunt, capture, or kill or attempt to harass, hunt, capture, or kill any marine 

mammal” (16 U.S.C. § 1362(13)). The listing of a species as endangered makes it illegal to “take” (“to harass, harm, pursue, 

hunt, shoot, wound, kill, trap, capture, collect, or to attempt to engage in any such conduct”; 16 U.S.C. § 1532(19)) that 

species under the ESA, with certain exceptions (16 U.S.C. § 1538). Similar prohibitions are usually extended to threatened 

species.
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-20

CI belugas from important areas, or injury or mortality to CI belugas. Some activities with 

potential to result in unauthorized take or trauma include entanglements from fisheries 

operations, strikes from vessel activities, unanticipated mortalities or harassment associated with

research projects, mortalities or injuries from poaching and intentional harassment, and other 

adverse outcomes (e.g., displacement) associated with miscellaneous activities such whale 

watching. 

a. Sources of Unauthorized Take

Entanglements: Prior to the mid-1980s, the only reports of fatal takes of belugas incidental 

to fishing activities in Cook Inlet are from the literature (Murray and Fay 1979; Burns and 

Seaman 1986). While there have been sporadic reports since the mid-1980s of single beluga 

becoming entangled in fishing nets, the only known mortality associated with entanglement in a 

fishing net was the young CI beluga carcass recovered from a subsistence set net in 2012. 

Overall, the current rate of direct mortality from fisheries in Cook Inlet appears to be 

insignificant. There have been reports of non-lethal entanglement of CI belugas. For example, in 

2005, a CI beluga entangled in an unknown object, perhaps a tire rim or a culvert liner, was 

photographed in Eagle Bay (McGuire et al. 2013), and another CI beluga was repeatedly 

photographed 2010–2013 with what appeared to be a rope entangled around the upper portion of 

its body near the pectoral flippers (McGuire et al. 2014a, 2014b). It is not known if these animals 

were able to disentangle themselves or if they died as a result of the entanglements.

Strikes: Most of Cook Inlet is navigable and used by various classes of water craft that pose 

the threat of striking belugas. Presently, there are no restrictions on vessel speed limits, areas in 

which vessels may operate, or on the type or horsepower of vessels allowed in the upper Inlet.

There is compelling evidence that reduced vessel speed decreases the probability of vessel 

collision with large whales, such as the North Atlantic right whale (e.g., Laist et al. 2014).

However, smaller boats that travel at high speed and change direction frequently may present a 

greater strike threat for CI belugas. NMFS researchers have witnessed avoidance and overt 

behavioral reactions by CI belugas when approached by small vessels (e.g., Lerczak et al. 2000).

While ship strikes have not been a confirmed source of CI beluga mortality, a CI beluga washed 

ashore dead in September 2007 with “wide, blunt trauma along the right side of the thorax” that 

could be the result of ship strike trauma. In October 2012, a necropsy of another CI beluga 

carcass indicated the most likely cause of death was “blunt trauma such as would occur with a strike 

with the hull of the boat” (NMFS AKR, unpub. data). Scarring consistent with propeller injuries 

has also been documented among CI belugas (Burek 1999; LGL 2009; McGuire et al. 2011).

Further scar analysis would be required to estimate vessel size, and it would be difficult to 

determine whether the scars resulted from commercial, private, or research vessel interactions. 

Research: Research activities conducted in Cook Inlet have the potential to take CI belugas. 

Research activities not targeting belugas, such as research activities studying CI beluga prey or 

habitat, may incidentally harass CI belugas. If these research projects are not authorized by 

NMFS, and harass or harm CI belugas, these are unauthorized takes. Directed CI beluga research 

activities also have the potential to harass or harm CI belugas. NMFS has authorized take 

associated with several CI beluga research projects over the years. Such activities have included 

captures, tagging activities, biopsy activities, and aerial and boat-based activities. While certain 

invasive and non-invasive research activities targeting CI belugas are authorized by NMFS, none 

of the authorizations since the ESA-listing have allowed for mortality. Since 2003, the only 
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Recovery Plan A. Discussion of Threat Types

III-21

research effort involving contact with the whales was an effort to apply acoustic recorders to the 

whales via suction cup tags. The limited amount of invasive research efforts in recent years is 

due in part to the probability that three CI belugas died (an unanticipated outcome) as a result of 

a capture and satellite tagging research project in 2002. Photo-identification studies have 

identified and tracked seven individual belugas with scars attributable to the satellite tags; five of 

these whales were re-sighted in 2011 providing evidence that at least five whales survived a

minimum of nine years after tagging (McGuire et al. 2013). With the exception of the suction 

cup acoustic recorders and a biopsy feasibility project in 2016, which collected six small tissue 

samples from CI belugas, all research activities on CI belugas since 2003 have involved noninvasive techniques (e.g., passive acoustic recordings; aerial, boat, and land-based observations; 

photographic studies) with a low potential to adversely affect CI belugas. 

Poaching or intentional harassment: Cook Inlet is bordered by the densest human 

population in Alaska. This juxtaposition of people and belugas in and near coastal waters 

heightens the potential for illegal hunting, poaching, or intentional harassment (e.g., chasing 

whales with vessels). Much of the information on illegal harassment is based on data from 

beach-cast carcasses and anecdotal reports, which may underestimate illegal harassment due to 

lack of timely access to carcasses. Photographs of scars present on living CI belugas suggest that 

some injuries may be the result of illegal hunting (McGuire et al. 2011). However, there have 

been no reported fresh wounds or mortalities of CI belugas associated with firearms since the 

harvest was regulated in 1999; NMFS has documentation of only two potential gunshot victims 

(one in 1995 and one in 1998; NMFS AKR, unpub. data). Some scars have been speculated to be 

healed bullet wounds or possible harpoon marks (McGuire et al. 2011), however, photoidentification studies since 2005 have not documented fresh injuries suspected to be the result of 

illegal hunting or harassment (T. McGuire, pers. comm., LGL, unpub. data). There is little 

information available to suggest illegal hunting or harassment is currently occurring, perhaps in 

part due to increased awareness of the status of CI belugas and the prohibitions against hunting, 

shooting, or harassing the whales. The NOAA Office of Law Enforcement patrols Cook Inlet and 

investigates any reports of illegal hunting or harassment of CI belugas. As of September 2016, 

no poaching incidents have been confirmed, and there has been one civil conviction of 

harassment.

Other: Other activities also have the potential to take CI belugas. For instance, although there 

is currently no commercial whale watching industry for CI belugas, there are numerous small 

planes, boats, and other small watercraft (e.g., jet skis, kayaks, and wind and kite surfboards) in 

the Cook Inlet area which have been observed approaching CI belugas for closer viewing. These 

close approaches can result in CI belugas changing their behavior or leaving an important area in 

an effort to escape the harassment caused by the close approaches. 

b. Relative Concern

Unauthorized takes (i.e., those without NMFS authorization) have the potential to harass, 

disturb, displace, injure, or kill CI belugas. The activities of greatest concern to the recovery 

potential of CI belugas are those with the potential to injure or kill a CI beluga. Activities with 

the potential to result in unauthorized takes can be found rangewide in Cook Inlet, with certain 

localized hotspots. These activities are primarily seasonal, but given demographic and economic 

trends, the number of these activities in Cook Inlet is likely increasing in frequency. However, an 

increase in activities that could result in unauthorized take may not be a reliable indicator of an 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-22

increase in unauthorized takes. The frequency of occurrence of unauthorized takes is unknown. 

There is a medium probability that unauthorized take will occur in the future, but the magnitude 

of the impact to CI belugas is likely to be variable. If the effect is displacement or a short-term 

change in behavior, the magnitude of the threat on CI belugas is low, but if the effect is a 

mortality, then the magnitude is high. However, there is little information to definitively 

conclude mortalities are associated with unauthorized takes. More information is available to 

suggest injuries may be a notable concern, but photographic data of healed scars suggest some

injuries are not life threatening. Therefore, the overall relative concern of the impact of 

unauthorized takes is considered to be medium. 

8. Threat Type: Pollution

Pollution is the introduction of contaminants into the environment that causes adverse 

change. For the purpose of this review, pollution is synonymous with acute and chronic events 

that release notable/reportable quantities of chemicals or substances into the environment. 

Exposure to industrial chemicals as well as to natural substances released into the marine 

environment is a potential health threat for CI belugas and their prey. For an in-depth review of 

available information on this topic, see Appendix IX.G – CI Beluga Pollution and Contaminants 

Supplement.

a. Sources and Types of Pollution in Cook Inlet

A number of sources of chemical and biological pollution have been identified in and around 

Cook Inlet, but a comprehensive water quality survey of Cook Inlet is not available. Potential 

sources of pollution which could affect CI belugas include: offshore oil and gas development; 

municipal waste and bilge discharge; marine oil spills; runoff from roads, airport, military sites, 

mines, construction sites, and farms; terrestrial and marine spills of contaminants other than oil; 

resuspension of contaminants through dredging; ship ballast discharge; watercraft exhaust and 

effluent; coal transportation and burning; auto exhaust; antifouling paint; and trash.

Possible contaminants CI belugas could be exposed to include: persistent organic pollutants;

aromatic hydrocarbons; chlorinated hydrocarbons; heavy metals; endocrine disruptors;

pharmaceuticals; antibiotics; sanitizers; disinfectants; detergents; insecticides; fungicides; and 

de-icers. While NMFS has some data about levels of traditionally studied contaminants in CI 

belugas (e.g., Dichlorodiphenyltrichloroethane [DDT], polychlorinated biphenyls [PCBs], 

polycyclic aromatic hydrocarbons [PAHs], etc.), virtually nothing is known about other 

emerging pollutants of concern and their effects on CI belugas. The emerging pollutants of 

concern include endocrine disruptors (substances that interfere with the functions of hormones), 

pharmaceuticals, personal care products (chemicals such as soaps, fragrances, insect repellants, 

etc.), prions (infectious proteins that cause neurodegenerative disease), and other bacterial and 

viral agents that are found in wastewater and biosolids. 

URS (2010) evaluated the level of potential concern (probable, possible, unlikely) to CI 

belugas from various classes of chemicals. Chemicals identified by URS (2010) to be of 

probable and possible concern and for which at least some data are available for either CI 

belugas or other beluga populations are described in Table 8. URS (2010) categorized the 

following chemicals as unlikely to be of potential concern for CI belugas: hydrocarbons (other 

than PAH compounds), glycols, diagnostic agents, dietary supplements, personal care products, 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-23

engineered particles (<100 nanometers), or prions. Acute effects associated with oil spills and 

natural gas blowouts are considered in the threat type Catastrophic Events.

b. Relative Concern

Pollution occurs rangewide with localized hotspots throughout the CI belugas’ habitat, at 

variable frequencies depending on the source of the pollution. Point source pollution enters the 

water from a specific source (e.g., a sewage outfall pipe; in-water construction site; etc.); these 

sources of pollution may result in localized effects. Non-point sources of pollution in Cook Inlet 

occur over broader geographic areas that can ultimately have rangewide effects (e.g., runoff from 

roads, airports, agricultural sites, military training areas, etc.). Individually and collectively, point 

and non-point source pollutants may have either local or widespread effects, depending upon the 

location, size and abundance of the outfall sites, time of release, tidal conditions at the point(s) of

release, and characteristics of the pollutant(s). 

The amount of pollution entering Cook Inlet is likely increasing as the regional human 

population grows, a trend that is likely to continue. However, upgrading the Asplund Wastewater 

Treatment Facility, currently Alaska’s largest wastewater treatment facility, from a primary to a 

secondary treatment facility could make a notable difference in total pollutants released into 

Cook Inlet, particularly into Cook Inlet beluga whale critical habitat. The decision of whether to 

upgrade this facility is currently under review by the Environmental Protection Agency (EPA). 

Exposure to contaminants found in pollution may be the result of CI belugas’ direct contact 

with contaminants found in the water; inhalation of contaminants in the air; or ingestion of 

contaminants found in prey, mud, or silt. It is also possible that adult males may have higher

levels of contaminants stored in the body than do adult females because females may have the

ability to transfer some of their contaminant load to their calves during pregnancy and lactation.

There is little information on the potentially deleterious effects of contaminants on CI belugas; 

but it is likely that chronic exposure to contaminants may compromise an individual whale’s 

health, with the potential for population-level impacts.

For the contaminants that have been studied, CI belugas generally had lower contaminant

loads than did belugas from other populations (Becker et al. 2000, Lebeuf et al. 2004, NMFS 

2008a, Becker 2009, DFO 2012, Reiner et al. 2011, Wetzel et al. 2010, Hoguet et al. 2013). 

Based on these results, it is possible that the levels of pollution in Cook Inlet, the exposure to 

pollution by CI belugas, or the rate of uptake/retention of contaminants by CI belugas, is lower 

than that for other beluga populations. The more temperate habitat of CI belugas compared to 

belugas residing at higher latitudes may help explain why persistent organic pollutants are not as 

prevalent in whales living in Cook Inlet.22 Additionally, chemical analyses of water and dredging 

sediments from Cook Inlet found that contaminants analyzed were below management levels, 

and some were below detection limits (Frenzel 2002; U.S. Army Corps of Engineers [Corps] 

2003). 

The available information suggests that the magnitude of the pollution threat to CI belugas 

appears low, although not all pollutants to which these whales are exposed have been studied in 

 

22 Alaska Community Action on Toxins website accessed January 2, 2015: 

http://www.akaction.org/tackling_toxics/world/global_transport_toxics_arctic/.
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-24

Table 8. Compounds of probable and possible concern for CI belugas, for which data are available either for 

CI belugas or for other beluga populations.

Chemical Class Example Individual Constituents

Level of 

concern for CI 

Beluga

CI beluga 

data

Other 

beluga data

Chlorinated 

pesticides

Many banned in the U.S. in the 1970s, but are still 

used in other parts of the world: DDTs, aldrin, 

dieldrin, chlordane, endosulfan, mirex, toxaphene 

mixtures

Probable Yes Yes

Chlorinated 

dielectric fluids, 

transformer oils

Banned in the U.S. since the 1970s, but previously 

used as coolants and lubricants in transformers and 

other electrical equipment. 209 PCB congeners, 

aroclor mixtures

Probable Yes Yes

Chlorinated 

dibenzo-p-dioxins 

and furans 

Not intentionally used; byproduct emitted from 

waste incinerators, chlorinated bleaching, wood 

preservation, chemical synthesis. 75 Dioxin 

congeners (PCDDs), 135 furan congeners (PCDFs)

Probable No Yes

Metals Methyl mercury, selenium, butyltins, cadmium, 

arsenica

, leada, manganesea, mercurya, organic tina

Probable Yes Yes

Aryl and 

Polycyclic 

aromatic 

hydrocarbons 

(PAHs)

This is naturally occurring and also released from 

industrial products (asphalt, coal tar) and 

combustion of coal, oil, gas, wood, or organic waste. 

Of major concern are: Benzo(a)pyrene, anthracene, 

pyrene, toluenea

, benzenea, xylenea

Probable No Yes

Polybrominated 

flame retardants 

Commonly used as flame retardants in computers, 

textiles, construction, and electrical equipment. 

Polybrominated diphenylethers (PBDEs) (PBBs, 

polybrominated biphenyls are no longer produced in 

the U.S.)

Possible Yes Yes

Perfluorinated 

Compounds

Commonly used as a water and oil repellant, 

protective coatings in food packaging, textiles, and 

carpeting: Teflon coating, Perfluorooctane 

sulfonates, Perfluorooctanoic acid 

Possible Yes No

a Denotes compounds with known ototoxic (i.e., damaging to hearing) effects. 

Source: Modified and reproduced with permission from URS 2010, Table 5, and the factsheets.

this environment. Even though the existing studies are not comprehensive of all possible 

contaminants to which belugas may be exposed, the comparatively low levels of contaminants 

documented in CI belugas themselves as well as in the Cook Inlet water and sediment samples 

analyzed suggest that the relative concern of these known and tested contaminants to CI belugas 

is most likely low.

9. Threat Type: Predation

Predation may represent a continuing source of mortality for CI belugas. Predation rates may 

be a function of the size of the predator population and the availability of alternative prey, rather 

than the size of the prey (beluga) population. The frequency of predator induced mortality among 

belugas may also be influenced by anthropogenic factors, including climate change. 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-25

a. Predation by Killer Whales

Predation by killer whales has been identified as a source of mortality for CI belugas that 

may be independent of the size of the beluga population and may prove to be unsustainable for 

such a small population. While killer whales are regularly reported in lower Cook Inlet, the 

majority appear to be the resident (fish eating) type that would not prey on belugas (Matkin et al. 

2009). There have been no documented sightings of resident killer whales in upper Cook Inlet.

Transient (marine mammal-eating) killer whales are known to prey on CI belugas (Shelden et al. 

2003; NMFS, unpub. data), although rates of predation are uncertain and can only be estimated.

Based on the information available, 9–12 CI beluga mortalities since 1982 were suspected to be a 

direct result of killer whale predation (see Table 4). Over the past 25 years, predation of CI 

belugas by killer whales has not involved individuals in the catalog of transient killer whales 

identified from the Gulf of Alaska (including lower Cook Inlet) (C. Matkin, North Gulf Oceanic 

Society, unpub. data). It therefore appears that uncatalogued transient killer whales may prey on 

CI belugas.

A passive acoustic monitoring study examining the seasonal distribution of belugas

throughout Cook Inlet (Lammers et al. 2013) also detected the presence of killer whales. 

Between June 2009 and May 2010, the acoustic recorders detected killer whales 17 times. Most 

detections were at the Homer Spit location, with a single detection at both the Tuxedni Bay and 

Beluga River locations. Of these 17 killer whale detections, only the one recorded near the 

Beluga River in upper Cook Inlet was likely from a transient killer whale, which has an acoustic 

behavior very different and distinguishable from resident killer whales (Barrett-Lennard et al. 

1995). The killer whale detection off the Beluga River was concurrent with the presence of

belugas at that site. Despite relatively high levels of marine mammal observer effort, killer 

whales have been infrequently reported in upper Cook Inlet 

Based on the available data, it appears that only a small group of (uncatalogued) transient 

killer whales may occasionally prey on the belugas in upper Cook Inlet. It is not known whether 

there is a relationship between the rate of killer whale predation and the reduced size of the CI 

beluga population or the contraction in the range of CI belugas. The presence of killer whales in 

Cook Inlet may increase beluga live-stranding events, thus indirectly contributing to CI beluga 

mortality. However, the shallow, highly turbid, and restricted waters of the upper Inlet provide 

challenges to killer whales which may lead to killer whales stranding (e.g., killer whales stranded 

in Turnagain Arm in 1991, 1993, 2000, and 2002), and reduce the benefit of preying on belugas 

in that region. 

b. Predation by Sharks

Sharks have been postulated as a predator of CI belugas, but there is insufficient evidence at 

this time to consider them a serious threat. Shark predation attempts have been suspected, based 

upon observations of tooth-rake marks on some CI belugas (LGL 2009), but there is no 

conclusive evidence that shark predation occurs. Pacific sleeper and salmon sharks are found in 

the region, but it is unknown whether these sharks prey on or attack living cetaceans. However, 

as water temperatures in Cook Inlet rise with climate change, the incidence of sharks in Cook 

Inlet may increase (O’Brien et al. 2013).
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-26

c. Predation Effects on a Small Population (i.e., predator pit)

Predation rates of CI belugas may or may not be density dependent. However, at low 

population levels of prey, predator:prey relationships can create a predator pit. That is, the prey 

population may decrease to a level from which it cannot recover unless the predation pressure is 

reduced (Liermann and Hilborn 2001). Although belugas form only a small part of the transient 

killer whale diet, a numerically constant annual removal of belugas by killer whales from a small 

and declining beluga population would represent a threat that is inversely proportionate to the 

beluga population level. 

d. Relative Concern

As previously stated, there is no conclusive evidence that shark predation on CI belugas 

occurs. Killer whale predation on CI belugas appears to occur at fairly low levels, with only 10–

13 suspected CI beluga mortalities attributable to killer whales since 1982. There is no 

information to suggest the level of predation by killer whales has increased over time. Rather, 

killer whale predation appears to occur intermittently at very low levels (e.g., three suspected CI 

beluga mortalities in the past 17 years). In 2008, killer whale predation was identified as a 

“moderate” threat in the Conservation Plan for Cook Inlet Beluga Whales (NMFS 2008) when it 

was assumed there was an average of one killer whale-related mortality per year. However, from 

January 2008 through August 2016, there have only been two suspected predation-related 

mortalities, and one of these two beluga carcasses was in such poor condition that a definitive 

determination of a predation event was not possible. Killer whale sightings in upper Cook Inlet 

reported to NMFS have also been infrequent.

Predation is currently of low relative concern for the recovery of CI belugas, primarily 

because it occurs at such low levels, and has long been a part of CI beluga population dynamics.

However, any increase in predation removals in excess of one beluga per year from this small 

population could reduce or reverse the rate of recovery.

10. Threat Type: Subsistence Hunting

a. Legal Subsistence Hunting

Legal subsistence hunting of CI belugas by Alaska Natives is currently conservatively 

managed; no subsistence harvest has occurred after 2005. However, some past subsistence

hunting practices have had negative population level impacts on CI belugas, and the effects of 

these impacts likely persist. The dramatic decline in beluga abundance during the mid-1990s, 

and likely during the 1980s as well, corresponds to a time of unregulated subsistence hunting. 

These practices were a major contributor to the observed population decline (64 FR 56298, 

October 19, 1999; NMFS 2008b). This spike in subsistence harvest was largely attributed to 

participation by hunters from locations that had not traditionally harvested CI belugas.

Because the average CI beluga population estimate for 2007–2012 was below 350 whales, no 

subsistence hunting is authorized through 2017, as outlined in the final subsistence harvest 

regulations for these whales (73 FR 60976, October 15, 2008; NMFS 2008b). Per these 

regulations, the average CI beluga population abundance estimate from 2013–2017 will be 

reviewed in 2017 to determine if a legal hunt will be authorized for the five year period 2018–

2022. However, because CI belugas are an endangered species, NMFS will not authorize a hunt 

if it is determined that the activity is likely to jeopardize the continued existence of CI belugas. 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan A. Discussion of Threat Types

III-27

Only Alaska Natives are eligible for subsistence hunting, and in order to qualify for subsistence 

hunting of CI belugas, a valid co-management agreement with NMFS must be in place. Because 

CIMMC disbanded in 2012, NMFS does not have a co-management agreement with any Alaska 

Native organization specific to CI belugas. 

b. Relative Concern

In the past, subsistence hunts resulted in either injury or mortality to CI belugas. There were 

localized hotspots within Cook Inlet where most hunting occurred, seasonally or intermittently.

However, the last CI beluga taken as a result of subsistence hunting was in 2005. The current 

conservative management of legal subsistence hunting means no subsistence hunts will be 

considered until 2018, and will only be authorized if the associated mortality would not 

jeopardize the continued existence of the species (i.e., the magnitude of the effect to the 

population would be low). Therefore, there is no immediate threat to the CI beluga population or 

its recovery as a result of legal subsistence harvests, and the relative concern is low.
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Recovery Plan B. State of Alaska’s List of Threats

III-28

B. State of Alaska’s List of Threats to CI Belugas

The ADF&G uses Alaska’s Wildlife Action Plan (ADF&G 2006) to assess the needs of species 

with conservation concerns and to prioritize conservation actions and research. The “problems, 

issues, or concerns” for CI belugas listed in this plan closely resemble the list of threats 

identified above (Table 6), and are as follows: 

• Resource prey competition with people;

• Incidental mortality of belugas in fisheries (entanglements in nets, shooting);

• Potential impacts from pollution and contaminants that need monitoring:

o Oil and gas developments,

o Municipal waste and bilge discharge, and

o Marine oil spills;

• Subsistence harvests;

• Vessel interactions (recreational, commercial, high speed vessel);

• Anthropogenic noise (seismic testing, vessel traffic, drilling, dredging, industrial 

activities like pile driving, aircraft overflights);

• Predation by killer whales;

• Strandings;

• Potential impacts from environmental change;

• Loss of genetic diversity;

• Potential for ESA listing changing ability to manage, gather information, take action;

• Unknowns (age-specific survival and reproduction, parasites, diet, life history 

parameters); and

• Highly concentrated, clustered distribution increasing vulnerability (e.g., oil, spills, vessel 

traffic, harassment, etc.).
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan C. Section Summary

III-29

C. Section Summary: Threats to Recovery

At this time, it is unknown what factor(s) continue to limit growth and recovery of CI 

belugas. It may be that the cumulative effects of multiple stressors are impeding recovery,

whereas the effects of individual stressors in isolation would not impede recovery.

Ten potential threats are identified and assessed in this recovery plan, based on current 

knowledge of threat factors. Assessments were based on the information and data gaps presented 

in the plan’s Background section, as well as in the supplemental information presented in the 

appendices. Climate change, which has both natural and anthropogenic sources, is not addressed 

as a separate threat, but rather is discussed with respect to how it may affect other threats. Table

6 provides: 1) a listing of each threat discussed in this section; 2) a summary of the major effect 

of the threat on CI belugas; 3) a qualitative description of the threat’s extent, frequency, trend, 

probability, and magnitude; and 4) a qualitative rating of each threat’s relative concern for CI 

beluga recovery. 

The “problems, issues, or concerns” for CI belugas listed by the State of Alaska’s Wildlife 

Action Plan (2006) closely resemble the list of threats identified here.

Threat Type: Catastrophic Events

Several natural factors may result in a catastrophic event with potential to adversely affect CI 

belugas, including effects from environmental or climatic changes, earthquakes, volcanos, novel 

disease outbreaks, mass strandings resulting in large numbers of mortalities, and failures of key 

salmon runs. Anthropogenic activities, such as oil spills and natural gas blowouts, among others, 

may also result in a catastrophic event with detrimental effects on CI belugas. Catastrophic 

events may also have significant effects on CI beluga prey, whether through changes to 

spawning or migration patterns, direct mortality, or potential long-term sub-lethal impacts. A 

catastrophic event on its own may not always directly adversely affect CI belugas; rather, it may 

lead to a mass stranding event, which could have catastrophic results if there are multiple 

mortalities as a result of the stranding. Mortalities associated with a live stranding event do not 

appear to be common. Effects from catastrophic events are variable, and in addition to mortality, 

may also result in compromised health or injury to individual whales, reduced overall fitness or 

resilience of the population, or reduced carrying capacity of the environment; however, 

depending on the location of the event, the exposure or effect to CI belugas will vary. Small 

populations, such as the CI beluga population, may be more susceptible to adverse effects 

resulting from catastrophic events than large populations. The reduced summer range of CI 

belugas into the upper Inlet makes them far more vulnerable to catastrophic events that have the 

potential to kill or injure a significant portion of the population. It is expected that most 

catastrophic events would be localized events, affecting only a portion of the CI belugas’ range. 

Past experience indicates the frequency of catastrophic events in Cook Inlet is low. 

Anthropogenic activity in Cook Inlet is increasing, however, and environmental and climatic 

conditions are changing. Thus the probability of adverse effects resulting from a future 

catastrophic event is thought to be medium to high. The magnitude of effect upon CI belugas of a 

catastrophic event is a function of several factors, including type of event, location of event, and 

exposure of whales to the event. However, given the history of live stranding-related mortalities 

and given the fact that mortalities can have an immediate and notable impact to the recovery 

potential of the population, we ranked the magnitude of the effects of catastrophic events as 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan C. Section Summary

III-30

variable, but potentially high. We conclude the overall relative concern of the impact of 

catastrophic events on CI belugas is of high concern.

Threat Type: Cumulative Effects of Multiple Stressors

Multiple stressors occur continuously throughout the range of CI belugas. While it is difficult 

to quantify or characterize effects on CI belugas from individual stressors, it is even more 

difficult to characterize the potential cumulative effects from a combination of stressors. 

Exposure to any given stressor at a sub-lethal level may predispose individual belugas to greater 

susceptibility to mortality or long-term effects (for example, reproductive failure) from other 

stressors. Death can also result from different combinations and intensities of multiple stressors. 

Cumulative impacts have been a long-standing issue in the debate over noise effects on marine 

mammals; the additive effects of multiple noise sources, as well as the combination of noise and 

other stressors, are of particular concern. Perhaps most important are potential synergistic effects 

in which two stressors interact to cause greater harm than the sum of the effects of the stressors 

individually. For example, a stressor may increase cortisol levels, which in turn tends to reduce 

immune response. There are well-documented examples of multiple stressors in terrestrial 

species that individually have little impact, but, when combined, can have major, negative, 

synergistic impacts that may cause death. In the case of CI belugas, contaminants and predators 

(e.g., transient killer whales) may occur in the preferred habitat, creating a potential for 

synergistic effects if the contaminants make the belugas more susceptible to predation. CI 

belugas might be at risk from the negative synergistic effects from anthropogenic noise 

exposures coupled with other stressors such as widespread pollutants or the presence of transient 

killer whales (e.g., detecting their presence acoustically without the need of actual physical 

encounters). Accurate prediction of all the potential cumulative effects requires a reasonable 

knowledge of all the various contextual factors for each exposure and is therefore difficult. 

Stressors related to the current small population size of CI belugas, when combined with 

anticipated trends of increased anthropogenic impacts, can increase the likelihood of cooccurring and interacting multiple stressors, reducing the likelihood of population recovery in the 

near term. Of particular concern are the cumulative effects of multiple stressors (acoustic and 

non-acoustic), given the noisy environment of Cook Inlet. Given the growth of activities in Cook 

Inlet, the trend for cumulative effects is increasing over time, with a high probability that these 

effects will continue in the future. Uncertainty over the complexity of potential mechanisms and 

difficulty in detection of their impacts and their potential mitigation make the cumulative effects 

of multiple stressors a threat category of high relative concern regarding potential impediments 

to recovery of CI belugas.

Threat Type: Noise

The acoustic environment of Cook Inlet is naturally noisy, complex, and dynamic. Natural 

sources of noise are particularly abundant and loud in the CI belugas’ range and include: bottom 

substrate being transported by high currents; sand and mud bars generating breaking waves 

during low tide/high current periods; river mouths becoming rapids at low tide periods; and fast 

and pancake ice being formed during winter months and under continuous mechanical stress by 

high tide oscillations and currents. The effects of these natural conditions, while difficult to 

quantify, may compromise CI beluga acoustic communication and echolocation, particularly as 

the sound transmission distance increases. However, CI belugas have presumably adapted to 

accommodate such noise. The addition of anthropogenic noise, to which the whales have not 

necessarily adapted, may have negative effects. Due to the highly concentrated human 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan C. Section Summary

III-31

population in the current range of CI belugas, a wide variety of anthropogenic noise sources that 

may affect fitness are present in CI beluga habitat, especially in the upper Inlet. Most sources of 

anthropogenic noise in Cook Inlet are seasonal and occur during the ice-free months, although 

some sources are present year-round. Sources of anthropogenic noise in Cook Inlet include:

propeller cavitation, engines, sonar, dredging, pile driving, military detonations, aircraft, seismic 

air guns, drilling, geophysical and geotechnical equipment, and other mechanical noise. The 

effect of anthropogenic noise, particularly the combined effect of different sound sources 

occurring simultaneously or consecutively, has the potential to affect beluga acoustic perception, 

communication, echolocation, and behavior. In the long term, anthropogenic noise may induce 

chronic effects altering the health of individual CI belugas, which in turn have consequences at 

the population level (i.e., decreased survival and reproduction). Despite the fact that direct and 

indirect effects of these sounds on CI belugas have not been analyzed and are currently 

unknown, there is enough evidence from other odontocete species (including other beluga 

populations) to conclude that a high potential exists for negative impacts. Anthropogenic noise 

also has the potential to indirectly affect the survival and reproduction success of CI belugas by 

having negative effects on their prey. Depending on the source, a noise can be localized or occur 

rangewide. While noise may result in compromised communication and hearing of CI belugas 

and may contribute to habitat degradation, the magnitude of the impact of noise on CI belugas is 

unknown, but potentially high. There is a high probability that anthropogenic noise in Cook Inlet 

will continue and increase in the future, and given that the natural noise is already limiting, the 

threat to CI beluga recovery due to anthropogenic noise is of high relative concern.

Threat Type: Disease Agents (Pathogens, Parasites, Harmful Algal Blooms)

Potential sources of disease-causing agents exist in and around Cook Inlet. Disease agents 

may include pathogens (such as bacteria, viruses, and fungi), parasites, and harmful algal blooms 

(HABs). The necropsy record of stranded CI beluga carcasses shows only low levels of 

parasitism, and parasites that were present did not appear to have a significant negative impact 

(i.e., were not attributed to be the cause of death). Additionally, parasites most likely would only 

have detrimental effects at the scale of individual whales, with population-wide effects unlikely. 

Thus, the threat of parasites is currently of low relative concern for CI belugas. Although HABs 

have the potential to detrimentally impact a large portion of the population, the reported 

incidence of HABs in Cook Inlet has been very low to date. However, there is evidence that 

HAB toxins are present throughout Alaska waters at levels high enough to be detectable in 

marine mammals; moreover, current climate trends may result in conditions favorable to the 

growth of HABs, increasing the health risks to marine mammals. In addition to the potential 

prevalence of HABS, climate change is rapidly altering the global movement of pathogens, 

bringing diseases to new areas. Small populations, such as CI belugas, are susceptible to 

population-wide disease outbreaks. A population-wide outbreak of a novel (new) disease could 

be catastrophic to CI belugas. Based on the number of whales photographed in Eagle Bay in 

2011 with indications of past infection, we assume disease of some sort is present in the 

population at unknown levels, and recognize there is a medium to high probability that disease 

will increase in the future. Currently, the incidence of disease as a factor in the deaths of CI 

belugas appears to be low, and there is little evidence to suggest diseases of concern are present 

in other mammals in the area. As such, while current incidence of disease and parasitism is a low 

relative concern, the threat to CI beluga recovery due to increases in HABs or a disease outbreak 

associated with novel pathogens in the future is of medium relative concern, and the overall 

threat posed by disease agents is of medium relative concern. 
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan C. Section Summary

III-32

Threat Type: Habitat Loss or Degradation

Concurrent with the CI beluga population decline in the mid-1990s, the spatial distribution of 

CI belugas contracted such that whales are found primarily in the upper portion of Cook Inlet 

near Anchorage during the summer. Climate-driven increased water temperature, siltation, 

changes in volume of freshwater runoff, and reduced salinity may occur gradually. However, 

when they result from episodic events, such as earthquakes or volcanic eruptions, effects may be 

immediate. Examples of anthropogenic activities that can result in substantial changes in habitat, 

or temporary or permanent loss of habitat, may include in-water construction, port expansion, 

highway and bridge construction, dredging, changes in freshwater inflow from dams, and river 

dredging or channeling. These types of anthropogenic threats tend to be localized, seasonal, and 

increasing in frequency, whereas natural threats may operate range-wide at either unknown or 

increasing frequency (e.g., warmer water temperatures under climate change scenarios). Both 

natural and anthropogenic factors may limit suitable habitat either directly in the form of whale 

perturbation and reduction of fitness (e.g., chemical impacts to skin tissue), or indirectly through 

impacts to prey populations and reduced carrying capacity of the environment. Most of the 

anthropogenic activities disturbing CI beluga critical habitat are concentrated in the coastal zone 

and are often seasonal. Although most of the beluga habitat in Cook Inlet is not degraded to the 

point that adverse effects to CI belugas are apparent, anthropogenic activities in the Inlet are 

increasing, and there is a high probability there will be more habitat loss or degradation in the 

future. Concurrent with increasing anthropogenic activities in Cook Inlet, the trend of habitat 

loss or degradation for CI belugas is also increasing over time, and the contraction of their range

into the upper Inlet has resulted in increased proximity to the developed areas around Anchorage. 

Due to a limited understanding of how this habitat might be altered by various factors and its 

resilience to perturbations, the loss or degradation of habitat is of medium relative concern for CI 

belugas.

Threat Type: Reduction in Prey

The impact of reduction of available prey on CI belugas is poorly understood and may have 

several effect pathways including: changes in the total availability, quality, species composition, 

and seasonality of prey. While the potential exists for human fishing pressure to dramatically 

change the abundance, seasonality, or composition of beluga whale prey, for targeted species, 

fisheries in Alaska are managed with in-season reductions or closures if those fish stocks appear 

to be weak. However, not all fish stocks are assessed, and it is unknown whether management of 

fisheries for optimal returns provides sufficient densities in beluga feeding areas for efficient 

foraging by belugas. It is likely there is interspecific competition for limited prey resources 

between CI belugas and other predators in Cook Inlet (e.g., harbor seal, harbor porpoise). Habitat 

modification may result in changes in species availability and/or species composition throughout 

the range distribution of CI belugas. Depending on the source, a reduction of prey can be a 

localized event or occur Inlet-wide, with a variable frequency of occurrence. While reduction of 

prey may result in reduced carrying capacity of CI beluga habitat or reduce CI beluga fitness, the 

magnitude of the impact of a reduction of prey on CI belugas is unknown, as is the trend and 

future probability. As such, the threat to CI beluga recovery due to the reduction of prey is of 

medium relative concern.
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan C. Section Summary

III-33

Threat Type: Unauthorized Take

In certain instances, NMFS may authorize or permit directed or incidental “takes” of CI 

belugas under the MMPA and ESA. These authorizations undergo extensive reviews prior to 

issuance. Authorized takes are not considered to be a population-level threat to CI belugas. 

Activities which result in harassment or harm to CI belugas but which NMFS has not authorized 

(i.e., unauthorized take) may result in changes in CI beluga behavior, displacement of CI belugas 

from important areas, or injury or mortality to CI belugas. Some activities with potential to result 

in unauthorized take include entanglements from fisheries operations, strikes from vessel 

activities, unanticipated harassment or mortalities from research activities, mortalities or injuries 

from poaching and intentional harassment, and other adverse outcomes (e.g., displacement) 

associated with miscellaneous activities such as whale watching. 

While there have been sporadic reports over the years of individual belugas becoming 

entangled in fishing nets, the only known fishery-related mortality in recent years was one

yearling CI beluga carcass recovered in 2012 from a set net. Ship strikes have not been 

confirmed in a CI beluga death, but there are two instances where death by ship strike was highly 

probable given the blunt trauma sustained by the whales. Scarring consistent with non-lethal 

propeller injuries has also been documented in the CI beluga photo-identification catalog.

Research activities not targeting belugas, such as research activities studying CI beluga prey 

or habitat, may incidentally harass CI belugas, and if not authorized by NMFS, these are 

unauthorized takes. NMFS has authorized take associated with several directed CI beluga 

research projects over the years, including capture, tagging, biopsies, and aerial and boat-based 

surveys, but recent authorizations have not allowed for mortality. It is possible that three CI 

belugas died (an unanticipated outcome) as a result of a capture and satellite tagging research 

project in 2002. With the exception of an effort to apply acoustic recorders to the whales via 

suction cup tags and a biopsy feasibility project, all other directed research activities have 

involved non-invasive techniques (e.g., passive acoustic recordings; aerial, boat, and land-based 

observations; photographic studies) with a low potential to adversely affect CI belugas. 

There is little information available to suggest illegal hunting or harassment is currently 

occurring, perhaps in part due to increased awareness of the status of CI belugas and the 

prohibitions against hunting, shooting, or harassing the whales. The lack of reports to NMFS 

regarding illegal hunting attempts; the near absence of conviction by the NOAA Office of Law 

Enforcement for suspected cases of illegal hunting and harassment; the lack of mortalities 

associated with firearms for over 15 years; and the lack of fresh injuries documented through 

photo-identification studies leads to a conclusion that the threat of illegal hunting or harassment 

has decreased in recent years, and currently occurs at levels at or near zero. There is a medium 

probability that unauthorized takes will occur to some degree in the future, but the magnitude of 

the impact to CI belugas is variable, depending upon the effect. If the effect is displacement or a 

short-term change in behavior, the magnitude of the threat on CI belugas population is low, but if 

the effect is mortality, then the magnitude is high. The overall relative concern of the impact of 

unauthorized takes resulting from activities such as fisheries, vessel operations, research, whale 

watching, and other miscellaneous activities is medium.
Cook Inlet Beluga Whale III. THREATS TO RECOVERY

Recovery Plan C. Section Summary

III-34

Threat Type: Pollution

CI belugas may be exposed to contaminants through direct contact in the water; inhalation of 

contaminants in the air; or ingestion of contaminants found in prey, mud, or silt. Pollution often 

enters the water from a specific source (e.g., a sewage outfall pipe; in-water construction site; 

etc.); these sources of pollution may result in localized effects. Other sources of pollution in 

Cook Inlet occur over broader geographic areas and can ultimately have rangewide effects (e.g., 

runoff from roads, airports, agricultural sites, military training areas; etc.). Thus, depending on 

the source of the pollution, the extent of the effect may be either localized or rangewide, with a 

variable frequency of occurrence. Given the increases in the human population and development 

of Cook Inlet, it is likely that the level of pollution entering Cook Inlet is increasing and will 

continue to increase in the future. However, if the Asplund Wastewater Treatment Facility, 

Alaska’s largest wastewater treatment facility, is upgraded in the future from a primary treatment 

facility to a secondary treatment facility the overall pollution entering Cook Inlet could stabilize 

or decline in the near term. It is possible that CI belugas have been chronically exposed to low 

levels of contaminants in Cook Inlet for some time. For the contaminants that have been studied, 

CI belugas have generally had lower contaminant levels than did belugas from other populations, 

and thus the magnitude of the threat to CI belugas from pollution is assumed to be low. Even 

though the available data do not include assessment of all possible contaminants to which 

belugas may be exposed, the comparatively low levels of contaminants documented in CI 

belugas, as well as in Cook Inlet waters and sediments analyzed, suggest that known and tested 

contaminants are in general of low relative concern.

Threat Type: Predation

Transient (mammal eating) killer whales are known to prey on CI belugas, however, there 

have only been 9–12 CI beluga mortalities since 1982 suspected to be a direct result of killer 

whale predation. In addition to directly reducing CI beluga abundance via mortality, the presence 

of killer whales in Cook Inlet may increase beluga live-stranding events. It appears that only a 

small group of transient killer whales may occasionally prey seasonally on the belugas in upper 

Cook Inlet. Killer whale sightings in upper Cook Inlet reported to NMFS have been infrequent.

The shallow, highly turbid, and restricted waters of the upper Inlet may lead to killer whales 

stranding, and may reduce the benefit of preying on belugas in that region. Although predation 

on CI belugas by sharks has been postulated, there is no conclusive evidence that shark predation 

on CI belugas occurs. There is a medium probability that a low level of predation by sharks will 

occur at some point in the future, but if the trend remains stable, the magnitude of the effect upon

CI belugas is low. Overall, predation is currently of low relative concern for the recovery of CI 

belugas.

Threat Type: Subsistence Hunting

In the 1990s, legal subsistence hunting of CI belugas by Alaska Natives had a direct negative 

impact on belugas in Cook Inlet; however, subsistence hunting is currently conservatively 

managed, and no harvests are authorized through 2017. Harvests after 2017 will only be 

considered if specific population size parameters are met and if it is determined that allowing a 

mortality will not jeopardize the continued existence of CI belugas. As such, there is no 

immediate threat to CI belugas or their recovery as a result of legal subsistence harvests, and the 

relative concern from subsistence hunting is low.
Cook Inlet Beluga Whale IV. RECOVERY STRATEGY

Recovery Plan

IV-1

IV.RECOVERY STRATEGY 

We know the CI beluga population is not recovering as expected after the regulation of 

subsistence hunting in 1999, but we do not know why. Before that can be determined, more 

information must be obtained about basic CI beluga biology and effects of potential threats on CI 

belugas.

This complex situation requires a comprehensive, integrated, adaptive recovery strategy. This 

strategy consists of data acquisition (on CI beluga biology, life history, ecology, and 

anthropogenic activities), integration of data sets from multiple sources, and application of these 

results to management (e.g., development and implementation of mitigation to avoid or reduce 

adverse effects), with continuous feedback between research and management actions.

In light of the recent decline, small population size, life history characteristics, and increasing 

number and magnitude of potential threats, it is challenging to identify the most expedient way to 

achieve recovery of CI belugas. We recognize that recovery will not occur immediately and will 

require a prolonged effort that is capable of adapting as new information becomes available, 

threats are mitigated or new threats arise, or the status of the CI beluga population changes. 

Thus, we structured this plan to emphasize addressing the most critical elements as a means to 

first curb the population decline and stabilize the population, then incorporate adaptive 

management reviews and revisions in the future to work toward population growth and recovery. 

Given the lack of clear reasons for the failure to recover following the regulation of the 

subsistence harvest in 1999, a balance must be struck when allocating scarce resources in our 

efforts to bring about recovery of this species. In an effort to strike this balance, we assert that 

the most expedient way to achieve recovery is by first addressing those threats identified as of 

medium or high relative concern (see Table 6). Doing so is not meant to indicate threats of low 

relative concern are ruled out as threats, nor is it meant to preclude or discourage actions taken 

by NMFS or other entities to address threats initially identified as being of low relative concern.

Rather, if a choice has to be made between addressing a threat of high/medium relative concern 

or a threat of low relative concern, we recommend the resources be allocated to addressing the 

higher ranked threat.

The recovery criteria and recovery actions outlined in the following sections address the 

threats of medium or high relative concern, and do not discuss in detail threats of low relative 

concern. Nevertheless, to ensure the recovery plan remains strategic, a recovery action is 

included that calls for periodic reassessment of the threats considered of low relative concern to 

determine if the status of those threats has elevated to the point specified recovery actions need 

to be defined. Furthermore, by adopting an adaptive recovery strategy, NMFS does not intend to 

require a protracted, formal process for reclassifying the severity of individual threats to CI 

belugas prior to taking actions to address them. Rather, we will seek guidance from experts in 

how to best respond to new information that has implications upon the severity of threats to CI 

belugas, and we will endeavor to follow that guidance.

The actions in this recovery plan include research, management, monitoring, and 

education/outreach efforts that take a comprehensive approach to addressing CI beluga recovery.

Threats-based recovery actions attempt to improve our understanding of threats and the 

population-level consequences of threats; in addition, these recovery actions attempt to improve 

our ability to manage and eliminate or mitigate threats. 
Cook Inlet Beluga Whale IV. RECOVERY STRATEGY

Recovery Plan

IV-2

Recognizing the importance of keeping the public apprised of the status and outcome of the 

recovery actions, the recovery strategy also identifies a multi-faceted education and outreach 

action. In addition to addressing the threats, we recognize the importance of continuously 

monitoring the CI beluga population, and have therefore included recovery actions specific to 

population monitoring goals.

To summarize, the strategy of this recovery plan is to:

• Continue to monitor the status of the CI beluga population and improve the 

understanding of CI beluga biology;

• Improve the understanding of the effects of threats of medium or high relative concern on 

CI belugas;

• Improve the management of threats of medium or high relative concern to reduce or 

eliminate the effect of those threats on CI belugas;

• Periodically reassess whether the relative concern of each potential threat identified in 

this plan has changed over time;

• Integrate research findings into current and future management actions; and

• Keep the public informed and educated about the status of CI belugas, the threats limiting 

their recovery, and how the public can help achieve recovery of these whales.
Cook Inlet Beluga Whale V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA

Recovery Plan C. Recovery Criteria

V-1

V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA

Section 4(f)(1)(B) of the ESA requires that each recovery plan contain objective, measurable 

criteria which, when met, would result in a determination that the species be delisted.

A. Recovery Goals

The ultimate goal of this plan is to achieve the recovery of CI belugas to a level sufficient to 

warrant their removal from the List of Endangered and Threatened Wildlife and Plants under the 

ESA (delist). The intermediate goal is to reclassify CI belugas from endangered to threatened

(downlist). To downlist CI belugas from endangered to threatened, NMFS must determine that 

the population is no longer “in danger of extinction throughout all or a significant portion of its 

range” (16 U.S.C. § 1532(6)). To delist CI belugas, NMFS must further determine that the 

population is not “likely to become an endangered species within the foreseeable future

throughout all or a significant portion of its range” (16 U.S.C. § 1532(20)). These determinations 

include consideration of the population’s abundance and demographic parameters, taken together 

with threats as identified under the ESA section 4(a)(1) factors considered for listing.

B. Recovery Objectives

When considering the listing of a species, five statutory factors (see Section I.B. History of 

the Listing Status of Belugas in Cook Inlet) are analyzed. These same factors must be considered 

in downlisting and delisting, with objectives related to each factor included as part of the 

recovery criteria. The following recovery objectives were identified for CI belugas and linked to 

the five listing factors:

• Ensure adequate habitat exists to support a recovered population of CI belugas. Habitat 

needs include sufficient quantity, quality, and accessibility of prey species (Listing Factor 

A);

• Ensure that commercial, recreational, scientific, or educational activities are not 

inhibiting the recovery of CI belugas (Listing Factor B);

• Ensure that the effects of diseases and disease agents on CI beluga reproduction and 

survival are not limiting the recovery of the CI beluga population (Listing Factor C);

• Ensure that regulatory mechanisms other than the ESA are adequate to manage threats to 

the sustainability of CI belugas (Listing Factor D); and

• Continue monitoring the population to identify and mitigate any new natural or manmade 

factors affecting the recovery of CI belugas (Listing Factor E).

C. Recovery Criteria

Section 4(f)(1) of the ESA requires recovery plans to incorporate “objective, measurable 

criteria which, when met, would result in a determination...that the species be removed from the 

list” (16 U.S.C. § 1533(f)). For many species, these criteria have focused primarily on a 

population size, trend, or some other demographic factor, but neglected to address the threats that 

resulted in the need to list the species. This recovery plan contains both demographic criteria and 

threats-based criteria for downlisting and delisting. All the demographic and threats-based 

criteria listed below must be met in order for CI belugas to be considered “recovered”; however, 

only the downlisting criteria must be met for consideration for reclassification from 

“endangered” to “threatened” (Table 9). The threats-based downlisting and delisting criteria 
Cook Inlet Beluga Whale V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA

Recovery Plan C. Recovery Criteria

V-2

below are organized according to the five ESA section 4(a)(1) factors (labeled A-E, 

respectively).

We note that recovery under the ESA is an iterative process with periodic analyses to provide 

feedback into the species’ status and progress towards recovery. The ESA requires a review of 

the status of each listed species at least once every five years. Periodic review of the species may 

lead to updates or revisions to the recovery plan, changes in the listing status of the species, or 

delisting. While meeting all of the recovery criteria would indicate that the species should be 

delisted, it is possible that delisting could occur without meeting all of the recovery criteria if the 

best available information indicated that the species no longer met the definition of endangered 

or threatened. Changes to the species’ status and delisting would be made through rulemaking 

after considering the same five ESA factors considered in listing decisions, taking new 

information into account.

1. Downlisting Criteria for Reclassifying CI Belugas from “Endangered” to “Threatened”

CI belugas may be considered for reclassifying from endangered to threatened (i.e., downlisted) 

when all of the following demographic and threats-based criteria have been met. The threatsbased recovery criteria are designed to evaluate the five ESA section 4(a)(1) factors and are 

organized accordingly (labeled A–E). There are no downlisting criteria identified for Listing 

Factor C (disease or predation) because we concluded that if the threats under the other listing 

factors are ameliorated and the population has achieved the demographic criterion for 

downlisting, then CI belugas will have made sufficient progress toward recovery such that 

reclassification from endangered to threatened may be considered (however, with respect to 

delisting, a recovery criterion for Listing Factor C is described below).

a. Downlisting Demographic Criterion

1. The abundance estimate for CI belugas is greater than or equal to 520 individuals, and there 

is a 95% or greater probability that the most recent 25-year population abundance trend 

(where 25 years represents one full generation) is positive. 

Justification: For long-term sustainability, a recovering population must show adequate 

population size and positive population growth over a timeframe that is long enough to 

encompass expected environmental variability. In the absence of better information, NMFS 

considers the historical abundance estimate of 1,300 whales to be the best estimate of the 

carrying capacity of CI belugas. We have no data at this time to indicate whether this carrying 

capacity may have changed. The threshold of 520 whales (40% of carrying capacity) represents

the approximate mid-point between the lowest reported abundance estimate for CI belugas (278 

belugas; 21% of carrying capacity) and the abundance level at which delisting may be considered 

(780 belugas; 60% carrying capacity); in addition, it is a level at which the population should not 

be considered in danger of extinction, assuming there is also statistical confidence the population 

has exhibited positive growth over the previous generation (previous 25 years) and threats have 

been adequately addressed. A 25-year timeframe was selected for population growth because it is 

a biologically-based time period that is expected to reasonably encompass environmental 

variability affecting the population. We chose the 95% probability level for a positive population 

trend because this level would provide a widely accepted degree of confidence that the 

population trend is positive. We recognize there is variability around survey point estimates, and 

a single population point estimate may over- or under-estimate the true population size. Survey 
Cook Inlet Beluga Whale V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA

Recovery Plan C. Recovery Criteria

V-3

variance should be taken into consideration as the population size approaches 520 to help ensure 

that consideration of downlisting is not based on anomalous conditions and accounts for the 

population trend over a full generation. The longer a population sustains a positive growth rate, 

the more confident we can be that the population is likely to continue to grow and become stable 

in the future and is resilient to stochastic events.

b. Downlisting Threats-Based Criteria

Listing Factor A: The Present or Threatened Destruction, Modification, or Curtailment of its 

Habitat or Range

Objective: Measures are in place to evaluate and ensure adequate habitat exists to support a 

recovered population of CI belugas. Habitat needs include sufficient quantity, quality, and 

accessibility of prey species to support a stable or growing population at the identified 

demographic criterion level.

A.1 Ninety-five percent of CI belugas sampled within the most recent 25 years are 

determined by cetacean experts to display no signs of poor nutrition, indicating a very 

high degree of confidence that nutrition is not limiting CI beluga recovery.

A.2 Sufficient prey are available to, at a minimum, sustain CI belugas at the identified

demographic criterion level. This determination shall take into consideration belugas’ 

energetic requirements, accounting for variances due to age, sex, and reproductive status, 

and the specific prey available to CI belugas. Absent information specific to CI belugas, 

estimates of the energetic requirements of belugas in other wild populations or belugas in 

captivity may be used as proxy values in this determination.

Listing Factor B: Overutilization for Commercial, Recreational, Scientific, or Educational 

Purposes 

Objective: Ensure that commercial, recreational, scientific, or educational activities are not 

inhibiting the recovery of CI belugas. 

B.1 All research activities in Cook Inlet that may affect CI belugas implement protocols that 

avoid reductions in the population’s recovery rate.

Listing Factor C: Disease or Predation

Objective: Ensure that the effects of diseases and disease agents on CI beluga reproduction and 

survival are not limiting the recovery of the CI beluga population.

If the threats under the other listing factors are ameliorated and the population has achieved the 

demographic criterion, then no recovery criteria would be necessary for this listing factor to 

consider reclassification of CI belugas from endangered to threatened (however, with respect to 

delisting, a recovery criterion for this listing factor is described below).

Listing Factor D: The Inadequacy of Existing Regulatory Mechanisms 

Objective: Ensure that regulatory mechanisms other than the ESA are adequate to manage threats 

to the sustainability of CI belugas.

D.1 Cook Inlet fisheries management programs account for the energetic needs of CI belugas

and allow for adequate available prey to sustain a recovering population (i.e., accounting

for beluga prey availability as opposed to focusing solely on prey escapement goals). 
Cook Inlet Beluga Whale V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA

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V-4

D.2 Oil and hazardous substance spill prevention and response plans specifically address 

protections for CI belugas.

D.3 Subsistence harvest is managed in accordance with the Final Rule for the Taking of Cook 

Inlet Alaska Beluga Whale Stock by Alaska Natives (73 FR 60976, October 15, 2008),

and the harvest is managed to ensure that it does not cause a measurable reduction in the 

rate of CI beluga recovery.

D.4 Management actions address cumulative effects, as they become known, in a way that 

promotes recovery of CI belugas.

D.5 CI beluga foraging and reproductive habitats (e.g., calving, nursing) are protected 

through appropriate management measures (e.g., time and area closures) to ensure the 

integrity of these habitats for meeting the needs of a growing CI beluga population.

D.6 Management actions address and reduce the effects of anthropogenic noise on CI belugas 

and their habitat.

Listing Factor E: Other Natural or Manmade Factors Affecting its Continued Existence

Objective: Continue monitoring the population to identify and mitigate any new natural or 

manmade factors affecting the recovery of CI belugas. 

E.1 A comprehensive stranding response program for CI belugas: 1) is implemented in 

partnership with the CI beluga stranding network members; 2) promotes faster 

notification of, and responses to, all CI beluga strandings (dead or live); 3) establishes 

robust protocols for responding to live strandings and/or tracking belugas after a live 

stranding event; 4) collects data to determine cause of death (e.g., disease, injury, 

predations, auditory damage, etc.); and 5) includes annual meetings or drills to review 

and practice stranding response protocols. 

2. Delisting Criteria for Considering CI Belugas “Recovered”

CI belugas may be considered for “delisting” and hence, recovered (i.e., no longer classified as 

an endangered or threatened species) when, in addition to meeting the downlisting criteria above, 

the following demographic and threats-based delisting criteria are also met. The threats-based 

recovery criteria are designed to evaluate the five ESA section 4(a)(1) factors and thus are

organized accordingly (labeled A–E).

a. Delisting Demographic Criteria 

1. The abundance estimate for CI belugas is greater than or equal to 780 individuals, and there 

is a 95% or greater probability that the most recent 25-year population abundance trend 

(where 25 years represents one full generation) is positive.

Justification: For management purposes, NMFS considers the historical abundance estimate of 

1,300 whales to be the best estimate of the carrying capacity of CI belugas. We have no data at 

this time to indicate whether this carrying capacity may have changed. The threshold of 780 CI 

belugas (60% of carrying capacity) is the approximate mid-point between the lowest reported 

abundance estimate for CI belugas (278 belugas; 21% of carrying capacity) and the estimated 

carrying capacity of 1,300 whales; in addition, it is a level at which the population would be 

considered unlikely to become endangered within the foreseeable future within all or a 

significant portion of its range, assuming the population has exhibited statistically significant 
Cook Inlet Beluga Whale V. RECOVERY GOALS, OBJECTIVES, AND CRITERIA

Recovery Plan C. Recovery Criteria

V-5

positive growth over the previous generation (previous 25 years) and threats have been

adequately addressed. This is also the population level at which NMFS would reconsider the 

depleted classification of CI belugas under the MMPA. A 25-year timeframe was selected for 

population growth because it is a biologically-based time period that is expected to reasonably 

encompass environmental variability affecting the population. We chose the 95% probability 

level for a positive population trend because this level would provide a widely accepted degree 

of confidence that the population trend is positive. We recognize there is variability around 

survey point estimates, and a single population point estimate may over- or under-estimate the 

true population size. Survey variance should be taken into consideration as the population size

approaches 780 to help ensure that consideration of delisting is not based on anomalous 

conditions and accounts for the population trend over a full generation. The longer a population 

sustains a positive growth rate, the more confident we can be that the population is likely to 

continue to grow and become stable in the future and is resilient to stochastic events.

b. Delisting Threats-Based Criteria 

Listing Factor A: The Present or Threatened Destruction, Modification, or Curtailment of its 

Habitat or Range

Objective: Ensure adequate habitat exists to support a recovered population of CI belugas. 

Habitat needs include sufficient availability (i.e., quantity, quality, and accessibility) of prey to 

sustain the population at the identified demographic criterion level. 

A.1 The quantity, quality, and accessibility of prey available to CI belugas are sufficient to 

sustain a recovered population for the foreseeable future (as determined, for example, by 

beluga-specific energetics models and projections of prey availability in Cook Inlet). 

A.2 The summer range of CI belugas has expanded so that 95% of CI belugas documented 

during comprehensive Inlet-wide summer aerial surveys are found within an area 

comparable to the area documented by Rugh et al. (2010) for the 95% distribution during 

the time period 1993–1997 (see Figure 7 in this plan). An expansion of the CI beluga 

summer range back to historic extent will reduce susceptibility of the entire population to 

most threats, and is a likely indicator of recovery. For this assessment, the CI belugas’ 

summer range should be determined using at least the most recent six-year time period, 

and based on at least three different years’ abundance surveys.

Listing Factor B: Overutilization for Commercial, Recreational, Scientific, or Educational 

Purposes 

Objective: Ensure that commercial, recreational, scientific, or educational activities are not 

inhibiting the recovery of CI belugas. 

B.1 The best available scientific data (e.g., via a population model or another scientifically 

rigorous assessment method) indicate that commercial, recreational, educational, or 

scientific activities are not having negative population-level effects on CI belugas and 

that the effects of these activities are not expected to result in a population decline postdelisting. 

Listing Factor C: Disease or Predation 

Objective: Ensure that the effects of diseases and disease agents on CI beluga reproduction and 

survival are not reducing the rate of recovery of the CI beluga population. 
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V-6

C.1 Known CI beluga deaths due to disease agents (e.g., pathogens, parasites, and HABs) 

during the most recent 10 years are sufficiently below CI beluga recruitment levels to 

allow for population growth, even when deaths due to other causes are included.

Listing Factor D: The Inadequacy of Existing Regulatory Mechanisms 

Objective: Ensure that regulatory mechanisms other than the ESA are adequate to manage threats 

to the sustainability of CI belugas.

D.1 A written agreement signed by NMFS and the State of Alaska is implemented which 

describes: how the State’s fishery management plans for Cook Inlet salmon and eulachon

are linked to goals for stock-specific spawning escapements that provide sustained yield 

for harvest and account for prey needed by belugas (and other ecosystem components), 

including quantity and temporal availability of prey; how such plans minimize the take of 

CI belugas pursuant to fishery activities in State waters of Cook Inlet; and how future 

actions taken by the State will comport with the MMPA. 

D.2 A cooperative program, which includes coordination among federal, state, tribal, and 

local authorities, is implemented with a goal of mitigating effects from human activities 

in Cook Inlet and with measures in place to ensure such human activities, especially 

those which are noise-producing, do not result in negative population-level effects on CI 

belugas.

Listing Factor E: Other Natural or Manmade Factors Affecting its Continued Existence

Objective: Continue monitoring the population to identify and mitigate any new natural or 

manmade factors affecting the recovery of CI belugas. 

E.1 A post-delisting monitoring plan for CI belugas is developed and approved prior to 

delisting. 

E.2 Analysis of information available about the effects of stranding-associated morbidity and 

mortalities and other non-anthropogenic threats determines that such threats are not

having negative population-level effects on CI belugas and that such threats are not 

expected to result in a population decline post-delisting.

E.3 Information available regarding cumulative effects of multiple stressors indicates that 

they are not having negative population-level effects on CI belugas and that they are not 

expected to result in a population decline post-delisting.
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Recovery Plan C. Recovery Criteria

V-7

Table 9. Criteria for considering reclassification (from endangered to threatened, or from threatened to not 

listed) for CI belugas.

Status Demographic criteria Threats-Based criteria

Reclassified from 

Endangered to 

Threatened

(i.e., downlisted)

The abundance estimate for CI belugas is 

greater than or equal to 520 individuals,

and there is a 95% or greater probability 

that the most recent 25-year population 

abundance trend (where 25 years 

represents one full generation) is positive.

AND The 10 downlisting threats-based 

criteria are satisfied.

Reclassified to Recovered

(i.e., delisted) 

The abundance estimate for CI belugas is 

greater than or equal to 780 individuals,

and there is a 95% or greater probability 

that the most recent 25-year population 

abundance trend (where 25 years 

represents one full generation) is positive.

AND The 10 downlisting and 9 delisting 

threats-based criteria are satisfied
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Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan

VI-1

VI.RECOMMENDED RECOVERY ACTIONS

This section provides a listing of recommended research, management, monitoring, and 

education/outreach actions targeted at achieving recovery of CI belugas. These recommended 

actions are organized into two categories: 1) population monitoring, recovery plan 

implementation, and education/outreach actions; and 2) threats management actions. The 

population monitoring, recovery plan implementation, and education/outreach actions recognize 

the importance of continuing to monitor the population, not only to improve our understanding 

of the whales, but also as a means to determine if recovery of CI belugas is occurring. These 

actions are designed to allow for the implementation and oversight of recovery activities, as well

as for implementation of outreach activities to ensure that the public is informed of the status of 

threats, and actions taken, to reduce the effects of those threats to CI belugas. The threats 

management actions encompass actions aimed at assessing and managing the threats ranked as 

medium or high relative concern, and include actions that allow us to better understand the 

threats and their effects on CI belugas and to improve our ability to manage or mitigate the 

threats.

The narrative provided for each action is intended to provide guidance to resource managers, 

stakeholders, industry, researchers, and the public. These actions are intended to reduce or 

eliminate medium- and high-ranked threats and to recover CI belugas. These recommended 

actions are forward looking. They do not include those actions that NMFS or others have already 

implemented or are in the process of implementing, nor do they include tasks that address a 

threat of low relative concern.

NMFS intends for the recovery plan to be a dynamic document that may change over time 

based on the progress of recovery and the availability of new information. As new information is 

obtained, additional actions will be identified and incorporated into the plan. As is the case for all 

recovery plans under the ESA, NMFS will regularly review this plan and will assess the relative 

success of these actions in protecting CI belugas. Recovery actions may be changed, subtracted,

or added accordingly. We also recognize that implementing the recommended recovery actions 

listed in this section is not the only viable path forward and that actions not included in this plan 

may contribute to recovery of CI belugas. For example, there may be better methods for 

assessing if a particular threat is limiting recovery. In addition, we recognize that some research 

or monitoring actions may be dependent on continued funding, and may not be achieved if 

funding is unavailable. Actions intended to obtain the same information as actions contemplated 

in this plan should not be dismissed just because they are not included in this plan.

Any action which may harass or harm CI belugas, even if on this list, should first involve 

discussions with NMFS AKR staff to ensure the benefits to CI beluga recovery outweigh the 

potential costs to individual whales or the population. Actions which may result in any form of 

take to CI belugas must be authorized by NMFS in advance of the proposed implementation 

date.
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Recovery Plan A. Recovery Actions and Narrative

VI-2

A. Recovery Actions and Narrative

POPULATION MONITORING, RECOVERY PLAN IMPLEMENTATION, AND 

EDUCATION/OUTREACH ACTIONS:

1. Continue to conduct surveys to estimate abundance, and analyze population trends, calving 

rates, and distribution.

Non-invasive population monitoring surveys are vital to understanding the status of the 

species, the effects of threats, and the effectiveness of management and recovery actions. 

Therefore, such surveys should be continued into the future and expanded as appropriate. 

Two survey methods currently being used to monitor the population are aerial surveys and a 

photo-identification study of individual CI belugas. Aerial surveys of belugas conducted by 

NMFS are used to derive population estimates, a calf index, and distribution and movement 

patterns. Results provide a long-term record of population trend. Results of aerial surveys were 

used in the ESA listing decision, to determine critical habitat, and to determine whether the 

population has reached the numerical threshold required before subsistence hunting can legally 

resume. While conducting aerial surveys less than annually will result in reduced precision in the 

short term trend estimates, annual survey results may not be required to reliably detect changes 

in trends over greater than 10 years. Of particular value for population monitoring are synoptic23

distribution data that are not available by any other means for Cook Inlet. 

A photo-identification study of CI belugas has been ongoing since 2005. The photoidentification study has the potential to provide information about individual and population 

characteristics of CI belugas including survivorship, calving rates, maternal investment to calves, 

residency and movement patterns, and life history characteristics for many individually identified 

belugas, including mothers with calves.

2. Create and support a CI Beluga Recovery Coordinator position.

The biggest challenges in creating this recovery plan were: 1) a lack of information; and 2) 

identifying and accessing information that already existed. A full time, permanent Cook Inlet 

Beluga Recovery Coordinator based out of Anchorage, Alaska, would be an advocate for CI 

beluga recovery actions and serve as a central point of contact for all information and activities 

relevant to CI beluga recovery. We note that NMFS has on staff Recovery Coordinators for the 

Hawaiian monk seal, Steller sea lion, and Pacific salmon. NMFS currently has a staff person 

designated to coordinate CI beluga recovery, but that person also has other substantial duties.

The duties of the Cook Inlet Beluga Recovery Coordinator should include the following:

• Coordinate and support CI beluga research activities.

• Organize an annual late-winter CI beluga research workshop to:

o Review strandings and carcass data from the previous year;

o Review research results from the previous field seasons; and

 

23 Data obtained nearly simultaneously over a large area.
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

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VI-3

o Plan and coordinate future research for upcoming field seasons and for longer-term 

projects, with the goal of increasing collaboration among projects and information 

acquired.

• Coordinate management, monitoring, and mitigation activities (consultations, regulations, 

take allocations, and permits).

• Maintains a list of CI beluga takes associated with all anthropogenic activities (all 

authorized takes plus any known unauthorized takes).

• Create and maintain a CI beluga geospatial database with information from research 

projects, strandings, sightings, environmental data, prey data, and monitoring and 

mitigation efforts. Make data available to researchers, stakeholders, industry, and the 

public. Duties include archiving, managing, and disseminating information from multiple 

sources.

• Coordinate the CI beluga stranding network and stranding data.

• Develop sighting networks and educational outreach.

• Coordinate a community-based beluga and habitat monitoring program.

• Keep current on global beluga research (including captive animals) and update the CI 

beluga research and stakeholder community.

• Maintain and expand the current library of beluga related research papers, monitoring 

reports, gray literature (unpublished reports), conference posters, presentations, permits, 

and take allocations; these items should continue to be made available to the public on 

the NMFS AKR website.

• Improve communications and coordination among various NMFS offices - the 

Anchorage field office, the regional office in Juneau, AFSC MML, the national permit 

office, the national stranding program office, and the national recovery program office; 

improved communications with the MMC, ADF&G, and NGOs would also be a goal of 

this position.

3. Create and support a CI Beluga Recovery Implementation Task Force.

A CI beluga recovery implementation task force should work with and advise the Cook Inlet 

Beluga Recovery Coordinator. The group, led by the Coordinator, should meet annually to 

review recovery progress and to advise on implementation of recovery actions recommended by 

this recovery plan.

4. Increase efforts to identify and monitor individual CI belugas, coordinating photoidentification, stranding data, genetic studies, and body condition assessments via biopsy 

samples of skin and blubber.

Identifying and quantifying threats to CI belugas will require obtaining a great deal of 

information about the individual animals that remain. To maximize our ability to detect and 

quantify risks, we recommend that the existing individual CI beluga photo-identification 

database that is primarily photo-based be expanded to include genetic identification and data 

gathered from any future biopsy sampling effort, as well as data obtained from stranded belugas. 

This would provide a multidimensional record of individual histories to include information on 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-4

movements, and interactions among genetics, reproductive states, condition, stress levels, and 

other health indicators. In turn, these results can be analyzed to estimate abundance, determine 

age structure, mating patterns, and social structure, and to detect changes in fecundity, health, 

condition, and mortality risk with respect to variation in environmental and anthropogenic 

factors.

CI belugas that are necropsied or sampled alive can be identified and linked to individuals in 

the photo-identification catalog, which also maintains a sighting history (i.e., dates and locations 

individuals have been seen, as well as group associations and female reproductive history). 

Expanding the database to be a multidimensional record of analytical findings from individual 

whales, paired with each individual’s life history, would allow analyses across disciplines. Metaanalysis of life history information, contaminant levels, and other findings from related analyses 

could better highlight critical life stages and/or effects of contaminants.

5. Determine annual mortality and reproductive rates of CI belugas.

Promote and coordinate research efforts to measure and monitor annual mortality rates 

(including juveniles) and reproductive rates of CI belugas and relate these to variation in 

available prey and other environmental variables. A number of research methods such as skin 

and blubber biopsy, photo-identification, stranding investigation, aerial survey, or scat collection 

can contribute data to this effort. Analyses such as mark recapture using photo-identification and 

genetic data, hormone levels in scat or blubber, and population distribution, abundance, and 

calving rates from aerial survey and individual database data will contribute to this effort. 

Knowing the relative significance of change in reproduction versus survival rates may also guide 

other research.

6. Conduct regular biopsy surveys of CI belugas to monitor changes in condition and 

reproductive success in relation to environmental changes.

Body condition, contaminant levels, reproductive status, and stress levels can potentially be 

monitored using a skin and blubber biopsy (this sampling approach has been effective and 

benign on a number of species). Regular biopsy surveys of the CI beluga could provide data 

necessary to relate survival and reproductive status to environmental and anthropogenic factors

and could better inform population models. Any such sampling should be conducted per NMFS 

AKR’s biopsy guidance (NMFS 2015).

Note: Because this recovery task involves invasive methods, it will require both MMPA and 

ESA authorizations from NMFS. Any invasive research methods involving CI belugas should be 

developed in conjunction with the NMFS AKR.

7. Organize an annual review and coordination workshop to review existing data on individual 

CI belugas, plan expansion of future data collection and analyses, and facilitate linkage of 

all existing and new CI beluga-related research.

NMFS should hold annual workshops to review and integrate existing CI beluga data, to 

discuss approaches for collecting more integrative individual data in the future, and to plan 

analyses that would improve our understanding of the CI beluga population. For instance, 

improving knowledge of CI beluga demography could be a topic for specific review and 

discussion.
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VI-5

The CI beluga population is sufficiently small that data on individual whales’ histories are 

needed to identify and quantify risks to this small population. Currently only photo-identification 

data are collected in a systematic manner. Other types of data for individual whales, such as 

genetic, acoustic, contaminant load, body condition, and mortality, are collected 

opportunistically and held by several different research groups. Hosting an annual research 

workshop to connect projects working on different analyses would also encourage sharing of 

data, and maximize linkages among the stranding response program and other ongoing research

efforts.

8. Hold a workshop to consider the feasibility, risks, and benefits of different sampling 

techniques such as breath capture, remote ultrasound, and live captures to obtain samples 

and measures for further analyses.

A complete health assessment requires capture of a beluga for blood sampling and other 

procedures, but can provide invaluable information not generally obtainable by other less 

invasive techniques, such as biopsies or breath capture. Such less invasive techniques can 

provide some information about the health of an animal and do not require capture and handling 

of animals. However, these techniques still require close approaches to the whales to collect 

samples (and therefore pose a risk of physical harm) and also carry the risk of disturbing 

animals. Caution in close approaches is warranted to ensure that the research itself does not 

adversely affect the whales or unnecessarily alter their behavior.

Before committing to or approving any large-scale invasive research sampling program of CI 

belugas, NMFS should convene a workshop to review research techniques and CI beluga 

behavior and to recommend best practices that will minimize impacts to CI belugas and ensure 

maximum benefits from the sampling. Workshop participants should consider the risks and 

benefits of all available procedures, develop recommendations for sampling and assessment, and 

specify which information can only be obtained through live captures. The workshop should also 

develop a protocol to monitor the effects of such sampling, including criteria to determine 

whether sampling should be discontinued if adverse effects are detected. Potential protocols 

should be evaluated through a pilot study with a healthy beluga population before being applied

to the Cook Inlet population. The report from a NMFS-sponsored workshop specific to biopsy 

sampling is available on the NMFS AKR website at: http://www.alaskafisheries.noaa.gov/pr/cibelugas.

9. Conduct a workshop to update a model to determine the probability of extinction of CI 

belugas.

The PVA model used by NMFS in the decision to list CI belugas as endangered should be 

reviewed, and if appropriate, updated at each 5-year review or status review. Updated population 

models should include spatial distribution and should incorporate explicit models of threats and 

those threats’ interactions and impacts on CI beluga survival and reproduction by age and sex. 

Future PVA models should also address levels of quasi-extinction24 and thresholds that result 

 

24 Quasi-extinction is defined as the population threshold where risk factors such as inbreeding depression, loss of genetic 

diversity, vulnerability to disease, vulnerability to predation, or dependence on limited resources intensify as the population 

declines to the point that there is no possibility of recovery for the population. This is likely beyond a level that is fully 

accounted for in the PVA model so that, while extinction may be considered certain, the timing of extinction may not be well 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-6

from small population effects. A workshop, or series of workshops, should be conducted to 

address these issues, possibly following the model of the SouthEast Data, Assessment, and 

Review (SEDAR) program.

25 Workshop topics could include: 1) defining what data are missing 

and discussing how to design and fund studies to obtain the missing data; 2) compiling and 

reviewing the latest data to be used in the PVA; 3) developing a PVA that incorporates various 

threats and considers cumulative effects; and 4) evaluating the results from a new PVA to 

estimate probability of extinction. Workshop(s) should repeat on a period basis, incorporate new 

information, and be compatible with the five-year update requirement for NMFS ESA status 

reviews.

10. Engage in education and outreach efforts targeted at informing the public of the status of CI 

belugas and their threats, and promoting more public involvement in reporting CI belugas.

To promote public awareness and support for the CI beluga recovery program and the 

management actions necessary to support recovery, effective education/outreach efforts as well 

as public participation are needed. Suggested actions are listed below; however, this is not an 

exhaustive list.

10a.Provide information regarding threats to CI belugas and ways the public can help

mitigate those threats.

Throughout the CI beluga recovery process, information updates should be provided to 

stakeholders, interested parties, and the general public regarding the status of the population and 

the steps taken to: 1) improve and refine knowledge of CI beluga life history, biology, and the 

threats that may be limiting recovery; and 2) implement management actions to promote 

recovery. This information can be communicated by developing and distributing educational 

materials, presenting updates at public meetings or conferences, posting updates on the NMFS 

AKR website, and disseminating news releases to the media. One of the midwinter meetings in 

Anchorage, such as the Alaska Marine Science Symposium or the Forum on the Environment, 

could be used for an annual public review of CI beluga research findings, future research plans, 

and other recovery-related topics. Some of the specific topics that should be communicated to 

stakeholders, interested parties, and the public, include the following:

• Acoustic impacts: There is a general underestimation of the importance of the acoustic 

environment to CI belugas and other odontocetes in general. There may also be an 

underestimation of the impacts of anthropogenic noise to CI belugas. Many users of Cook 

Inlet are not aware of the noise their activities (e.g., outboard motors) can introduce into 

the water and how this noise can negatively affect CI belugas. An awareness campaign 

about underwater noise pollution and the importance of sound to CI belugas would make 

this information available to the public and would encourage good habits and responsible, 

considerate coexistence with CI belugas.

 

determined. For example, Krahn et al (2004) defined the quasi-extinction level for Southern Resident killer whales as the 

level at which the population would be “doomed” to extinction, even though literal extinction might still take decades for 

long-lived mammals.

25 The SEDAR website can be found at: http://sedarweb.org.
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

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• Habitat loss: Reducing the rate of habitat loss or restoring lost habitat comes with a cost 

and often involves tradeoffs. The outreach and education program could acquaint/update 

stakeholders and the general public with the costs and benefits of ongoing mitigation and 

restoration measures and the results of such measures.

• Direct disturbance or injury: Annual notices/reminders should be disseminated to private 

boaters, subsistence users, commercial fisheries, cargo ships, and other vessels (including 

those engaged in recreational sport activities) describing how to avoid whales and share 

Cook Inlet with belugas and other marine mammals and encouraging immediate 

reporting of harassment or trauma. If whale-safe boating recommendations or other 

guidelines (e.g., responsible viewing guidelines) are developed, this information should 

be distributed annually to potential users.

10b.Develop and broadcast annual announcements promoting the use of citizen science and 

encouraging reporting of strandings and sightings by the public.

Given the remoteness of CI beluga habitat, ongoing monitoring for strandings or other 

catastrophic events could occur to some extent at the local level and should involve the

development and implementation of a community-based, citizen science beluga monitoring, 

sighting, and stranding program throughout Cook Inlet. The community-based CI beluga 

stranding program could serve as a mechanism to increase stakeholder involvement in the 

stranding program while reducing overall costs. Prompt identification and proper reporting of 

beluga carcasses is essential to maximize the quality and quantity of samples and to determine 

cause of death. All posted signs that encourage such reporting should be evaluated annually for 

accuracy of information. Annual reminders with a single 24/7 stranding reporting phone number 

should be sent directly to people who are most likely to encounter carcasses such as ADF&G and 

commercial entities active on the Inlet. Additionally, repeated, annual public service 

announcements through a variety of avenues (radio, TV, the web, social media, and printed 

material for boaters, fisherman, and pilots via harbormasters, fishing license distributors, or flight 

control centers) will serve to remind the general public of the importance of promptly reporting 

strandings. Such announcements could be combined with messages regarding responsible 

viewing and boating and how to report incidental sightings. The community-based beluga 

program members could include pilot organization, boaters, fishing groups, hunters, school 

groups, senior groups, as well as existing sighting networks (e.g., Coastal Observation and 

Seabird Survey Team, Alaska Native Sentinel Program, Friends of the Anchorage Coastal 

Wildlife Refuge Beluga Surveys, Cook Inlet Keepers, the Alaska Ocean Observing System, and 

the CI beluga photo-identification project’s “Seen Belugas?” sighting program).

10c. Create an annual Cook Inlet Beluga Watch Day.

Using the example of the Audubon Society’s Christmas Bird Count, or the “Whale Watch 

Week” along the Oregon Coast, create an annual “Cook Inlet Beluga Watch Day” to promote 

local pride, awareness, and stewardship of Cook Inlet and CI belugas. A single day can be 

selected to conduct Inlet-wide beluga counts, educational talks, public service announcements, 

and outreach events. Ideal days would be in late August when whales are most-visible around 

Anchorage and along Turnagain Arm and when many summer visitors are still in the state and 

local schools are back in session; alternatively a day in the spring when many schools in 

southcentral Alaska would be available to participate during Sea Week. In addition to fostering 

public support for CI belugas, this type of activity will produce basic information about the 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-8

location of belugas throughout the Inlet on a single day that could be used by CI beluga 

researchers and managers. This type of effort will likely require collaboration with several 

groups and organizations.

11. Improve the stranding response program for both live and dead CI belugas.

In 2009, NMFS AKR updated its stranding response plan for Cook Inlet beluga whales;

however, that document is lacking in specificity in many ways, does not account for new 

technology, and does not emphasize the importance of the public in a timely and effective 

stranding response. A revised and robust stranding response plan is required in order to expand 

the existing program for responding to live-or dead-stranded CI belugas in a manner that is safe 

for both response personnel and the animals and that allows for timely access to stranded 

belugas. Improvements need to be made to increase the number of stranding responses (relative 

to reported strandings) and to decrease the stranding response time. Improvements will require 

increased and reliable funding for CI beluga stranding response personnel and increased effort 

for training, coordination, and outreach. This funding should be independent of funding for other 

research or management activities.

In cases where live-stranded animals are reported promptly and conditions are safe for onsite response, a vast amount of information can be obtained through bio-sampling, individual 

identification of animals, and tracking animals after they re-float and resume swimming freely. 

Results from a thorough bio-sampling program of live strandings could inform researchers about 

the current causes of decline or impediments to recovery. In general, greater communication and 

coordination is needed to increase the speed and completeness of responses, and options to 

achieve hands-on responses to live strandings need to be more thoroughly explored. 

Policies/protocols on the collection of samples, hearing testing, and attachment of tags to live 

animals are needed. In updating the plan, consideration should be given to responding preemptively to atypical situations, such as live entangled belugas, prior to animals becoming 

stranded.

The current primary method of obtaining samples from dead stranded CI belugas for 

determining cause of death or an individual’s health is to collect samples from carcasses. Since 

information vital to determining the cause of death degrades the longer the animal is dead,

prompt discovery and proper reporting of carcasses is essential for maximizing the quality and 

quantity of samples that can be collected from a dead CI beluga. In particular, the tissues which 

are necessary for examining the presence of disease and contaminants, or assessing whether there 

is damage to the auditory system, decay quickly after death, which can prevent such evaluations.

Oftentimes NMFS or a NMFS-authorized stranding responder is not able to get to a dead CI 

beluga quickly enough to examine these tissues. Reasons include the remoteness of many of the 

dead whales (either floating away from shore, or in locations limiting easy access), and the 

timeliness of the response (either because it was not reported to NMFS in a timely manner, or 

other constraints prevented an immediate response). Some of these factors are uncontrollable, but 

others can be improved upon. By encouraging immediate reporting of carcasses, the overall time 

to response can be improved and better quality data (i.e., less decomposed tissues) can be 

collected. With the highly dynamic tides in Cook Inlet, stranded carcasses rarely stay in one 

place for long, and floating carcasses can move a mile within 15 minutes. Thus, the best time to 

secure a carcass is when it is first observed. However, logistical and communications difficulties 

around Cook Inlet often prevent carcasses from being secured by authorized personnel. In order 

to achieve maximal use of beached carcasses, the process needs to be streamlined; authorization 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-9

for observers to secure carcasses should be issued within 15 minutes of the request; and sampling 

teams should be on site within three hours. A stranding response plan needs to be quick, 

efficient, effective, and user-friendly. A sufficient number of trained response personnel need to 

be available, and supplies need to be on hand and ready for deployment. Additionally, to 

minimize cross-contamination or environmental contamination that can obscure the presence of 

disease in samples, necropsies are better done in covered areas, ideally within a necropsy 

laboratory. In the best case situation, the Alaska Marine Mammal Stranding Network would have 

access to indoor laboratory space sufficient to examine a beluga, and would have the means to 

transport carcasses to the laboratory.

Moreover, documentation of supplemental information associated with live- and deadstranded CI belugas should include data such as weather, tidal height, fish run status, acoustic 

disturbances, and killer whale presence. Also, the CI beluga stranding data should be better 

integrated with the photo-identification catalog and other CI beluga databases, including 

incidental sightings. Photo-identification of individual belugas being necropsied may allow life 

history information in the photo-identification catalog to be linked with necropsy findings, 

potentially highlighting life stages or other life-history information associated with increased risk 

of exposure to disease or other stressors. There should also be ongoing (at least annual) analysis 

of the stranding data, rather than sporadic reviews. Finally, the geographic range of, and 

participation in, the stranding network in Cook Inlet be expanded, and the establishment and 

oversight of new network hubs in areas currently lacking coverage should be coordinated by 

NMFS with assistance from the Cook Inlet Beluga Recovery Coordinator.

12. Once every five years, reassess the status of the CI beluga population and each of the threats 

to CI belugas.

Every five years, the status of the CI beluga population will be reassessed and a 

determination made if downlisting or delisting may be warranted as required by ESA section 

4(c)(2). Thus, at least once every five years, a reassessment should be undertaken of each of the 

threats to CI belugas (including those ranked of low relative concern) to reevaluate whether they 

are limiting or precluding recovery, and that information can be used in the CI beluga population 

status review. For threats ranked as medium or high relative concern, if a reassessment suggests 

a threat is not limiting CI beluga recovery, then this threat should continue to be monitored and 

reassessed in the subsequent five years to confirm the previous assessment. Upon confirmation 

of the previous assessment, such a threat should be re-ranked as “low” relative concern. This 

confirmation provision is included to ensure that any such re-ranking is addressed 

conservatively. Alternatively, if a reassessment indicates there is still medium or high relative 

concern regarding the threat, then the related threats management actions identified in this plan 

should continue to be implemented or new actions defined.

Given changing conditions in Cook Inlet, either from environmental forces (e.g., as a result 

of climate change or an increase in predation) or anthropogenic activities (e.g., increased 

development), threats currently ranked as being of low relative concern may be of greater 

concern in the future. If a reassessment indicates that the significance of a threat previously 

ranked as low relative concern has elevated to medium or high relative concern, specific 

recovery actions should be defined to address that threat. During each five-year review, any new 

threats not previously identified in the recovery plan can also be addressed. This provision for 

periodic reassessments of the threats to CI belugas is included to ensure the recovery program 

remains strategic and effective in addressing the threats that matter most at a given time.
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

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VI-10

THREATS MANAGEMENT ACTIONS:

Reduction in Prey

A primary uncertainty in trying to understand the failure of the CI beluga population to 

recover is whether the quantity, quality, and/or seasonal phenology of available prey is limiting 

population recovery through constraints to CI beluga reproduction and/or survival. It is important 

to conduct analyses to understand if a reduction in prey is occurring and if so, the effect such 

reductions are exerting upon CI beluga recovery. To fully understand whether adequate prey is

available we must also improve the level of understanding of CI beluga prey dynamics and CI 

beluga energetic requirements. While belugas are known to eat large amounts of fish in spring 

and summer, little is known about winter distribution and less about winter feeding. Studies of 

CI beluga prey should therefore include winter months when possible and pertinent.

Fisheries management (e.g., escapement goals for CI beluga prey species) needs to 

adequately accommodate CI beluga prey requirements. At this time, there is only limited 

information on the characteristics of potential prey in CI beluga habitat, and available data are 

largely from the summer season. To develop appropriate mitigation measures, it is imperative to 

collect and monitor information on available prey resources to determine which, if any, prey 

resources may be limiting CI beluga recovery and to ensure implemented mitigation measures 

have the greatest likelihood of facilitating CI beluga recovery. Throughout this research, it is 

critical that emphasis be placed on determining prey quality (e.g., energetic content, 

contaminants, stable isotopes, and fatty acids) because a large quantity of poor-quality prey may 

have little utility to CI belugas relative to high-quality prey. Increased information allows a focus 

of mitigation efforts on aspects likely to promote, or not inhibit, CI beluga recovery.

13. Evaluate how prey abundance and availability has changed over time in comparison to CI 

beluga abundance and if there are direct correlations between the two suggestive of a 

positive link between prey abundance or availability and CI beluga abundance, productivity,

or mortality.

Abundance estimates are lacking for many potential prey within the range of CI belugas. 

However, some information may be generated by examining historical trends in population 

indices. A retrospective analysis should be conducted to explore correlations among annual 

deviations in population indices of CI beluga and their potential prey. Any such analysis is likely 

to be highly qualitative, as data on many of these parameters (especially time series of abundance 

for non-commercial fish prey species) are lacking. Changes in seasonal phenology of available 

prey over time should also be considered in such an analysis, although data on this aspect of prey 

availability are likely limited.

14. Monitor body condition of living and deceased CI belugas to assess the presence/absence of 

nutritional distress or nutritional-related mortalities, and determine the percentage of 

necropsied CI belugas with mortalities attributed to nutritional distress.

Body condition of individual CI belugas can provide insight to the nutritional status of the 

whale. For live whales, non-invasive methods such as photo-identification studies or minimally 

invasive methods such as biopsies may prove useful for assessing body condition over time.

Necropsies of dead whales and subsequent analyses of samples will be necessary to determine if 

nutritional distress was associated with cause of death. A review of the photo-identification 

catalog and previous necropsy reports looking for evidence of nutritional distress or nutritional-
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-11

related mortalities may be useful in determining the proportion of the population that may be 

exhibiting signs of nutritional distress. However, any assessment will have to take into 

consideration the seasonal changes in CI beluga body condition (animals thin out during the 

winter and fatten up during the summer). Assessments should also consider that poor body 

condition of a dead whale may be associated with a condition unrelated to prey abundance. Also, 

body condition may not be responsive to nutritional stress until that condition becomes severe.

This is because a portion of the blubber may be dedicated to insulation rather than active energy 

storage, and not reduced until other fat reserves are depleted.

15. Analyze the existing collection of CI beluga teeth to determine if the age at first reproduction 

for female CI belugas can be determined, and assess if there has been a significant change in 

this parameter over time.

In addition to assessing body condition, which may be misleading for various reasons, 

another pathway to determine whether animals are experiencing nutritional distress is to examine 

the age at first reproduction. If the age at first reproduction increases over time (i.e., the first 

reproduction occurs later in life), it may be an indication of nutritional stress adversely affecting 

reproduction, whereas a decrease in age at first reproduction over time (i.e., the first reproduction 

occurs earlier in life) may indicate that food is not limiting recovery. Studies have successfully 

analyzed teeth to determine the age at first reproduction (e.g., see von Biela et al. 2008). This is a 

non-invasive method that does not require any harassment or harm to living CI belugas, as the 

teeth are collected only from dead whales and CI beluga teeth have previously been analyzed for 

age. NMFS is currently in possession of previously collected teeth. This methodology has the 

potential to improve our understanding of whether nutritional stress is adversely affecting 

reproduction, and could more accurately and precisely define an important life history parameter 

(age at first reproduction), which is currently extrapolated for CI belugas from other beluga 

populations and captive belugas.

16. Review available data which may provide information about calving rate (population-wide)

or calving interval (individual belugas), and assess whether either of these parameters is

correlated with prey abundance.

When animals are nutritionally stressed they may forego or postpone costly reproductive 

activities until they have the energetic reserves to undertake such a physically costly activity.

Like age at first reproduction, changes in the calving rate may be correlated with individual 

health and food availability. If there is a reduction in prey, the calving rate may decrease, or the 

calving interval may increase. Thus, information about these parameters (calving rate and 

calving interval) should be reviewed to determine if there has been a change in these life history 

parameters over time and if there is any correlation in these parameters with prey abundance.

17. Research the seasonal, spatial, and size variation in prey diversity and quality to improve 

assessments of relationships between CI belugas and their prey.

Because not all CI beluga prey species are created equal and because the nutritional 

characteristics of a given prey species vary seasonally, research is needed to understand the 

quantity, quality, distribution, and availability of CI beluga prey, and how these parameters vary 

spatially and seasonally. Although some information is available on the upstream spawning 

escapements of some prey species in select Cook Inlet tributaries, this does not provide a clear 

understanding of the prey available in the marine/estuarine areas. There is also a paucity of 

information on prey available from late fall to early spring, and on the quality of CI beluga prey 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-12

resources (e.g., energy content, contaminants, stable isotopes, fatty acids). Standardized surveys 

are needed to determine the spatial and seasonal distribution of beluga prey in upper Cook Inlet. 

Data on levels and types of fatty acids and stable isotopes among predator and prey organisms 

can be used to better understand seasonal trophic linkages (i.e., the relationship between potential 

predators and potential prey species at different times of the year). This information is an 

important component of the data needed to understand CI beluga foraging patterns. Data are 

collected through tissue samples of prey species for comparison to stable isotopes in beluga 

blubber fatty acids and skin. Belugas swallow their prey whole, so smaller (younger) belugas 

require smaller prey. Consequently, the size of prey is also a relevant consideration. Further, the 

smaller body size of young belugas does not allow them to store as much energy as larger, older 

belugas. Thus, juvenile survival may be particularly influenced by the availability of smaller 

sized prey in late fall and early spring.

18. Research the effects of environmental and anthropogenic factors on CI beluga prey to assess 

if any particular factor is having a significant detrimental effect to the prey and thus a 

detrimental effect on CI beluga recovery.

Factors such as tidal mixing, temperature, salinity, sedimentation, and contaminants affect 

the characteristics of the aquatic environment. Prey species that have high mobility may seek 

better aquatic habitat conditions in areas not currently exploited by CI belugas. While prey that 

spend extended periods of time in suboptimal environments are not likely to attain optimal body 

condition and will not provide optimal CI beluga forage, the relationships among environmental 

factors and prey distribution and quality remain poorly understood and need further research. 

This research could include the development of predictive models of prey availability based on 

changing environmental or anthropogenic factors, and a variety of collaborative studies, for 

example, to understand the status of upper Cook Inlet salmon stocks, particularly the declines of 

Chinook salmon. Spatial distribution of many fish species is often associated with aquatic fronts 

defined by environmental boundaries. Anthropogenic factors can introduce new aquatic fronts, 

such as boundaries created by chemical releases or downstream plumes resulting from sediment 

disturbances, sewage outfalls, or other point sources of pollution requiring mixing zones. Given 

our lack of understanding about how different aquatic fronts determine CI beluga prey 

distribution, additional research is needed to determine how anthropogenic alterations to the 

aquatic fronts may affect the timing and distribution of prey.

The impact of fishing pressure on spatial and temporal prey availability within CI beluga 

habitat is poorly understood, especially for non-salmonid species, such as eulachon and Pacific 

herring, that are targeted by fisheries, but for which stock assessments are lacking. While fishing 

can reduce prey availability in CI beluga habitat within the fishing season, the impact on future 

recruitment is less well known. Also, the impacts of anthropogenic noise on potential prey in CI 

beluga habitat is poorly understood, rarely considered, and in need of further study. If the result

of anthropogenic activities, such as fishing or noise, is a loss of feeding opportunities or 

reduction in prey for CI belugas, there will likely be an adverse effect to the belugas. 

Consequently, these effects will be most important to beluga recovery in areas preferred for 

feeding and during times of the year when energetic demands are greatest (e.g., pregnancy and 

lactation). Mitigation techniques have already been proposed to reduce impacts upon fish from 

some sources, such as pile driving. Further research is needed to improve mitigation techniques, 

especially for noise sources where no mitigation is yet proposed.
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

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VI-13

19. Determine energetic requirements/metabolic needs of CI belugas at different life stages to 

determine whether nutritional stress is a function of life stage.

Energetic requirements of belugas and the utility of potential prey items to meet metabolic 

needs vary seasonally and by CI beluga life stage. For example, newborn CI beluga calves have 

few fat reserves and are dependent on milk to quickly grow in length and girth and to develop fat 

reserves over the first year; consequently, inadequate reserves may reduce the ability of calves or 

juveniles to survive overwinter. Pregnant and nursing females are subjected to additional 

energetic demands, and all belugas must enter the winter with sufficient energetic reserves to 

survive several months of presumed low energetic input and high basal metabolic demand. While 

the rate at which energetic reserves are used presumably varies by CI beluga sex and life stage, 

details are currently unknown. Sampling to determine seasonal body condition by CI beluga sex 

and life stage would facilitate a better understanding of potential stressors and how to mitigate 

against such stressors. Understanding metabolic needs may also be informed through analyses of 

body condition and food intake by belugas maintained in aquaria.

20. Study the diet selectivity of different CI beluga demographic groups (e.g., age, sex, and 

reproductive state).

Because CI beluga metabolic needs vary by sex and life stage, dietary needs typically respond 

to metabolic demand. Diet selectivity would conceivably be a function of caloric return on 

metabolic investment of foraging. That is, predators target prey providing high nutritional input, 

but if highly nutritional prey are encountered only infrequently, the predator diet would include 

less-nutritional but more frequently encountered prey. Smaller (younger) belugas are also limited 

to smaller-sized prey. Few data exist to understand prey selectivity by CI beluga and how 

selectivity might change over time and in response to changes in the available prey.

Prey selectivity by CI belugas is also expressed in foraging habitat preferences. For example, 

foraging may be easier in river mouths with steep banks, in areas of good echolocation 

conditions (good water mixing and limited suspended sediment), or in areas where prey behavior 

favors capture (e.g., anadromous fish adapting to changes in salinity when entering rivers). 

Spatial considerations must be included when examining foraging behavior and developing a 

foraging model for CI belugas. This action would use stomach contents and other observations to 

examine what prey are consumed relative to the available prey.

21. Using currently available information, develop a CI beluga foraging model informed by prey 

characteristics and beluga dietary needs.

Combining data on CI beluga dietary needs, beluga foraging strategies and efficiencies, and 

prey characteristics will allow development of a CI beluga foraging model. Such a model will 

allow examination of tradeoffs among potential prey species and the importance of potential prey 

in different seasons and at different CI beluga life stages. This model would be informed by 

seasonal fatty acid and stable isotope signatures of prey species, energetic 

requirements/metabolic needs by life stage, and observed foraging selectivity by different CI 

beluga life stages. A foraging model would provide insights into whether CI beluga reproduction 

and survival are being limited by available prey and would help to identify potential mitigation 

measures to improve CI beluga recovery.
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Recovery Plan A. Recovery Actions and Narrative

VI-14

22. Ensure fisheries management (e.g., escapement goals for CI beluga prey species) adequately 

accommodates CI beluga prey requirements, and if necessary, expand the number of species 

with escapement goals.

Escapement goals and management measures for salmon and other CI beluga prey do not 

explicitly incorporate CI beluga dietary needs. Salmon production models that provide the basis 

for ADF&G management measures typically allocate mortality as either human harvests or 

natural mortality, which implies that CI beluga prey needs are treated as an unspecified 

component of natural mortality. In addition, natural mortality for salmon is either treated as fixed 

or assumed to occur across a relatively small range of values. At the simplest, a perceived 

reduction in a stock targeted for human consumption results in management measures to reduce 

harvest levels, with the harvest reduction (down to some threshold level) often proportional to 

the level of stock reduction. However, because the consumptive prey needs are relatively stable 

for a given CI beluga population size, a declining prey resource base implies a relative increase 

in the proportion of a prey resource needed for CI beluga consumption. Thus, the aggregate 

natural mortality rate may actually increase as the prey resource declines.

Consideration of measures to adequately provide for CI beluga prey consumption may be 

even more important for prey resources for which there are no ongoing stock assessments. For 

example, many of the salmon stocks returning to Cook Inlet tributaries are not actively assessed, 

but may be assumed to fluctuate similar to an index salmon stock returning to a nearby tributary. 

However, in the case of eulachon, there is no assessment program, and any decline in eulachon 

stock productivity or at-sea mortality rate might not be detected until after several years of 

fishery harvest declines. ADF&G should ensure the management of anadromous species 

considers CI beluga dietary needs, particularly in a way that provides for a sustained abundance,

density, and temporal availability of returning fish as prey in CI beluga feeding areas. This may 

require review of the models being used to manage fisheries in Cook Inlet to gain insight about 

the potential effects of these fisheries on the Inlet’s ecosystem.

Disease Agents

Disease agents are considered a threat of medium relative concern, but the degree to which 

they may be limiting CI beluga recovery is uncertain. There is a need to not only assess if disease 

agents (pathogens, parasites, harmful algal blooms) are limiting CI beluga recovery, but also to 

improve our understanding of the sources of disease agents in Cook Inlet. Monitoring living CI 

belugas via non-invasive methods, such as photo-identification studies, or minimally invasive 

methods such as biopsies, and deceased CI belugas via necropsies, will provide information 

regarding the presence/absence of disease agents or disease-related mortalities.

23. Analyze images from the CI beluga photo-identification catalog for the presence of external 

signs of disease in photographically identified CI belugas to 1) assess the percentage of 

identified CI belugas with external indications of disease, and 2) track the persistence of, or 

changes in, the external indications of the disease agent in individual whales over time.

The CI beluga photo-identification catalog includes many belugas bearing skin lesions 

consistent with localized and systemic infections. The number of individual belugas in the photoidentification catalog with such lesions should be quantified, analyzed by disease experts to 

identify probable cause, and monitored over time to determine trends in the incidence and 

prevalence of these conditions.
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-15

24. Continue examining beach-cast carcasses of CI belugas for disease-related mortalities, 

assessing the percentage of necropsied CI belugas with mortalities attributed to disease 

agents, and linking results from examinations of known individual belugas with the CI beluga 

photo-identification catalog. When feasible, determine the presence and relevance of disease 

agents in other Cook Inlet marine mammal mortalities.

The current primary method of obtaining samples from CI belugas for disease testing is by 

sampling of stranded carcasses. Because evidence of disease is quickly obliterated by post 

mortem decay, it is essential to be able to initiate necropsies as soon as possible after death and 

specifically look for the presence of disease agents. Identifying the individual whale being 

necropsied, when possible, will allow life history information in the photo-identification catalog 

to be linked with disease findings, potentially highlighting life stages or other life-history 

information associated with increased risk of exposure. Given the limited number of CI belugas 

available for sampling for disease assessment, researchers should consider alternate methods of 

inferring disease risk to CI belugas, such as examining other marine mammals found dead in the 

Inlet that use similar prey resources (e.g., harbor seals or harbor porpoise), which may provide 

evidence of diseases of concern that may be transmissible to belugas.

25. Using currently available information, compare data on diseases from CI belugas with other 

beluga populations to determine if there are abnormal levels or atypical types of disease 

agents present in Cook Inlet affecting CI belugas.

Diseases are present in all animal populations, even healthy ones. Understanding which 

diseases, and at what levels, are present in other beluga populations is key to understanding 

which diseases may be negatively impacting this endangered population. Therefore, having 

disease data that were obtained and analyzed using techniques similar to those used on other 

beluga populations (e.g., Bristol Bay or Point Lay, Alaska) helps to determine whether CI 

belugas are experiencing an abnormally high incidence of disease.

26. Determine types and sources of disease agents identified to be of concern specifically to CI 

belugas and assess management actions targeted at mitigating the disease agents.

Belugas can be exposed to disease agents through ingestion (of prey, or of water consumed 

with prey), close contact with other mammals, inhalation, and contact with the water in which 

disease agents are present. Disease agents demonstrated to affect CI belugas should be 

investigated to determine possible routes of transmission and potential for disease. Investigations 

should focus first on the most likely disease source or the disease agent that is most readily

mitigated. In conjunction with nutritional and toxicological analyses, prey could be analyzed as 

possible vectors of disease. Transmission from terrestrial sources should also be considered (e.g., 

sewage outflow, animal waste, anthropogenic contaminants in runoff). Additionally, routine 

water quality monitoring and disease monitoring in other Cook Inlet mammals should be 

established or continued. Collaboration contributing to the analysis of such monitoring is 

encouraged, especially as it relates to CI beluga recovery.

Noise

Given that certain noise levels are a threat of high relative concern, it is important to assess if 

noise is limiting CI beluga recovery by resulting in behavioral responses such as live strandings 

or displacement from important habitats. To adequately address the threat posed by noise, there 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-16

is also a need to improve the understanding of the acoustic environment of Cook Inlet and the 

management of noise-producing activities in the Inlet.

27. Conduct a retrospective analysis of documented CI beluga live strandings and noiseproducing anthropogenic activities in Cook Inlet, possibly to include the development of a 

database of anthropogenic activities that introduce noise to Cook Inlet, and assess if a 

correlation exists which may indicate noise is limiting CI beluga recovery.

If certain noise conditions have the potential to trigger CI beluga strandings, it is critical to 

consider these noise conditions in the CI beluga recovery plan. Although CI belugas are known 

to strand, the relationship with anthropogenic activities has not been thoroughly evaluated. 

Because anthropogenic noise may cause mass strandings, this risk needs to be evaluated for CI 

belugas. Archived information on CI beluga strandings and the timing of historical 

anthropogenic activities known to introduce acoustic energy into the water should be compared.

A geospatial database should be developed to record data on anthropogenic activities known 

to introduce acoustic energy into the water (e.g., the timing, duration, acoustic characteristics 

[source level,

26 spectral contents,27 tonal,28 and pulsive29 nature, etc.], and location of these 

activities, along with any mitigation applied). This database should be linked to the NMFS CI 

beluga stranding database to allow detection of potential relationships between anthropogenic 

noise events and strandings. This open-access database should be developed, maintained, and 

managed by NMFS in collaboration with university, private, agency, and industry researchers

working in Cook Inlet.

Due to the lack of long-term background noise monitoring and the absence of baseline data 

on background noise in Cook Inlet, historical trends can only be determined by analyzing the 

history of anthropogenic activities known to introduce acoustic energy into the water. Changes in 

these activities spatially or temporally over time could have strongly modified the acoustic 

environment of certain areas. This analysis could also identify anthropogenic activities that have 

the potential to generate future chronic changes to the acoustic environment of CI belugas.

28. Conduct a retrospective analysis of anthropogenic noise-producing activities in Cook Inlet 

and information on CI belugas’ behavior and distribution to assess if a correlation exists that

may indicate noise is limiting CI beluga recovery.

To understand whether noise is limiting CI beluga recovery we need better information on

noise-producing activities in Cook Inlet and CI beluga exposure and response to those activities.

We know there are both anthropogenic and natural sources of noise in beluga habitat, and 

belugas in general are very dependent on acoustic communication. But these two things alone do 

not provide us information useful to determine if anthropogenic noise in Cook Inlet is limiting CI 

 

26 Sound intensity at the source, normally measured as dB re 1 μPa at a distance of 1 meter from the central part of the sound 

source.

27 The distribution of acoustic energy across all frequencies influenced by the noise source. 

28 Narrowband (few frequencies), modulated or not, acoustic signal of long duration (in the order of tenths of seconds to many 

seconds) (e.g., a whistle).

29 Broadband (many frequencies), normally sharp, short (in the order of milliseconds to tenths of seconds) acoustic signal (e.g.,

explosion).
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VI-17

beluga recovery. To attempt to answer that, a retrospective analysis of both noise-producing 

activities and CI beluga distribution and behavior needs to be compared over time in an effort to 

determine if noise is having an adverse effect to CI belugas (e.g., does the evidence suggest 

potential displacement or behavioral disruption of CI belugas due to anthropogenic noise).

However, a correlation alone may not be sufficient evidence to indicate noise is limiting CI 

beluga recovery, and a short-term displacement likely has less recovery implications than a longterm displacement.

29. Within areas designated as critical habitat Type 1, determine areas with high vs. low levels 

of anthropogenic noise, if there are significant typical changes (e.g., seasonal differences)

in the levels of overall (natural plus anthropogenic) noise in that area, and assess if a 

correlation exists between CI beluga use of the area and the noise levels in the area.

NMFS has designated two areas of Cook Inlet as critical habitat, with Type 1 representing 

the high use areas in the summer where large groups of belugas congregate, and areas which are 

important to reproduction and foraging activities. Given these areas are of particular importance 

to the survival and recovery of CI belugas, it is appropriate to focus an assessment of in-water 

noise on these areas. To understand if noise may be limiting CI beluga recovery requires, in part, 

a better understanding of the current characteristics of noise in the beluga habitat as defined by 

critical habitat Type 1. Both natural and anthropogenic noise sources should be assessed when 

determining the overall noise, taking into consideration that some times of the year may have 

higher levels of noise than other times (e.g., due to decreased water flows or reduced coastal 

human activity during the winter season). Once the acoustic environment of critical habitat Type 

1 has been assessed, that information should be compared to known CI beluga use of critical 

habitat Type 1 throughout the year to determine if a correlation exists between beluga use and 

noise levels of specific areas within critical habitat Type 1. However, a correlation alone may not 

be sufficient evidence to indicate whether noise is limiting CI beluga recovery. Factors 

independent of noise (e.g., seasonal anadromous fish runs) may also be influencing CI belugas’ 

use of the area. Sometimes belugas may tolerate high noise levels if the benefits of remaining in 

an area outweigh the costs of being exposed to noise in that area. If possible, these other 

parameters should be considered.

30. Describe the acoustic characteristics of different anthropogenic noise sources in Cook Inlet 

and rate the potential acoustic impacts from each type of noise source on CI belugas.

Different anthropogenic noise sources in Cook Inlet should be recorded and their acoustic 

characteristics (e.g., source level, spectral contents, tonal and pulsive nature, etc.) described. 

These noise sources should be analyzed to map their temporal and spatial occurrence in CI 

beluga habitat. All identified noise sources in CI beluga habitat should be rated based on 

potential impacts to CI beluga hearing; noise sources with higher overlap with beluga hearing, 

higher source levels, and greater spatial and temporal occurrence should receive the highest 

rating. This rating system should classify all identified noise sources in CI beluga habitat on a 

scale ranging from low (unlikely to impede recovery) to high (greatest potential to impede 

recovery). This effort should identify sources of natural and anthropogenic noise, quantify the 

overlap with CI beluga hearing, and quantify the magnitude of perturbations over space and time. 

These data should be used to map seasonal noise that is audible to CI belugas within critical 

habitat and to create a rated list of sound sources.
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VI-18

31. Conduct long-term and year-round monitoring of natural and anthropogenic noise (level and 

spectrum) in key areas where CI belugas currently and historically concentrated (including 

CI beluga critical habitat) to characterize and monitor the acoustic environment and identify 

sources, levels, and types of anthropogenic noise.

Long-term and year-round monitoring of background noise in both present-day and historical 

key areas for CI belugas (e.g., Susitna Delta and the Kenai River) has the potential to identify 

areas where the acoustic environment may no longer be suitable for belugas, either seasonally or 

year-round. Furthermore, long-term monitoring allows the establishment of present-day baseline 

levels of background noise, which are required to identify potential changes in the acoustic 

environment (e.g., periods or areas of increased noise) caused by future anthropogenic activities 

in Cook Inlet. Similarly, when noise levels increase due to several sources of input, potential 

cumulative risks can be documented.

32. Work with local, state, and federal agencies and stakeholders to develop methods and plans 

for reducing or mitigating the levels of anthropogenic noises in Cook Inlet, including 

incorporation of pre- and post-activity surveys for major noise-producing activities to 

monitor CI beluga presence.

Entities (including NMFS and industry) involved in oversight and management of noisegenerating activities should develop cooperative measures to ensure proper compliance with 

noise impact mitigation regulations (e.g., sound field verification, schedule and duration of 

activity, model and validation of exclusion zones, proper shut downs, observers and their 

working conditions, reporting audit, etc.). The NMFS has a responsibility to audit those noisegenerating activities that fall under its purview and to enforce existing regulations.

Most regulatory actions and mitigation efforts focus on the time of the activity, when noise is 

introduced into the water. However, it is equally important to obtain baseline data on the 

presence of CI belugas in areas to be affected before and after the activity. Without the 

information collected in pre- and post-surveys, it is difficult to quantify the potential impact 

generated by the activity. Because wildlife displacements due to noise have been documented at 

distances far beyond the detection ranges of visual marine mammal observers (MMOs) and/or 

passive acoustic monitoring systems, this impact can only be documented if there is knowledge 

of the presence of CI belugas before and after the activity. Several monitoring designs have been 

successfully applied to marine mammals, with before-after/control-impact design (BACI; 

Underwood 1994) being the most effective.

33. Develop and incorporate into the noise monitoring/mitigation plans a protocol to identify the 

onset (received levels and distance) of CI beluga behavioral reactions to specific activities.

Behavioral reactions to noise are among the most difficult responses to document. As part of 

standard mitigation plans, data are collected by MMOs situated on shore or on vessels generating 

underwater noise. These data can help identify the onset of behavioral reactions. Because these 

plans normally include the modeling and validation of noise introduced into the water, MMO 

data can be used to obtain distance and noise exposure levels triggering behavioral reactions. 

Implementing a requirement during the permitting of all activities in Cook Inlet that introduced 

noise into the aquatic environment to obtain these data and calculate onset of reactions would 

generate valuable information needed to update mitigation regulations in CI beluga habitat.

Because some noise effects on behavior may be difficult to detect and because such data would 
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VI-19

not account for effects that are not detectable by observation (e.g., physiological effects), such 

information would be used and interpreted cautiously.

Habitat Loss or Degradation

Habitat loss or degradation has been identified as a threat of medium relative concern to CI 

beluga recovery. To better understand the effects of this threat on CI belugas, it is important to 

assess if habitat loss or degradation has resulted in a significant reduction in the carrying 

capacity of Cook Inlet for CI belugas, or a loss or degradation of areas important to CI belugas 

for foraging or reproduction, to the point such loss or degradation is limiting CI beluga recovery.

Successful mitigation of this threat will require an improved understanding of the impacts of a 

changing habitat to CI belugas and the management of habitat degrading activities in Cook Inlet.

While both short and long-term changes occur in ecological systems, characterization of 

those changes can be difficult. Projection of future changes and ecological response to projected 

changes is even more uncertain. Characteristics of CI beluga habitat, and changes in that habitat 

over time, have not been well documented, or the documentation involves proprietary 

information associated with potential resource development. Mitigation measures to prevent loss 

or degradation of CI beluga habitat must start with an understanding of existing habitat and 

changes that have already occurred, particularly over the past 40 years when the documented 

beluga decline occurred.

Carrying capacity largely depends on environmental conditions over a series of years, or 

within a given ecological regime, and is likely to change over time. Analytical modeling 

techniques can be used to estimate current carrying capacity and to quantify the uncertainty of 

the estimate. However, the ability to estimate carrying capacity accurately depends to a large 

extent on the quality of available data. Of particular importance are the estimated numbers of CI 

belugas at different life stages; the distribution, abundance, and availability of prey species; and 

the distribution and magnitude of habitat features that may influence the productivity of CI 

belugas. For long-lived species such as belugas, development of a life-stage population model 

that accounts for differing nutritional and habitat needs across age and sex will be necessary to 

account for potential life stage variations.

NMFS has previously determined the carrying capacity of Cook Inlet to be 1,300 CI belugas.

At the 2014 estimated population size (340 whales), a small reduction in carrying capacity (e.g., 

from 1,300 to 1,000 CI belugas) is unlikely to have significant impacts to the current CI beluga 

population given its small size relative to projected carrying capacity. In this hypothetical

scenario, the reduction would be unlikely to limit the recovery potential of CI belugas; however, 

a large reduction in the carrying capacity (e.g., from 1,300 to 500 CI belugas) is likely to be a 

factor impairing the recovery of CI belugas. Thus, when conducting the assessments 

recommended below, these factors should be kept in consideration when determining if habitat 

loss or degradation is limiting CI beluga recovery.

34. Develop a comprehensive Cook Inlet environmental database using currently available 

information to conduct a retrospective spatial and temporal evaluation of the biological, 

physical, and anthropogenic features in CI beluga habitat since the 1970s and assess how 

the habitat has changed over time, including likely causes of change.

To address potential measures to facilitate CI beluga recovery, it is first necessary to

determine how CI beluga habitat has changed over time, particularly during the last 40 years 
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VI-20

when the beluga decline has occurred, and the likely causes of the change (e.g., hydrologic, 

anthropogenic, acidification, siltation, shoaling, temperature, tides, loss of upstream shade, 

installation of culverts, or other factors). Of particular interest are the biological and physical 

features of the current CI beluga habitat and how those features change seasonally. For example, 

siltation, the development or movement of sand or gravel bars, water temperature, and chemical 

characteristics of the marine and estuarine environment can be affected by localized or upstream 

drivers. Dredging, in-water construction, dams, and siltation from runoff and erosion can change 

the currents, flow, and mixing of fresh and salt water and the seasonality of fresh water inflows. 

These changes in water bodies can impact their value as prey or beluga habitat. Changes in 

hydrology of the Inlet should be studied to determine if there are impacts to belugas. These 

characteristics directly impact the suitability of CI beluga habitat, including the carrying 

capacity. Studies are needed to determine how these habitat characteristics are affected by both 

ongoing environmental changes (e.g., overall environmental change) and by anthropogenic 

factors (e.g., in-water construction or other activities).

Comprehensive mapping and spatial analyses of the characteristics of current CI beluga 

habitat in relation to current and earlier beluga distribution is needed. Analysis of the CI beluga 

survey and tagging data has been initiated by NMFS, but with limited environmental data. 

Continuation and expansion of this effort would expand the environmental aspect of this 

analysis. Unfortunately much environmental data are extremely localized or proprietary in 

association with resource development around the Inlet. Mechanisms should be developed for 

sharing and using the proprietary data and extending valuable local data to larger areas. A 

starting point would be to collect and assess the quality of data that are currently available in the 

public realm. A comprehensive Cook Inlet environmental database should be established to 

include both natural environmental data and human impacts and development, and ideally should 

result from collaborative efforts among a wide variety of public and private organizations.

35. Compare the changes in habitat availability or quantity over time with changes in CI beluga 

distribution and abundance over time to assess if a correlation exists which may suggest 

habitat loss or degradation is limiting the recovery of CI belugas.

Simply understanding if the habitat has changed over time does not resolve whether observed

changes are resulting in detrimental effects on belugas. Even negative changes or loss of habitat 

may have a limited effect on CI belugas if those changes are in locations only sporadically 

visited by just a couple of individuals. However, similar changes in locations used by large 

numbers of belugas or by few belugas all year may have significant effects on the whales.

Therefore, there is a need to compare the habitat changes over time with patterns of CI beluga 

distribution and abundance in order to determine if habitat changes are limiting CI beluga 

recovery. As previously mentioned, such a comparison will need to consider the seasonality and 

frequency of use by various whale group sizes when interpreting the results, preferably in a 

geospatial format.

36. Review losses or degradation of habitats in areas known to be important to CI belugas for 

foraging or reproduction, and assess if a correlation exists between habitat changes and 

changes in CI beluga use of the area, possibly indicating that habitat loss or degradation is 

limiting the recovery of CI belugas.

Not all of Cook Inlet has the same value to CI belugas. Some areas are more important for 

foraging or reproduction, whereas other areas seem to be primarily transit corridors or are only 
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VI-21

occasionally visited. This variability in degree of use is reflected in the designation of two 

critical habitat areas. An effort focused on areas most important for foraging or reproduction may 

provide a better indication of the effect of habitat loss or degradation on the current CI beluga 

population. While this may be useful for the current population size and distribution, we note

that if the population grows and expands its distribution to include more of mid and lower Cook 

Inlet in the summer, this focused assessment should be expanded in geographic scope to reflect 

range expansion.

37. Update the comprehensive Cook Inlet environmental database developed in Action 34 and 

project the future extent and quality of CI beluga habitat.

A potentially more complex step in assessing the quality of CI beluga habitat is to project the 

future extent and quality of CI beluga habitat. Because it is difficult to project the rate and 

magnitude of future change, given all the contributing factors, this approach should address the 

range of possible outcomes. Future habitat and development projections would then be informed 

by our updated understanding of CI beluga habitat characteristics and the temporal and spatial 

scales on which it appears changes have occurred. It is particularly important to examine 

ongoing coastal and in-water development trends and determine if anticipated development will 

negatively impact CI beluga recovery. Data compiled under Action 34 should be updated and 

analyzed to identify temporal changes in CI beluga habitat and develop ongoing or periodic 

monitoring program(s) for comparison to this baseline data.

38. Conduct a detailed habitat survey to begin long-term habitat monitoring (quality and 

quantity), including the use of volunteers and community members.

While the critical habitat of the CI beluga has been identified, there is very limited 

information, since critical habitat designation, on the current status of the habitat, existing 

impacts, and the prey available to the CI beluga. In addition, seasonal variation of many features 

is poorly known. A comprehensive survey of the habitat available to CI beluga should be 

conducted to identify available prey species, to estimate the prey biomass density by season and 

area, and to determine the seasonal levels by area of anthropogenic impacts to CI beluga habitat 

and prey. A survey of the prey habitat and anthropogenic changes would provide a baseline for 

the current level of impacts to CI belugas and provide a basis of comparison for future 

improvements to, or losses of, that habitat. Given the projected future extent and quality of CI 

beluga habitat (described in Action 37) and the suitability of those future habitat conditions for 

CI beluga recovery, long-term monitoring will be critical to guide potential mitigation measures.

Given the remoteness of CI beluga habitat, knowledge acquisition and ongoing baseline 

monitoring of CI beluga habitat use could occur to some extent at the local level. A communitybased beluga monitoring program should be developed and implemented throughout Cook Inlet. 

This could be modeled after the Alaska Native Sentinel Program. Much of the monitoring and 

assessment of current and future CI beluga habitat characteristics will involve periodic collection 

of index data. To some extent, much of the required data can be collected either directly in CI 

beluga habitat or at index sites serving as proxies to nearby CI beluga habitat. Contingent on the 

frequency and location of data collection, the community-based CI beluga monitoring program 

could serve as a mechanism to increase stakeholder involvement in the sampling program while 

reducing overall costs of the sampling program. Program members could include pilot 

organizations, boaters, fishing groups, hunters, school groups, and senior groups, as well as 

existing sighting networks (e.g., Friends of the Anchorage Coastal Wildlife Refuge Beluga 
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VI-22

Surveys, Cook Inletkeeper, the Alaska Ocean Observing System, and the CI beluga photoidentification project’s “Seen Belugas?” sighting program). The monitoring program could be 

organized and supported by the NMFS Cook Inlet Beluga Recovery Coordinator (see Action 2).

39. Evaluate impacts on CI belugas from anthropogenic activities with potential to result in 

degradation or loss of CI beluga habitat, with emphasis in known and historic feeding areas.

Construction and operation of new physical structures (e.g., bridges, docks, dams, etc.) and 

increased numbers of vessels in CI beluga habitat can potentially affect the distribution, 

migration, or behavior of CI belugas and their prey. However, a lack of understanding of 

distribution, migration, and behavior patterns of prey inhibits potential mitigation measures and 

argues for a more precautionary approach to maximize opportunity for CI beluga recovery. 

Additional information is needed on the impacts to CI belugas from construction and operation 

of physical structures, including structures located both within Cook Inlet proper and upstream of 

CI beluga habitat (which could affect beluga prey). Particular emphasis should be given to areas 

of known and historic feeding importance (e.g., Susitna River and Delta; Kenai River; Knik 

Arm).

40. Assess the biological benefits, costs, and implementation feasibility of potential protection or 

restoration measures for particular habitats important to CI beluga recovery and implement 

such measures if determined warranted.

Considering the ecological value, stability, and resiliency of habitats important for CI beluga 

recovery, including habitats that support foraging or reproduction, an analysis will be needed to 

determine if protection or restoration measures are warranted and whether previous mitigation 

measures may no longer be needed. Throughout the long term, a variety of potential mitigation 

measures may be applied, representing a range of likely outcomes for CI beluga habitat and 

future CI beluga recovery. An analysis must first be conducted to evaluate the costs, biological 

benefits, and implementation feasibility, of potential protection or restoration measures. For 

some potential measures, realistic benefits may be achieved at little cost, whereas other measures 

may be expensive to implement and are likely to offer questionable or limited positive results. 

Implementation of any protection or restoration measures must be accompanied by long-term 

monitoring to determine the effects on CI beluga recovery. Because CI beluga recovery is likely 

to be an ongoing process, the array of potential protection or restoration measures should be 

periodically examined and the implemented measures revised as needed.

41. Work with local, state, and federal agencies and stakeholders to develop a comprehensive 

Cook Inlet habitat database, and methods and plans for reducing or mitigating the levels of 

habitat loss or degradation in areas of known importance to CI belugas for foraging and 

reproduction, including restoration of habitats if necessary.

Ongoing and future coastal development projects that are deemed likely to degrade CI beluga 

habitat should be mitigated. Potential effects of individual development projects should be 

evaluated on the basis of the aggregate and comprehensive impacts on beluga habitat, taking into 

account existing projects and disturbance, and not simply as the incremental impact of an 

additional individual project. Such mitigation efforts will be most effective if they are developed 

collaboratively between government and non-government entities. For instance, collaborative 

work with municipalities or other entities could be undertaken to help minimize runoff and 

stormwater pollution and to reduce the incidence of toxic spills into Cook Inlet.
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VI-23

42. Identify potential likely sources of contamination and evaluate their potential to discharge 

contaminants.

Given the potential for adverse cumulative impacts on CI belugas from the multiple human 

activities occurring in Cook Inlet, it is important to have a detailed understanding of exactly 

where those activities are occurring, if activities involve contaminants of concern that may be 

purposefully or accidentally discharged, and the proximity across time or space to other 

activities. Although some individual discharges might be deemed insignificant, combinations of 

discharges, or discharges in combination with other dissimilar threats, could cause adverse 

effects at the individual and population levels. Although assessing cumulative impacts from 

multiple activities is challenging, such impacts might be particularly relevant in the case of CI 

belugas given the population’s failure to recover despite the curtailment of hunting. A 

comprehensive inventory or database should map the following: activities producing chemicals 

of concern; sites containing chemicals of concern; and other stressors with a potential synergism 

with chemicals (e.g., predators, noise; see Action 56). This inventory or database should be 

developed and updated annually.

Unauthorized Take

The full extent of unauthorized take is likely unknown, and activities that may result in injury 

or harassment of CI belugas may be under-reported. There is a need to assess if unauthorized 

take is limiting CI beluga recovery as a result of injury or harassment of CI belugas, especially in 

areas important to CI belugas for foraging or reproduction. To effectively manage the effects of 

this threat on CI beluga recovery, there is also a need to improve the understanding of the causes 

of unauthorized take in Cook Inlet and to improve management of activities that may result in

unauthorized take of CI belugas. Below are recommended actions to address this threat.

43. Review available data which may provide information about the types and level of 

unauthorized take in living and dead CI belugas to improve knowledge about the prevalence,

frequency, and severity of effects on CI belugas from these activities.

While infrequent, there has been evidence of unauthorized take of CI belugas in recent years.

There have been sporadic reports of CI beluga entanglements either in fishing gear or marine 

debris, photographic evidence of scars from boat propellers and possible bullet wounds, and 

necropsies documenting signs of blunt force trauma, possibly as a result of vessel strikes. In 

addition, there were possibly three research-induced CI beluga mortalities in 2002. Examples of 

other activities with potential to result in unauthorized take include recreational or sightseeing 

operations targeting CI belugas in a manner that causes a change in the behavior of the animals. 

However, there has been no systematic review of all available take-related information, 

especially for activities that are not the subject of specific regulatory or management reviews 

regarding effects on CI belugas, and for which there is no clear regulatory mechanism requiring 

reporting of take. This information should be reviewed and compiled to improve knowledge 

about the prevalence of the different types and levels of unauthorized take, and to determine the 

frequency and effects of this take on CI belugas.

44. Review and continue to monitor for signs of trauma in living and deceased CI belugas to 

assess the presence/absence of indications of trauma from entanglements or vessel strikes in 

living whales, and the percentage of necropsied CI belugas with mortalities attributed to or 

associated with anthropogenic trauma.
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In order to understand if unauthorized take is limiting the recovery of CI belugas, 

information is needed to determine the prevalence of signs of injury or trauma in living whales 

and the number of mortalities associated with anthropogenic activities (as determined via 

necropsy). For living whales, non-invasive methods such as a review of the photo-identification 

catalog should be employed to determine past signs of trauma, and can be used to continue to 

monitor signs in the future. This type of monitoring may also help determine the effects of any 

particular trauma to the individual whale. For deceased whales, necropsies will be necessary to 

determine if the cause of death is related to unauthorized take, and a review of past necropsy 

reports may help determine the percentage of whales suffering mortalities due to anthropogenic 

activities. These types of monitoring activities should be continued into the future to help 

determine if the levels and/or effects of this threat are changing over time.

45. Refine research techniques, evaluate alternatives, and implement research methods which 

minimize harassment, harm, and general adverse impacts on CI belugas. Only conduct 

research on CI belugas that has a clear connection to their recovery.

Research activities conducted in Cook Inlet have the potential to result in unanticipated 

mortalities or harassment of CI belugas. The potential impacts of various research methods (e.g., 

crossbow biopsy, breath analysis, live captures, and accessing live strandings) needs to be 

evaluated and the method with the least adverse impact to the animals should be used as much as 

possible. Existing and new research techniques and mitigation strategies should be reevaluated to 

minimize their impact. Minimally invasive techniques, such as collection of floating fecal or skin 

material, or well-designed skin/blubber biopsy surveys, should be given priority over more 

invasive methods with higher potential for harassment or harm (e.g., activities involving chase, 

or requiring capture of animals). For invasive research techniques, the use of surrogate sympatric 

species within Cook Inlet (harbor seal and/or harbor porpoise) and other healthy beluga 

populations should be considered for testing protocols and obtaining comparative data prior to 

use on CI belugas. Criteria to determine whether particular research methods should not be 

authorized need to be developed.

46. Evaluate the relative effect of different types of vessels and speed on CI belugas.

Vessel activity around whales needs to be monitored and evaluated to determine the relative 

effect of different types of vessels and traveling speed on CI beluga behavior as well as the 

potential for collision (indirect and direct effect). Efforts should be focused in areas of high 

vessel traffic, such as the Port of Anchorage, Cook Inlet shipping lanes, the Susitna Delta and the 

lower reaches of the Kenai River.

47. Work with local, state, and federal agencies and stakeholders to: 1) monitor vessel activity in 

areas of known importance to CI belugas for foraging and reproduction; 2) develop a 

cooperative program to reduce whale interactions with vessels and fisheries; and 3) develop 

methods and plans for reducing or mitigating the levels of entanglements, vessel strikes, or 

other sources of anthropogenic trauma for areas of critical importance to CI belugas for 

reproduction and foraging.

There are multiple photos of individual CI belugas with scars consistent with boat strike 

indicating direct impact, but the relative importance of the effect of boat-induced injury is poorly 

understood. Indirect impacts could include acoustic impacts, inhalation of harmful engine 

exhaust, and disruption of critical behavioral activities (e.g., foraging, breeding, and calving). 

Data on vessel traffic in Cook Inlet, monitoring of vessel activity, and consideration of the
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VI-25

development of regulations regarding vessel speed and route may be necessary. At a minimum, 

whale-safe boating recommendations should be developed that include advisories to forewarn 

operators of times and areas with heightened risk of CI beluga encounters. Boating guidelines 

based on observed effects of boating on belugas and knowledge of preferred beluga habitat 

should be developed to minimize interactions (e.g., reduced speed areas and temporal and spatial 

restrictions to traffic).

Catastrophic Events

Catastrophic events have the potential to affect a large portion of the CI beluga population, 

and are considered a threat of high relative concern. To fully understand if catastrophic events 

are limiting CI beluga recovery as a result of injuries or mortalities, especially in areas important 

to CI belugas for foraging or reproduction, there is a need to improve the understanding of the 

causes and sources of catastrophic events; to include potential effects on CI belugas; and to 

improve the management of the causes, responses to, and prevention of catastrophic events 

resulting in injuries or mortalities of CI belugas. Below are recommended actions to address this 

threat.

48. Using currently available information, conduct a retrospective spatial and temporal 

evaluation of known catastrophic events in Cook Inlet since the 1970s, and assess if there are 

changes in the frequency, distribution, or types of catastrophic events over time.

Currently there is no single place to obtain information about catastrophic events in Cook 

Inlet (e.g., natural disasters, oil spills, mass CI beluga strandings, key prey run declines, etc.) and 

no assessment conducted to determine if the frequency, distribution, or types of catastrophic 

events are changing over time or are influencing the CI beluga population. As such, an analysis 

needs to be conducted examining the available information regarding catastrophic events in 

Cook Inlet since the 1970s to determine if the frequency, magnitude, or severity of these events 

is changing over time. Such changes, especially in important CI beluga foraging or reproduction 

areas, could indicate that this type of threat may have greater impacts to CI beluga recovery.

49. Review catastrophic events in areas known to be important to CI belugas for foraging or 

reproduction and assess if a correlation exists with CI beluga distribution, abundance, or 

reported mortalities that may suggest catastrophic events are limiting recovery.

Catastrophic events have resulted in adverse effects on other cetaceans (e.g., killer whale 

mortalities after the Exxon Valdez oil spill), but with the exception of information about CI 

beluga mass strandings, there has been no comprehensive review of catastrophic events in Cook 

Inlet. While the effects of catastrophic events are variable, population modeling indicates that 

any additive mortality of CI belugas will have a significant negative effect to the recovery 

potential of these whales. Non-stranding related catastrophic events that occur in areas known to 

be important to CI belugas for foraging, reproduction, or where large groups of belugas

congregate (e.g., Susitna Delta) have a greater potential for negative effects on the whales than 

do catastrophic events in areas less frequently used by belugas or occupied by only a small 

number of belugas at a given time (e.g., areas south of the Forelands during summer). Therefore, 

to restrict the spatial extent of this action to the most important areas with the greatest potential 

for adverse effects, an analysis should examine if a correlation exists between catastrophic events 

north of the Forelands and CI beluga distribution, abundance, and reported mortalities.
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VI-26

50. Conduct a retrospective analysis of documented CI beluga live strandings and catastrophic 

events in Cook Inlet and assess if a correlation exists which may indicate catastrophic events 

are limiting recovery by causing mass strandings.

The causes of live mass strandings of CI belugas are not clearly known, and may result from 

a variety of factors including tidal stage or the presence of predators in the vicinity. However, it 

is also possible that catastrophic events may also lead to mass strandings for reasons unknown.

Although the reasons may not be clear, it is clear that some animals are found dead after a mass 

stranding. Thus, even if a catastrophic event itself does not directly lead to mortality, if that event 

leads to a mass stranding, the potential for mortality increases. Loss of individuals from the 

population has the greatest immediate effect to the recovery potential of the population. A 

retrospective analysis examining a correlation between catastrophic events and mass strandings 

may help determine if catastrophic events are limiting CI beluga recovery.

51. Review available data which may provide information about mortality rates (e.g., CI beluga 

stranding records) and assess if the occurrence of mortality is correlated with known 

catastrophic events.

Given that additive mortalities reduce the recovery potential of CI belugas, any additive 

mortalities associated with catastrophic events must limit CI beluga recovery. The information 

obtained from Actions 48–50 should provide the basis for a review to determine if catastrophic 

events are limiting CI beluga recovery by resulting in increased mortalities.

52. Assess CI belugas for signs of catastrophe-induced distress to determine whether mortalities 

or reduced fitness can be directly or indirectly attributed to catastrophes.

Although mortalities have the most immediate effect to recovery, catastrophic events that 

lead to injuries and reduced health or fitness can lead to reduced recovery potential for the 

population. In anticipation of future catastrophic events, actions should be taken to monitor CI 

belugas, via non-invasive methods, for signs of distress which may indicate compromised health.

Any mortalities in the months following a catastrophic event should undergo a thorough 

necropsy to assess if the catastrophic event contributed to the cause of death. Results from 

examinations of dead CI belugas should be linked with the CI beluga photo-identification 

catalog, if possible. If there is sufficient available information from previous catastrophic events, 

that information should be considered when determining if catastrophic events are limiting CI 

beluga recovery.

53. Review and update oil and hazardous substance spill response plans to minimize effects of 

spills on CI belugas, including strategies to deter CI belugas from entering oiled areas.

NMFS should work with the U.S. Coast Guard and industry groups to develop and test 

wildlife response plans and to acquire and maintain the necessary equipment and supplies to 

deter belugas from entering oiled and/or contaminated habitat, move animals back out of oiled 

and/or contaminated habitat should they enter it, and monitor, and if necessary, rehabilitate 

belugas directly impacted by an oil or hazardous substance spill.

54. Evaluate and test deterrent or hazing strategies aimed at preventing belugas from entering 

specific areas of concern.

When responding to an oil or chemical spill, primary strategies focus on spill containment. 

Secondary strategies seek to prevent wildlife from entering areas affected by the spill and 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-27

dispersants. Such secondary strategies may also be potentially useful for deterring CI belugas 

from using areas with a high risk of live stranding. Various hazing methods have been used 

successfully with other marine mammals but have not been evaluated for use on belugas. Their 

routine exposure to high ambient noise and boat traffic may make CI belugas more resistant to 

acoustic techniques used to deter other species or populations. Existing techniques should be 

evaluated for deterring belugas from specific areas of concern, preferably using other (non-CI) 

beluga populations. 

55. Hold annual drills to respond to belugas impacted by catastrophic events.

Plans are only as effective as the training and preparedness of those who execute those plans. 

While the risk of an accidental discharge of a hazardous substance from any single 

anthropogenic activity is considered to be low, the probability of a toxic spill increases with the 

number of anthropogenic activities, increasing the potential for catastrophic loss of CI belugas. 

Therefore, it is important to develop plans to respond to incapacitated belugas involved in such 

an event and to train and rehearse for actual responses. Such training and drills should be 

combined with drills to respond to live strandings due to natural causes.

The development of methods to support whales that have live-stranded and better monitor 

their disposition could help to reduce mortality and enhance recovery. As such, regular trainings 

and drills for live stranding responses should be conducted to maintain skills of responders to 

provide supportive care to the whales during live stranding events. During such trainings and 

drills, stranding response kits that include cameras and measuring, recording, and sampling 

equipment should be distributed.

Cumulative Effects of Multiple Stressors

Cumulative effects of multiple stressors are considered to be a high concern for the recovery 

of CI belugas. In the absence of a single threat clearly limiting recovery, the cumulative effects 

(including any synergistic effects) from multiple stressors limiting recovery is a most plausible 

explanation for why the CI beluga population has not recovered.

The compounded effect of multiple stressors in constraining CI beluga recovery can be 

greater than the effect of any single stressor or sum of stressors. Thus, recovery actions to 

address cumulative effects of multiple stressors require a complex approach. A first step is to 

identify single factors contributing to stress, followed by the identification of additive 

accumulation of stress (cumulative impacts), including interactions between factors that produce 

a combined effect greater than the sum of their separate effects (synergisms). Following 

identification of these components of multiple stress factors, mitigation measures can be 

identified and potentially implemented. Identifying and monitoring cumulative effects will 

depend on accumulation of individual beluga life-history data and associated environmental data;

in addition, this will depend on the analyses of these data using the techniques of epidemiology 

and population modeling to identify and characterize the population level impact of these effects.

Improvements in the understanding of the causes, relationships, and impacts of cumulative 

effects on CI belugas can also contribute to improvements in management of the causes and 

prevention of cumulative effects on CI belugas. Below are recommended recovery actions to 

address cumulative effects.

56. Conduct a temporal and spatial analysis of all types and sources of threats to CI belugas, 

documenting times and areas where threats overlap, and assess if a correlation exists with 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-28

CI beluga abundance or distribution which may suggest the effects of multiple stressors are 

limiting CI beluga recovery.

CI belugas exist in a dynamic environment, in which specific conditions may persist 

throughout the year, may occur seasonally over a series of years, or may occur infrequently over 

an indeterminate time frame. The identification of potential multiple or cumulative effects that 

may have constrained productivity or recovery of CI belugas will help to identify factors that 

may be critical to CI beluga recovery in the future. These factors may become important due to 

short or long-term changes in ecological, environmental, or anthropogenic conditions, and may 

also operate across changing spatial scales. Evaluation of changes and subsequent impacts on CI 

beluga recovery will need to consider both sequential effects and co-occurring factors. There is a 

need for coordinated spatial and temporal analyses of how natural and anthropogenic stressors 

influence beluga habitat use. On a single day, a single beluga moving through Cook Inlet may be 

exposed to multiple stressors from multiple sources, and the course of a beluga lifetime may 

encompass exposure to threats from numerous natural and anthropogenic stressors.

Threats identified in this recovery plan should be analyzed both independently and 

cumulatively. This may require the generation of a comprehensive, geospatial database of past 

and present anthropogenic activities (e.g., development, industry, transportation, military, and 

research projects) in Cook Inlet. CI belugas are exposed to many threats and the risk of 

accumulation of negative effects is high. Increasing the number of threat sources also increases 

the probability for synergistic effects to occur. Because exposure could occur during a given time 

period (e.g., summer) or in specific areas (e.g., near Anchorage), a temporal and spatial analysis 

of the distribution of all the threats would allow identification of peak periods or areas of higher 

risk of cumulative effects. Furthermore, movements of CI belugas throughout the Inlet are not 

random, but are driven by tide cycles, the seasonal presence of beluga prey, and winter ice. If 

temporal presence of threats in different areas overlaps with CI beluga movement patterns (i.e., 

belugas move among areas but encounter different threats in each area), impacts could 

accumulate with spatial overlap. Similarly, cumulative effects could derive from the exposure to 

multiple stressors accumulated within a specific time period or in a specific area.

For example, information regarding the types of anthropogenic activities known to introduce 

acoustic energy into the water, the timing and location of these energy sources, any mitigation 

applied, and acoustic characteristics should be logged into a database to track all potential noise 

stressors and their temporal and spatial coverage. These data should be linked to the NMFS CI 

beluga stranding database to allow detection of potential relationships between anthropogenic 

noise events and strandings. This open-access database should be developed, maintained, and 

managed by NMFS, with contributions from university, private, agency, and industry researchers 

in Cook Inlet.

Analyses of identified threats in a geographic information system (GIS) format would help 

determine spatial and temporal associations and overlaps. For example, patterns in historical or 

prolonged coastal or upstream development could be identified as a combination of factors 

associated with anthropogenic development. Such overlaps could be examined for correlations to 

changes in CI beluga distribution patterns to better understand factors with the greatest potential 

to impact CI beluga recovery.

57. Conduct a meta-analysis of previously documented cumulative effects for other populations 

and species, based on known threats for CI belugas, and prioritize risk to CI belugas based 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-29

on how these threats have been shown to negatively affect other beluga populations, other 

odontocetes, or other marine mammals.

Because many potential factors may be impeding CI beluga recovery, it is important to 

narrow the list by identifying spurious correlations (e.g., haphazard or non-causal relationships) 

between given factors and a lack of recovery. Available data on potential cumulative factors are 

often limited, so an initial step would be to examine historical data from other marine mammal 

populations. Such research would require a meta-analysis of available data, prioritized to focus 

first on other beluga populations, then other odontocetes, then other cetaceans, and, finally, other 

marine mammal populations.

Based on results of the meta-analysis described above, the next step would be to evaluate 

whether the combinations of threats found to be constraining productivity in other marine 

mammal populations might be similarly impeding the recovery of CI belugas. This step would 

require characterization of potential threats in Cook Inlet such that co-occurrences of these 

threats in time, space, or both may be examined.

58. Analyze the potential synergism among noise exposure, chemical pollutants, and potential 

predation to identify if there are activities, locations, or periods of time for which CI belugas 

may be at high risk for synergistic effects.

It has been shown in other vertebrates that even weak stressors, when combined with other 

equally weak though dissimilar stressors, can have negative, synergistic impacts on reproduction 

and survival. Synergistic effects have not been studied for cetaceans, but there is evidence in 

other species of synergism associated with noise in combination with the presence of chemical 

pollutants and predators. All these factors are present in CI beluga habitat. By analyzing the 

potential synergism among noise exposure, chemical pollutants, and potential predation in CI 

belugas, specific locations, time periods, and certain human activities could result in unexpected 

severe threats because of synergism with other concurrent or sequential threats.

59. Review the CI beluga stranding records for co-occurrence of multiple stressors.

To date, the CI beluga stranding database has been examined to only a limited extent for the 

primary factors potentially related to observed CI beluga strandings. Additional information may 

be extrapolated from the CI beluga stranding database by reviewing stranding records for 

indications of multiple or secondary factors such as gunshot or propeller wounds, poor body 

condition (e.g., little blubber, muscle atrophy, etc.). Such an analysis would facilitate a better 

understanding of the prevalence of multiple stressors and the contribution of co-occurring 

stressors to overall CI beluga mortality.

60. Evaluate sequential effects compared to effects of multiple co-occurring stressors.

Evaluations of the effects of multiple stressors on organisms have often focused on factors 

that occur simultaneously. However, the aspect of latent effects due to sequential, but not cooccurring, stressors is often difficult to evaluate. The results from the meta-analysis of potential 

threats in CI beluga (see Action 57) and related species will provide guidance on sequential 

factors that may be detrimental to CI beluga recovery.

61. Develop a PVA model component to incorporate covariance effects of multiple stressors.

The current approach for predicting trends in CI beluga abundance is through a PVA model. 

The PVA population model should be: transparent, publicly available, and well documented with 
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-30

meta-data embedded in its code or as a separate document. It should include risk of cumulative 

stressors impacting individual survival or reproduction. This could then be used to evaluate the 

potential interaction of multiple stress factors, and their impacts on the risk of extinction and 

potential for recovery of the population.

62. Review the current system for allocation of takes (by harassment) of CI belugas to see if a 

comprehensive approach, rather than by individual project, increases managers’ ability to

reduce the cumulative effects of harassment takes by numerous projects.

Although individual activities might be deemed insignificant when considered independently, 

creeping normality30 (e.g., death by a thousand cuts) can cause substantial adverse effects to

nearly any entity, including CI belugas, at both individual and population levels. Applications for 

Incidental Harassment Authorizations (IHAs) historically have been reviewed on the basis of an 

individual activity in isolation. But the high level of human activity in Cook Inlet has increased 

such that cumulative effects of multiple activities must be appropriately accounted for. Although 

assessing cumulative impacts from multiple activities is challenging, results of such an 

assessment might be particularly relevant for understanding the lack of recovery for CI belugas. 

A framework should be developed by NMFS for assessing cumulative impacts to belugas from 

the numerous activities occurring in Cook Inlet.

In 2012, the CI beluga population was estimated at 312 whales, and over 2,700 takes were 

requested for research and development projects (NMFS, unpub. data). To monitor how many 

allocated takes are actually used (as opposed to how many takes are granted), the process for 

reporting takes needs to be streamlined and expedited. For example, research takes occurring in 

the summer are not required to be reported until fall of the following year. Requiring more 

frequent reporting of takes and better tracking of take will better inform NMFS of how many 

takes are actually occurring, and will allow better take allocation in subsequent years. However, 

this process will not account for take by activities that either do not properly report take or that

do not undergo review by NMFS to authorize take.

In the future, NMFS could also establish a limit for annual takes granted to development 

projects, research projects, and all projects combined. The total allocated take could be capped 

annually at some fraction of the population estimate from the previous year. 

63. Encourage the resources users/development community in Cook Inlet to create a joint 

industry program to gather and compile data to share for consultation, permitting, and 

mitigation processes, and to fund research to improve mitigation of impacts on CI belugas 

and their habitat.

Individually, several development projects in Cook Inlet have conducted a variety of studies 

to define baselines for the distribution, abundance, and habitat use of CI belugas in project areas. 

Many of these areas are within CI beluga critical habitat. In some cases, study results have been 

made public, but others remain proprietary. The E&P Sound and Marine Life Joint Industry 

Programme31 (JIP) is used elsewhere by the oil and gas industry to direct research that will help 

 

30 Creeping Normality: the way a major negative change, which happens slowly in many unnoticed increments, is not perceived 

as objectionable. For more information about the concept of creeping normality, see the book “Collapse: How Societies 

Choose to Fail or Succeed” by Jared Diamond.

31 The E&P Sound and Marine Life Joint Industry Programme website can be found at: http://www.soundandmarinelife.org/
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-31

industry and managers identify effective and efficient mitigation measures for oil and gas

development, and may be a useful model for all development projects (not just the oil and gas 

industry) in Cook Inlet. Such a coalition would allow participants to pool their administrative 

resources and efficiently focus their efforts on environmentally responsible development that 

will not impede the recovery of CI belugas.

64. Consider analysis of results for cumulative effects of multiple stressors to update regulations.

Regulations should not only consider the noise type and overall levels introduced into CI 

beluga habitat by each activity independently, but also the potential effects of different stressors 

(acoustic and non-acoustic) occurring concurrently or sequentially over time or space. Research 

results on cumulative (including synergistic effects) could inform appropriate revisions to 

existing regulations that would improve management of acoustic impacts to CI belugas.
Cook Inlet Beluga Whale VI. RECOMMENDED RECOVERY ACTIONS

Recovery Plan A. Recovery Actions and Narrative

VI-32

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Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-1

VII. IMPLEMENTATION SCHEDULE

The Implementation Schedule that follows outlines actions and estimated costs for the 

recovery program for CI belugas as set forth in this recovery plan. It is a guide for meeting the 

recovery goals outlined in the plan. This schedule indicates action numbers, action descriptions, 

recovery priorities, the potential parties responsible for actions (either funding or carrying out), 

duration of actions, and estimated costs. 

Priority: Priorities are assigned to each action in the Implementation Schedule. Assigning 

priorities does not imply that some recovery actions are of low importance; instead it implies 

they may be deferred while higher priority recovery actions are being implemented. It is 

important to remember that we have focused this section only on the threats identified as of 

medium or high relative concern.

• Priority 1 – Actions that must be taken to prevent extinction or to prevent the species 

from declining irreversibly.

• Priority 2 – Actions that must be taken to prevent a significant decline in species 

population/habitat quality or in some other significant negative impact short of extinction.

• Priority 3 – All other actions necessary to provide for full recovery of the species.

The definitions for priority 1, 2, and 3 are defined in the Endangered and Threatened Species 

Listing and Recovery Priority Guidelines (55 FR 24296, June 15, 1990) developed by NMFS.

Based on these definitions and based on the fact that we do not know which threats are

preventing CI belugas from recovering to the point where they are not in danger of becoming 

extinct in the foreseeable future, there are few priority 1 actions in this plan. We have limited 

priority 1 actions to those associated with monitoring the population’s status since doing so is 

crucial to determine the effectiveness of this recovery plan. As the results of research and 

reassessments become available, we recognize the levels of concern for the threats, as well as the 

priorities, may change. This plan is meant to be adaptive to allow for such changes.

Potential Responsible Parties: The group(s) identified as “Potential Responsible Parties” 

have been identified as the best lead party/parties to implement discrete recovery actions. When 

more than one party has been identified, the proposed lead party is listed first. Many lead parties

are agencies or organizations with authority, responsibility, or expressed interest to implement a 

specific conservation action. Inclusion as a Responsible Party does not commit any entity to 

taking action. Rather, it conveys who may be best suited for completing the action. The listing of 

a party in the Implementation Schedule does not require the identified party to implement or 

fund the implementation of any action. 

Estimated Costs and Duration: Costs are estimated for the fiscal year in thousands of 2016-

value U.S. dollars ($K) and are not adjusted for inflation. Estimates of costs were derived from a 

variety of sources, including government agencies and other organizations. Tabular cost 

estimates do not imply that funding will be available for accomplishing that recovery task. Costs 

were estimated in accordance with the number of years necessary to complete the task once 

implementation has begun. The table below covers a five-year period, in accordance with the 

standard five-year cycle of review and update/revision for all recovery plans. 

The total time and cost to recovery are very difficult to predict with the current information, 

and the total cost to recovery will be largely dependent upon the number of threats management 
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-2

actions requiring implementation. Since that cannot be determined prior to implementation of 

portions of this plan, the total cost presented here assumes implementation of all recovery 

actions. Thus, we expect the total estimated cost to achieve recovery presented here is high;

actual costs will be lower if actions addressing some threats are not implemented because those 

threats have been determined not to be limiting the recovery of CI belugas. It is expected that 

recovery may take at least two generations (50 years); therefore, for ongoing actions costs have 

only been given for the next 50 years. If every identified recovery action must be implemented, 

and if it takes 50 years to recover CI belugas, then the estimated cost of implementing this entire 

recovery program is approximately $76.8 million.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-3

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

POPULATION MONITORING, RECOVERY PLAN IMPLEMENTATION, AND EDUCATION/OUTREACH ACTIONS:

1. Continue to conduct 

surveys to estimate 

abundance, and analyze 

population trends, calving 

rates, and distribution.

1 NMFS, 

LGL

500 200 500 200 500 ongoing 17500 Currently, NMFS 

conducts biennial 

aerial surveys for 

population estimate 

purposes (began in 

1993), and LGL 

conducts annual 

photo-identification 

studies (began in 

2005).

2. Create and support a CI

Beluga Recovery 

Coordinator position.

1 NMFS 150 150 150 150 150 ongoing 7500 This estimate includes 

fringe benefits as well 

as salary.

3. Create and support a CI 

Beluga Recovery 

Implementation Task 

Force.

1 NMFS 50 50 50 50 50 ongoing 2500

4. Increase efforts to identify 

and monitor individual CI 

belugas, coordinating 

photo-identification, 

stranding data, genetic

studies, and body 

condition assessments via 

biopsy samples of skin 

and blubber.

2 NMFS,

ADFG,

LGL

0 100 0 0 0 once, with 

updates 

every 5 

years

325 This effort is targeted 

at compiling different 

datasets and does not 

include data collection.

The initial effort is 

likely to be more 

costly than subsequent 

updates (estimated at 

$25K). Results to be 

integrated into annual 

reviews and 

coordination meetings 

per Action 7.

5. Determine annual 

mortality and reproductive 

rates of CI belugas.

2 NMFS, 

AVPS, 

ASLC

0 0 0 0 0 ongoing 0 Costs associated with 

this effort are 

incorporated into other 

actions (e.g., Actions 

1, 7, 16, 24).
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-4

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

6. Conduct regular biopsy 

surveys of CI belugas to 

monitor changes in 

condition and reproductive 

success in relation to 

environmental changes.

2 NMFS,

ADFG

300 300 300 300 300 yearly for 5 

years, then

once every 5 

years

2700 Biopsy surveys during 

the first five years will 

build the dataset and 

allow for initial 

analyses, with 

subsequent surveys 

allowing for 

population monitoring.

7. Organize an annual review 

and coordination 

workshop to review 

existing data on individual 

CI belugas, plan 

expansion of future data 

collection and analyses, 

and facilitate linkage of all 

existing and new CI 

beluga-related research.

1 NMFS 50 50 50 50 50 yearly 2500 All new information 

from other recovery 

actions should be 

shared during these 

annual meetings.

8. Hold a workshop to 

consider the feasibility, 

risks, and benefits of 

different sampling 

techniques such as breath 

capture, remote 

ultrasound, and live 

captures to obtain samples 

and measures for further 

analyses.

3 NMFS 50 0 0 0 0 once 50 In April 2014, NMFS 

hosted a workshop of 

experts in the field of 

biopsy. The workshop 

report is recommended 

for use in planning any 

biopsy-related study, 

and is available on the 

NMFS AKR website.

9. Conduct a workshop to 

update a model to 

determine the probability 

of extinction of CI 

belugas.

2 NMFS 75 0 0 0 0 once every 5 

years

750 This may be a single 

workshop, or a series 

of workshops held 

within the same year.

10. Engage in education and outreach efforts targeted at informing the public of the status of CI belugas and their threats, and promoting more public involvement in 

reporting CI belugas.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-5

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

10a. Provide information 

regarding threats to CI 

belugas and ways the 

public can help mitigate 

those threats.

3 NMFS 1 1 1 1 1 ongoing 50 Could be organized 

and supported by the 

NMFS CI Beluga 

Recovery Coordinator 

(Action 2); and 

implemented as part of 

ongoing management 

processes or in 

association with other 

workshops. Nominal 

costs associated with 

outreach activities are 

identified.

10b.

Develop and broadcast 

annual announcements 

promoting the use of 

citizen science and 

encouraging reporting of 

strandings and sightings 

by the public.

3 NMFS 5 5 5 5 5 yearly 250 Could be organized 

and supported by the 

NMFS CI Beluga 

Recovery Coordinator 

(Action 2); 

implemented as part of 

ongoing management 

processes or in 

association with other 

workshops.

10c. Create an annual Cook 

Inlet Beluga Watch Day.

3 NMFS, 

ADFG, 

NGO,

ASLC,

DOW

25 25 25 25 25 yearly 1250

11. Improve the stranding 

response program for both 

live and dead CI belugas.

2 NMFS,

ASLC,

AVPS,

other CI 

beluga 

stranding 

partners

0 50 50 50 50 yearly 2450
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-6

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

12. Once every five years, 

reassess the status of the 

CI beluga population and 

each of the threats to CI 

belugas.

2 NMFS 0 0 0 0 500 once every 5 

years

5000 These should be 

reviewed in 

association with the 5-

year status reviews.

THREATS MANAGEMENT ACTIONS:

REDUCTION IN PREY

13.. Evaluate how prey 

abundance and availability 

has changed over time in 

comparison to CI beluga 

abundance and if there are 

direct correlations 

between the two 

suggestive of a positive 

link between prey 

abundance or availability 

and CI beluga abundance, 

productivity, or mortality.

2 NMFS, 

ADFG

80 0 0 0 0 once every 5 

years

800

14. Monitor body condition of 

living and deceased CI 

belugas to assess the 

presence/absence of 

nutritional distress or 

nutritional-related 

mortalities, and determine

the percentage of 

necropsied CI belugas 

with mortalities attributed 

to nutritional distress.

2 NMFS, 

LGL, 

ASLC, 

AVPS

30 0 0 0 0 once every 5 

years

300 Much of the costs for 

collecting this 

information are 

associated with other 

actions, notably 

stranding response and 

photo-identification 

efforts.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-7

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

15. Analyze the existing 

collection of CI beluga 

teeth to determine if age at 

first reproduction for 

female CI belugas can be 

determined, and assess if 

there has been a 

significant change in this 

parameter over time.

2 NMFS, 

ADFG, 

UA

40 0 0 0 0 once every 5 

years

400 NMFS will need to be 

contacted regarding 

access to the teeth 

collected from dead 

belugas.

16.

Review available data 

which may provide 

information about calving 

rate (population-wide) or 

calving interval

(individual belugas), and 

assess whether either of 

these parameters is

correlated with prey 

abundance.

2 NMFS, 

LGL

50 0 0 0 0 once every 5 

years

500 NMFS has some data 

available from 

previous aerial surveys 

in August looking at a 

calving index. Longterm photoidentification studies 

may provide 

information useful in 

the assessment of 

calving rates/intervals.

17. Research the seasonal,

spatial, and size variation 

in prey diversity and 

quality to improve 

assessments of 

relationships between CI 

belugas and their prey.

2 NMFS, 

ADFG, 

UA

0 300 300 300 300 yearly for 5 

years, then

once every 5 

years

4200

18. Research the effects of 

environmental and 

anthropogenic factors on 

CI beluga prey to assess if 

any particular factor is 

having a significant 

detrimental effect to the 

prey and thus a 

detrimental effect on CI 

beluga recovery.

2 NMFS, 

ADFG, 

UA, 

CIRCAC

0 70 70 70 70 yearly for 5 

years, then 

once every 5 

years 

910 Supplemental to 

Action 17; partly 

implemented as part of 

Noise actions.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-8

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

19. Determine energetic 

requirements/metabolic 

needs of CI belugas at 

different life stages to 

determine whether 

nutritional stress is a 

function of life stage.

2 ADFG, 

UA, 

NMFS, 

ASLC, 

APU

0 150 150 0 0 2 years 300 Study Cook Inlet and 

Bristol Bay belugas, 

and potentially captive 

belugas in aquaria, in 

conjunction with other 

projects.

20. Study the diet selectivity 

of different CI beluga 

demographic groups (e.g., 

age, sex, and reproductive 

state).

2 ADFG, 

NMFS, 

UA, APU

0 100 100 50 50 4 years 300 Consider aquaria 

studies.

21. Using currently available 

information, develop a CI 

beluga foraging model 

informed by prey 

characteristics and beluga 

dietary needs.

2 NMFS, 

UA, 

ADFG, 

APU

0 0 0 60 0 once, with 

updates 

every 5 

years

330 The initial effort is 

likely to be more 

costly than subsequent 

updates (estimated at 

$30K).

22. Ensure fisheries 

management (e.g., 

escapement goals for CI 

beluga prey species) 

adequately accommodates

CI beluga prey

requirements, and if 

necessary, expand the 

number of species with 

escapement goals.

2 ADFG, 

NMFS

0 0 0 0 0 5 years 0 Implemented as part of 

ongoing management 

processes; assumes no 

additional costs.

DISEASE AGENTS
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-9

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

23. Analyze images from the 

CI beluga photoidentification catalog for 

the presence of external 

signs of disease in 

photographically 

identified CI belugas to 1) 

assess the percentage of 

identified CI belugas with 

external indications of 

disease, and 2) track the 

persistence of, or changes 

in, the external indications 

of the disease agent in 

individual whales over 

time.

2 NMFS, 

ASLC, 

AVPS, 

LGL

50 0 0 0 0 once every 5 

years 

500 Costs also include 

analyses for action.

24. Continue examining 

beach-cast carcasses of CI 

belugas for disease-related 

mortalities, assessing the 

percentage of necropsied 

CI belugas with 

mortalities attributed to 

disease agents, and linking 

results from examinations 

of known individual 

belugas with the CI beluga 

photo-identification 

catalog. When feasible, 

determine the presence 

and relevance of disease 

agents in other Cook Inlet 

marine mammal 

mortalities.

2 NMFS, 

ASLC, 

AVPS, 

LGL

8 8 8 8 8 ongoing 400 NMFS already 

provides separate 

funding to specific 

Marine Mammal 

Stranding Network 

responders for 

necropsies; photoidentification 

component associated 

with Action 23; 

linkage of results can 

be associated and 

incorporated in Action 

7.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-10

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

25. Using currently available 

information, compare data 

on diseases from CI 

belugas with other beluga 

populations to determine 

if there are abnormal 

levels or atypical types of 

disease agents present in 

Cook Inlet affecting CI 

belugas.

2 NMFS, 

AVPS, 

ASLC

15 0 0 0 0 once every 5 

years

150

26.

Determine types and 

sources of disease agents 

identified to be of concern 

specifically to CI belugas 

and assess management 

actions targeted at 

mitigating the disease 

agents.

2 NMFS 0 10 0 10 0 every other 

year

250

NOISE

27. Conduct a retrospective 

analysis of documented CI 

beluga live strandings and 

noise-producing 

anthropogenic activities in 

Cook Inlet, possibly to 

include the development 

of a database of 

anthropogenic activities 

that introduce noise to 

Cook Inlet, and assess if a 

correlation exists which 

may indicate noise is 

limiting CI beluga 

recovery.

2 NMFS 250 once with 

updates 

every 5 

years

700 Year 1 funds include 

the development of the 

anthropogenic 

activities database, 

linkage of that dataset 

to the NMFS stranding 

database (which is 

being finalized and 

available on the NMFS 

AKR website soon), 

and for conducting the 

retrospective analysis.

The funds for the 5 

year updates ($50K

each) include costs for 

updating the database 

with new data and 

updating the analysis.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-11

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

28. Conduct a retrospective 

analysis of anthropogenic 

noise-producing activities 

in Cook Inlet and 

information on CI 

belugas’ behavior and 

distribution to assess if a 

correlation exists that may 

indicate noise is limiting 

CI beluga recovery.

2 NMFS, 

ADFG, 

CIBA

0 75 0 0 0 once with 

updates 

every 5 

years

525 This action’s funding 

is for the initial

retrospective analysis

estimated at $75K, 

with 5-year updates 

estimated at $50K 

each.

29. Within areas designated as 

critical habitat Type 1, 

determine areas with high 

vs. low levels of 

anthropogenic noise, if 

there are significant 

typical changes (e.g., 

seasonal differences) in 

the levels of overall 

(natural plus 

anthropogenic) noise in 

that area, and assess if a 

correlation exists between 

CI beluga use of the area 

and the noise levels in the 

area.

2 NMFS, 

ADFG, 

CIBA

250 0 0 0 0 once with 

updates 

every 5 

years

1600 Five-year updates are 

estimated at $150K 

each.

30. Describe the acoustic 

characteristics of different 

anthropogenic noise 

sources in Cook Inlet and 

rate the potential acoustic 

impacts from each type of 

noise source on CI 

belugas.

2 NMFS, 

ADFG, 

CIBA

0 300 0 0 0 once every 

10 years

1500 Costs associated with 

data collection are 

mostly captured in 

Action 31. These costs 

include data analysis 

and rating the potential 

impacts to CI belugas.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-12

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

31. Conduct long-term and 

year-round monitoring of 

natural and anthropogenic 

noise (level and spectrum) 

in key areas where CI 

belugas currently and 

historically concentrated 

(including CI beluga 

critical habitat) to 

characterize and monitor 

the acoustic environment 

and identify sources, 

levels, and types of 

anthropogenic noise.

2 NMFS, 

ADFG, 

CIBA

0 600 600 600 600 5 years 3000 The costs presented for 

data collection in this 

action supplement 

Action 30.

32. Work with local, state, and 

federal agencies and 

stakeholders to develop 

methods and plans for 

reducing or mitigating the 

levels of anthropogenic 

noises in Cook Inlet, 

including incorporation of 

pre- and post-activity 

surveys for major noiseproducing activities to 

monitor CI beluga 

presence.

2 NMFS, 

ADFG

0 85 0 0 0 once every 5 

years

850 Costs depend on each 

activity to be 

monitored/mitigated; 

these costs assume 

logistics of working 

with all pertinent 

agencies and 

stakeholders to 

develop methods and 

plans.

33. Develop and incorporate 

into the noise 

monitoring/mitigation 

plans a protocol to identify 

the onset (received levels 

and distance) of CI beluga 

behavioral reactions to 

specific activities.

2 NMFS, 

CIBA

255 255 255 255 0 4 years 1020

HABITAT LOSS OR DEGRADATION
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-13

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

34. Develop a comprehensive 

Cook Inlet environmental 

database using currently 

available information to 

conduct a retrospective 

spatial and temporal 

evaluation of the 

biological, physical, and 

anthropogenic features in 

CI beluga habitat since the 

1970s and assess how the 

habitat has changed over 

time, including likely 

causes of change.

2 NMFS, 

ADFG, 

ADEC, 

ADNR, 

UAF

400 0 0 0 0 once every 5 

years

850 Year 1 funds include 

the development of the 

environmental 

database and for 

conducting the 

retrospective analysis.

The funds for the 5 

year updates ($50K

each) include costs for 

updating the database 

with new data and 

updating the analysis.

35. Compare the changes in 

habitat availability or 

quantity over time with 

changes in CI beluga 

distribution and 

abundance over time to 

assess if a correlation 

exists which may suggest 

habitat loss or degradation 

is limiting the recovery of 

CI belugas.

2 NMFS, 

ADEC, 

CIK, 

DOW

85 0 0 0 0 once every 5 

years

850

36. Review losses or 

degradation of habitats in 

areas known to be 

important to CI belugas 

for foraging or 

reproduction, and assess if 

a correlation exists 

between habitat changes 

and changes in CI beluga 

use of the area, possibly 

indicating that habitat loss 

or degradation is limiting 

the recovery of CI 

belugas.

2 NMFS, 

ADEC, 

CIK, 

DOW 

85 0 0 0 0 once every 5 

years

850
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-14

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

37. Update the comprehensive 

Cook Inlet environmental 

database developed in 

Action 34 and project the 

future extent and quality 

of CI beluga habitat.

2 NMFS, 

UAF, 

ADEC

0 0 50 50 20 3 years 120 Will require data 

acquisition through 

other action items, 

coupled with 

predictive modeling.

38. Conduct a detailed habitat 

survey to begin long-term 

habitat monitoring (quality 

and quantity), including 

the use of volunteers and 

community members.

2 NMFS, 

ADFG, 

UAF, 

NGOs, 

CIRCAC

0 0 125 125 125 5 years 625 Supplemental to

Action 34 by focusing 

on habitat 

characteristics. Could 

be organized and 

supported by the 

NMFS Cook Inlet 

Beluga Recovery 

Coordinator (Action 

2).

39. Evaluate impacts on CI 

belugas from 

anthropogenic activities 

with potential to result in

degradation or loss of CI 

beluga habitat, with 

emphasis in known and 

historic feeding areas.

2 NMFS, 

UAF

0 50 50 0 0 2 years 100 Perhaps involving 

aquaria studies.

40. Assess the biological 

benefits, costs, and 

implementation feasibility

of potential protection or 

restoration measures for 

particular habitats

important to CI beluga 

recovery and implement 

such measures if 

determined warranted.

2 NMFS, 

UAF

0 0 40 40 40 3 years 120 Costs for this action 

item address only the 

analyses of the 

biological benefits, 

costs, and feasibility of 

potential protection 

and restoration 

measures and not the 

implementation of 

such measures.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-15

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

41. Work with local, state, and 

federal agencies and 

stakeholders to develop a 

comprehensive Cook Inlet 

habitat database, and 

methods and plans for 

reducing or mitigating the 

levels of habitat loss or 

degradation in areas of 

known importance to CI 

belugas for foraging and 

reproduction, including 

restoration of habitats if 

necessary.

2 NMFS, 

ADFG, 

NGOs

0 0 0 0 0 5 years 0 Implemented as part of 

ongoing management 

processes; assumes no 

additional costs apart 

from those identified 

in Action 34. Could be 

organized and 

supported by the 

NMFS Cook Inlet 

Beluga Recovery 

Coordinator (Action 

2).

42. Identify potential likely 

sources of contamination

and evaluate their 

potential to discharge 

contaminants.

2 NMFS, 

EPA, CIK

0 0 50 0 0 once every 5 

years

500 Costs associated with 

developing a 

comprehensive 

inventory or database.

UNAUTHORIZED TAKE

43. Review available data 

which may provide 

information about the 

types and level of 

unauthorized take in living 

and dead CI belugas to 

improve knowledge about

the prevalence, frequency, 

and severity of effects on 

CI belugas from these 

activities.

2 NMFS, 

ASLC, 

AVPS, 

LGL

70 0 0 0 once every 5 

years

700
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-16

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

44. Review and continue to 

monitor for signs of 

trauma in living and 

deceased CI belugas to 

assess the 

presence/absence of 

indications of trauma from 

entanglements or vessel 

strikes in living whales, 

and the percentage of 

necropsied CI belugas 

with mortalities attributed 

to or associated with 

anthropogenic trauma.

2 NMFS, 

ASLC, 

AVPS, 

LGL

50 0 0 0 0 once every 5 

years

500 AVPS and ASLC 

conduct majority of CI 

beluga necropsies and 

document signs of 

trauma in dead whales; 

LGL documents signs 

of trauma in living 

whales. Costs are 

associated with 

reviewing the 

information to 

determine levels of 

injury/mortality from 

anthropogenic causes.

45. Refine research 

techniques, evaluate 

alternatives, and 

implement research 

methods which minimize 

harassment, harm, and 

general adverse impacts 

on CI belugas. Only 

conduct research on CI 

belugas that has a clear 

connection to their 

recovery.

2 NMFS 0 0 0 0 0 yearly 0 These evaluations and 

decisions can be 

associated with the 

annual meetings 

recommended in 

Action 7.

46. Evaluate the relative effect 

of different types of 

vessels and speed on CI 

belugas.

2 NMFS, 

ADFG

0 0 60 0 0 once 60
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-17

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

47. Work with local, state, and 

federal agencies and 

stakeholders to: 1) 

monitor vessel activity in 

areas of known 

importance to CI belugas 

for foraging and 

reproduction; 2) develop a 

cooperative program to 

reduce whale interactions 

with vessels and fisheries;

and 3) develop methods 

and plans for reducing or 

mitigating the levels of 

entanglements, vessel 

strikes, or other sources of 

anthropogenic trauma for 

areas of critical 

importance to CI belugas 

for reproduction and

foraging.

2 NMFS, 

ADFG

0 20 20 30 30 yearly for 5 

years, then 

once every 5 

years

550 Discussions should 

start in Year 1 (at no 

additional costs); 

monitoring vessel 

activity starts in Year 

2; and assessing the 

need for boating 

guidelines and plans 

for mitigation begin in 

Year 4. Initial 5 years 

estimated at $100K, 

with a 5-year review 

cost of $50K.

CATASTROPHIC EVENTS

48. Using currently available 

information, conduct a 

retrospective spatial and 

temporal evaluation of 

known catastrophic events 

in Cook Inlet since the 

1970s, and assess if there 

are changes in the

frequency, distribution, or 

types of catastrophic 

events over time.

2 NMFS, 

ADEC

100 0 0 0 0 once every 5 

years

1000
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-18

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

49. Review catastrophic 

events in areas known to 

be important to CI belugas 

for foraging or 

reproduction and assess if 

a correlation exists with 

CI beluga distribution, 

abundance, or reported 

mortalities that may 

suggest catastrophic 

events are limiting 

recovery.

2 NMFS, 

ADEC

50 0 0 0 0 once every 5 

years

500 May be informed by 

results of Action 48.

50. Conduct a retrospective 

analysis of documented CI 

beluga live strandings and 

catastrophic events in 

Cook Inlet and assess if a 

correlation exists which 

may indicate catastrophic 

events are limiting 

recovery by causing mass 

strandings.

2 NMFS, 

ASLC

50 0 0 0 0 once every 5 

years

500 May be informed by 

results of Action 48.

51. Review available data 

which may provide 

information about 

mortality rates (e.g., CI 

beluga stranding records) 

and assess if the

occurrence of mortality is 

correlated with known 

catastrophic events.

2 NMFS, 

ASLC

50 0 0 0 0 once every 5 

years

500 May be informed by 

results of Action 48.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-19

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

52. Assess CI belugas for 

signs of catastropheinduced distress to 

determine whether 

mortalities or reduced 

fitness can be directly or 

indirectly attributed to 

catastrophes.

2 NMFS, 

LGL, 

ASLC

30 0 0 0 0 review is 

once every 5 

years; 

monitoring 

is ongoing

300 Funds for monitoring 

are assumed to be 

included in other 

actions that fund 

population monitoring 

(e.g., Action 1).

53. Review and update oil 

spill response plans to 

minimize effects of spills

on CI belugas, including 

strategies to deter CI 

belugas from entering 

oiled areas. 

2 NMFS, 

USCG, 

ADEC, 

EPA, 

CISPRI

0 25 0 0 0 once every 5 

years

250

54. Evaluate and test deterrent 

or hazing strategies aimed 

at preventing belugas from 

entering specific areas of 

concern.

2 NMFS, 

USCG, 

ADEC, 

EPA, 

CISPRI

0 20 20 25 0 3 years then 

once every 5 

years (at 

$25K)

290

55. Hold annual drills to 

respond to belugas 

impacted by catastrophic 

events.

2 NMFS, 

USCG, 

EPA, 

ADEC, 

CISPRI

0 20 20 20 20 yearly 980 Could be coordinated 

with the annual Alaska 

Marine Mammal 

Stranding Network 

meeting.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-20

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

CUMULATIVE EFFECTS OF MULTIPLE STRESSORS

56. Conduct a temporal and 

spatial analysis of all types 

and sources of threats to 

CI belugas, documenting 

times and areas where 

threats overlap, and assess 

if a correlation exists with 

CI beluga abundance or 

distribution which may 

suggest the effects of 

multiple stressors are 

limiting CI beluga 

recovery.

2 NMFS 150 0 0 0 0 once every 5 

years

1500

57. Conduct a meta-analysis 

of previously documented 

cumulative effects for 

other populations and 

species, based on known 

threats for CI belugas, and 

prioritize risk to CI 

belugas based on how 

these threats have been 

shown to negatively affect 

other beluga populations, 

other odontocetes, or other 

marine mammals.

2 NMFS 100 0 0 0 0 once every 5 

years

1000

58. Analyze the potential 

synergism among noise 

exposure, chemical 

pollutants, and potential 

predation to identify if 

there are activities, 

locations, or periods of 

time for which CI belugas 

may be at high risk for 

synergistic effects.

2 NMFS 100 0 0 0 0 once every 5 

years

1000
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-21

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

59. Review the CI beluga 

stranding records for cooccurrence of multiple 

stressors.

2 NMFS, 

ASLC

0 10 5 5 5 yearly 250

60. Evaluate sequential effects 

compared to effects of 

multiple co-occurring 

stressors.

2 NMFS 0 10 10 10 10 yearly for 5 

years, then 

once every 5 

years

140

61. Develop a PVA model 

component to incorporate 

covariance effects of 

multiple stressors.

2 NMFS 0 0 0 50 0 once 50 Similar to other PVA 

model parameters, 

once developed, this 

parameter will be 

incorporated into the 

model.

62. Review the current system 

for allocation of takes (by 

harassment) of CI belugas 

to see if a comprehensive 

approach, rather than by 

individual project, 

increases managers’ 

ability to reduce the 

cumulative effects of 

harassment takes by 

numerous projects.

2 NMFS 0 0 300 0 0 once 300

63. Encourage the resources 

users/development 

community in Cook Inlet 

to create a joint industry 

program to gather and 

compile data to share for 

consultation, permitting, 

and mitigation processes, 

and to fund research to 

improve mitigation of 

impacts on CI belugas and 

their habitat. 

2 MMC, 

AOGA, 

NGOs, 

Cook Inlet 

resource 

users

0 30 25 20 20 yearly 995 Assumes higher costs 

initially to start 

program, then $20K 

annually.
Cook Inlet Beluga Whale VII. IMPLEMENTATION SCHEDULE

Recovery Plan

VII-22

Action # Action description Priority

Potential 

resp. 

partiesa

FY1

$K

FY2

$K

FY3

$K

FY4

$K

FY5

$K

Duration or 

frequency 

of action

50-year 

cost 

($K) Comments

64. Consider analysis of 

results for cumulative 

effects of multiple 

stressors to update 

regulations.

2 NMFS, 

MMC

0 0 0 0 85 once 85

a Potential Responsible Parties: ADEC = Alaska Department of Environmental Conservation; ADFG = Alaska Department of Fish and Game; ADNR = Alaska Department of 

Natural Resources; AOGA = Alaska Oil and Gas Association; ASLC = Alaska SeaLife Center; AVPS = Alaska Veterinary Pathology Services; CIBA = Cook Inlet Beluga 

Acoustics group; CIK = Cook Inletkeeper; CIRCAC = Cook Inlet Regional Citizens Advisory Committee; CISPRI = Cook Inlet Spill Prevention Response, Inc.; DOW = 

Defenders of Wildlife; EPA = Environmental Protection Agency; LGL = LGL Alaska Research Associates, Inc.; MMC = Marine Mammal Commission; NGOs = Nongovernmental Organizations; NMFS = National Marine Fisheries Service; UA = University of Alaska; USCG = United States Coast Guard.
Cook Inlet Beluga Whale VIII. LITERATURE CITED

Recovery Plan

VIII-1

VIII. LITERATURE CITED

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ADF&G. 2004. Fish Distribution Database – Interactive Mapping. Available at:

http://www.adfg.alaska.gov/sf/SARR/AWC/index.cfm?ADFG=main.interactive.

ADF&G. 2006. Our wealth: a strategy for conserving Alaska’s diverse wildlife and fish 

resources. ADF&G, Juneau. Xviii + 824 p.

ADF&G Salmon Research Team. 2013. Chinook salmon stock assessment and research plan. 

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adapt. Alaska Sea Grant, University of Alaska Fairbanks, Publication M-158, 2 p.

Allen, B.M., and R.P. Angliss. 2012. Alaska marine mammal stock assessments, 2011. U.S. 

Department of Commerce, NOAA Technical Memorandum NMFS-AFSC-234. 288 p.

Anderson, P.J., and J.F. Piatt. 1999. Community reorganization in the Gulf of Alaska following 

ocean climate regime shift. Marine Ecology Progress Series 189:117–223.

Angiel, N.M. 1997. The vocal repertoire of the beluga whale in Bristol Bay, Alaska. M.S. thesis, 

University of Washington, Seattle, WA.

Angliss, R.P., D.P. DeMaster, and A.L. Lopez. 2001. Alaska marine mammal stock assessments, 

2001. U.S. Department of Commerce, NOAA Technical Memorandum NMFS-AFSC124. 203 p.

Angliss, R.P., and K.L. Lodge. 2002. Alaska marine mammal stock assessments, 2002. U.S. 

Department of Commerce, NOAA Technical Memorandum NMFS-AFSC-133. 224 p.

Angliss, R.P., G.K. Silber, and R. Merrick. 2002. Report of a workshop on developing recovery 

criteria for large whale species. U.S. Department of Commerce, NOAA Technical

Memorandum NMFS-F/OPR-21, 23 p. + appendices.

Armstrong, T. 1985. White whales trapped in sea ice. Polar Record 22:552.

Au, W.W.L. 1993. The sonar of dolphins. Springer, New York, p. 277.

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beluga whale echolocation signals. Journal of the Acoustical Society of America 

77(2):726–730.
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VIII-2

Au, W.W.L., R.H. Penner, and C.W. Turl. 1987. Propagation of beluga echolocation signals. 

Journal of the Acoustical Society of America 82(3):807–813.

Awbrey, F.T., J.A. Thomas, and R.A. Kastelein. 1988. Low frequency underwater hearing 

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America 84(6):2273–2275.

Bailey, K.M. 2000. Shifting control of recruitment of walleye pollock Theragra chalcogramma

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Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan

IX-1

IX.APPENDICES

A. Federal Actions and Regulations for CI Belugas

B. Existing Conservation Efforts

C. Recovery Planning for CI Belugas

D. CI Beluga Life History Supplement

E. CI Beluga Hearing, Vocalizations, and Noise Supplement

F. CI Beluga Prey Supplement

G. CI Beluga Pollution and Contaminants Supplement

H. Cause of Death Analysis

I. Common and Scientific Names
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan

IX-2

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Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan A – Federal Actions and Regulations for CI Belugas

IX-3

A. Federal Actions and Regulations for CI Belugas

Date Action Regulation

August 31, 1988 CI belugas included in the List of Candidate Vertebrate and Invertebrate 

Marine Species for possible listing under ESA

53 FR 33516

November 19, 1998 NMFS initiated a status review of CI belugas to determine whether 

designation as depleted under MMPA or listing as threatened or 

endangered under ESA is warranted

63 FR 64228

January 21, 1999 NMFS received petition to designate CI belugas as depleted under 

MMPA 

Not applicable

March 3, 1999 NMFS received petitions to list CI belugas as endangered under ESA N/A

April 9, 1999 NMFS determined petitions presented substantial information indicating 

the petitioned actions may be warranted 

64 FR 17347

May 21, 1999 MMPA amended to require cooperative agreements to harvest CI 

belugas between NMFS and affected Alaska Native organizations

Pub. L. No. 106–31, 

Section 3022, 113 Stat. 

57, 100

October 19, 1999 NMFS proposed designating the CI beluga stock as depleted under 

MMPA

64 FR 56298

May 31, 2000 CI beluga stock listed as depleted under MMPA 65 FR 34590

June 22, 2000 NMFS determined ESA listing not warranted; established CI beluga

stock as a DPS and thus as a “species” as defined under ESA

65 FR 38778

October 4, 2000 NMFS proposed regulations to regulate subsistence harvest of CI 

belugas by Alaska Natives

65 FR 59164

December 21, 2000 MMPA amendment (May 21, 1999) on subsistence harvest of CI 

belugas by Alaska Natives made permanent

Pub. L. No. 106–553, 

114 Stat. 2762, 2762A–

108

September 26, 2003 Notice of Availability published for the Subsistence Harvest 

Management of CI Beluga Whales Final Environmental Impact 

Statement (EIS)

68 FR 55604

April 6, 2004 NMFS released final interim regulations to govern subsistence harvest 

of CI belugas by Alaska Natives

69 FR 17973

April 15, 2004 CI belugas transferred from ESA Candidate Species List to newly 

created Species of Concern List

69 FR 19975

March 16, 2005 NMFS published a Notice of Availability of the MMPA Draft 

Conservation Plan for the CI Beluga Whale

70 FR 12853

March 24, 2006 NMFS initiated a status review to determine if CI belugas should be 

listed under ESA 

71 FR 14836

March 29, 2006 NMFS published a Notice of Intent to prepare a supplemental EIS 

(SEIS) for long-term management of CI beluga subsistence harvest by 

Alaska Natives

71 FR 15697

April 2006 NMFS received a petition to list CI belugas as endangered under ESA Not applicable

August 7, 2006 NMFS determined petition presented substantial information indicating 

that the petitioned action may be warranted

71 FR 44641

April 20, 2007 NMFS published proposed rule to list CI belugas as endangered under 

ESA

72 FR 19854
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan A – Federal Actions and Regulations for CI Belugas

IX-4

Date Action Regulation

December 28, 2007 Notice of Availability published for the CI Beluga Whale Subsistence 

Harvest Draft SEIS

72 FR 73798

April 22, 2008 NMFS extended the deadline for ESA listing decision six months 73 FR 21578 

June 20, 2008 Notice of Availability published for the CI Beluga Whale Subsistence 

Harvest Final SEIS

73 FR 60976

October 15, 2008 NMFS published final regulations establishing long-term management 

of subsistence harvest of CI belugas by Alaska Natives

73 FR 60976

October 22, 2008 NMFS issued final rule to list the DPS of the beluga whale found in 

Cook Inlet, Alaska, as endangered under ESA

73 FR 62919

October 22, 2008 NMFS published a Notice of Availability of the final MMPA 

Conservation Plan for the Cook Inlet Beluga Whale

73 FR 62961

December 2, 2009 NMFS proposed to designate critical habitat for CI belugas under ESA 74 FR 63080

January 28, 2010 NMFS published a Notice of Intent to prepare a recovery plan for CI 

belugas

75 FR 4528

April 11, 2011 NMFS issued the final rule designating critical habitat for CI belugas

under ESA

76 FR 20180

May 15, 2015 NMFS published a Notice of Availability of the Draft Recovery Plan for 

the Cook Inlet Beluga Whale and opened a 60-day public comment 

period

80 FR 27925
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan B – Existing Protective Measures

IX-5

B. Existing Conservation Efforts

NOTE TO READER: The text below was included in the draft recovery plan developed by the 

CIBRT, with minor updates, as a detailed description of existing conservation efforts that cover 

CI belugas, although we note that existing measures have been inadequate to date to effectively 

ensure the recovery of CI belugas. We also note that this Appendix is not intended to provide an 

exhaustive review of every existing protective measure that may apply to threats that may be 

limiting CI beluga recovery. Other such protections not detailed here include federal statutes 

such as the Oil Pollution Act of 1990, Magnuson-Stevens Fishery Conservation and 

Management Act, and Outer Continental Shelf Lands Act; and state statutes such as the 

Anadromous Fish Act and Oil and Hazardous Substance Pollution Control Act. All of the

information in this Appendix is reproduced from publicly available laws, reports, or other 

sources of information. In an effort to improve readability of the recovery plan and to give the 

reader the basic information necessary to understand the recovery criteria and actions, we 

removed the following text from the body of the document. However, we have preserved this text 

to present to readers interested in the details of the discussion.

1. Federal Protections

The Department of Commerce, through the National Oceanographic and Atmospheric 

Administration’s (NOAA) NMFS, is charged with protecting whales, dolphins, porpoises, seals, 

and sea lions. Management responsibility for belugas in Alaska has been delegated by the 

Secretary of Commerce to NMFS, and NMFS Alaska Region (AKR) assumes primary 

responsibility for CI beluga recovery. 

Walrus, manatees, otters, and polar bears are protected by the Department of the Interior 

through the U.S. Fish and Wildlife Service (USFWS). The Animal and Plant Health Inspection 

Service, a part of the Department of Agriculture, is responsible for regulations managing marine 

mammals in captivity.

a. The Marine Mammal Protection Act

All marine mammals in U.S. waters, including CI belugas, are federally protected under the 

MMPA of 1972, as amended. The MMPA established a national policy to prevent marine 

mammal species and population stocks in U.S. waters from declining to the point where they 

cease to be significant functioning elements of the ecosystems of which they are a part. The 

MMPA presents a single comprehensive federal program to take the place of formerly state-run 

programs, and includes protection for population stocks in addition to species and subspecies. 

Nowhere else in the world had a government made the conservation of healthy and stable 

ecosystems as important as the conservation of individual species

The MMPA was enacted in response to increasing concerns that some marine mammal 

species or stocks may be in danger of extinction or depletion as a result of human activities and 

that measures should be taken to replenish these species or stocks so that they did not fall below 

their optimum sustainable population (OSP) level, thus resulting in a “depleted” population. The 

MMPA established the concept of OSP to ensure healthy ecosystems. 

The MMPA prohibits, with certain exceptions, the “take” of marine mammals in U.S. waters 

and by U.S. citizens on the high seas, and prohibits the importation of marine mammals and 

marine mammal products into the U.S. 
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The MMPA has been amended several times since 1972, but the most substantial 

amendments were in 1994 and provided:

• Certain exceptions to the take prohibitions, including: small takes incidental to specified 

activities; when access by Alaska Natives to marine mammal subsistence resources can 

be preserved; and permits and authorizations for scientific research; 

• A program to authorize and control the taking of marine mammals incidental to 

commercial fishing operations; 

• Preparation of stock assessments for all marine mammal stocks in waters under U.S. 

jurisdiction; and 

• Studies of pinniped-fishery interactions. 

The MMPA is organized into five “titles.” Title I, Conservation and Protection of Marine 

Mammals, is the most comprehensive. Title I established a moratorium on the taking of marine 

mammals in U.S. waters. “Take” is defined by section 3(13) of the MMPA (16 U.S.C. § 

1362(13)) as “to harass, hunt, capture, or kill or attempt to harass, hunt, capture, or kill any 

marine mammal.” Under the 1994 amendments to the MMPA, harassment is further defined as 

any act of pursuit, torment, or annoyance which:

• (Level A Harassment) has the potential to injure a marine mammal or marine mammal 

stock in the wild; or,

• (Level B Harassment) has the potential to disturb a marine mammal or marine mammal 

stock in the wild by causing disruption of behavioral patterns, including, but not limited 

to, migration, breathing, nursing, breeding, feeding, or sheltering but which does not have 

the potential to injure a marine mammal or marine mammal stock in the wild.

The moratorium generally does not apply to Alaska Natives who live on the Alaskan coast. 

Section 101(b) of the MMPA (16 U.S.C. § 1371(b)) contains provisions allowing for take by 

Alaska Natives for subsistence use or to create and sell “authentic native articles of handicrafts 

and clothing” without permits or authorizations. However, the taking must not be “accomplished 

in a wasteful manner,” and the Secretaries of Commerce and the Interior may regulate the taking 

of a depleted species or stock, regardless of the purpose for which it is taken. Exceptions to the 

moratorium can be made through permitting actions for take incidental to commercial fishing 

and other nonfishing activities (section 118), for scientific research (section 104), and for public 

display at licensed institutions such as aquaria and science centers (section 104). The MMPA 

shifts the burden from resource managers to resource users to show that proposed taking of 

living marine resources will not adversely affect the resource or the ecosystem. 

Section 115 of Title I requires that the Secretary of Commerce make a determination if a 

species or stock should be designated as depleted, or should no longer be designated as depleted, 

on the basis of the best scientific information available. For any species or stock designated as 

depleted under the MMPA and for which NMFS has management responsibility, section 115 

also requires the Secretary of Commerce to prepare a Conservation Plan. Conservation Plans 

should be prepared as soon as possible for any species or stock designated as depleted. Each plan 

shall have the purpose of conserving and restoring the species or stock to its OSP. The MMPA 

requires that Conservation Plans to be modeled after recovery plans required under section 4(f) 

of the ESA of 1973. In May 2000, NMFS designated the CI beluga stock as depleted under the 
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MMPA. In October 2008, NMFS published the Conservation Plan for the Cook Inlet Beluga 

Whale and identified 780 belugas as the OSP required to reconsider the depleted designation.

Section 119 of Title I (Marine Mammal Cooperative Agreements in Alaska) states that the 

Secretary may enter into cooperative agreements with Alaska Native organizations to conserve 

marine mammals and provide co-management of subsistence use by Alaska Natives. The MMPA 

also authorizes NMFS to implement subsistence harvest limits through regulation of depleted 

marine mammal stocks, following an administrative hearing on the record. In October 2000, 

NMFS proposed regulations to limit the beluga subsistence harvest in Cook Inlet, Alaska. An 

administrative hearing was held in December 2000, and interim subsistence harvest regulations 

for 2001 to 2004 were developed. In August 2004, a second administrative hearing was held to 

determine the long-term subsistence harvest regime. NMFS signed a co-management agreement 

with the CIMMC in 2005 and 2006, allowing two belugas to be successfully harvested in those 

years. In June 2008, NMFS published the Cook Inlet Beluga Whale Subsistence Harvest Final 

Supplemental Environmental Impact Statement (EIS); in September 2008, the record of decision 

associated with this EIS was signed. Final regulations governing long-term management of the 

subsistence harvest of CI belugas by Alaska Natives were published in October 2008.

Title II established the Marine Mammal Commission (MMC), an agency of the U.S. 

Government responsible for providing independent oversight of the marine mammal 

conservation policies and programs being carried out by federal regulatory agencies. The MMC 

is charged with the following duties:

• Undertake a review and study of the activities of the United States pursuant to existing 

laws and international conventions relating to marine mammals, including, but not 

limited to, the International Convention for the Regulation of Whaling, the Whaling 

Convention Act of 1949, the Interim Convention on the Conservation of North Pacific 

Fur Seals, and the Fur Seal Act of 1966. 

• Conduct a continuing review of the condition of the stocks of marine mammals, of 

methods for their protection and conservation, of humane means of taking marine 

mammals, of research programs conducted or proposed to be conducted under the 

authority of the MMPA, and of all applications for permits for scientific research, public 

display, or enhancing the survival or recovery of a species or stock.

• Undertake or cause to be undertaken such other studies as it deems necessary or desirable 

in connection with its assigned duties as to the protection and conservation of marine 

mammals.

• Recommend to the Secretary of Commerce and to other federal officials such steps as it 

deems necessary or desirable for the protection and conservation of marine mammals.

• Recommend to the Secretary of State appropriate policies regarding existing international 

arrangements for the protection and conservation of marine mammals and suggest 

appropriate international arrangements for the protection and conservation of marine 

mammals.

• Recommend to the Secretary of Commerce such revisions of the endangered species list 

and threatened species list published pursuant to section 4(c)(1) of the ESA of 1973 as 

may be appropriate with regard to marine mammals.
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• Recommend to the Secretary of Commerce, other appropriate federal officials, and 

Congress such additional measures as it deems necessary or desirable to further the 

policies of the MMPA, including provisions for the protection of the Indians, Eskimos, 

and Aleuts whose livelihood may be adversely affected by actions taken pursuant to the 

MMPA.

The MMC is primarily an oversight and advisory body. Although federal agencies are not 

required to adopt the MMC’s recommendations, the MMPA specifies that an agency that 

declines to follow any such recommendations is required to provide detailed written explanations 

to the MMC within 120 days.

Title III of the MMPA focuses on the International Dolphin Conservation Program. Title IV 

is the origination of the Marine Mammal Health and Stranding Response program, and includes 

information about stranding response agreements, the National Marine Mammal Tissue Bank, 

and the John H. Prescott Marine Mammal Rescue Assistance Grant Program. Title V is dedicated 

to polar bears.

b. The Endangered Species Act of 1973

Congress passed the ESA on December 28, 1973, recognizing that the natural heritage of the 

United States was of “esthetic, ecological, educational, recreational, and scientific value to our 

Nation and its people” (ESA section 2(a)(3)). It was understood that, without protection, many of 

our nation’s living resources would become extinct. The ESA provides for the conservation of 

species that are endangered or threatened throughout all or a significant portion of their range, 

and the conservation of the ecosystems on which they depend. The USFWS and NMFS share 

responsibility for implementing the ESA. There are more than 1,900 species listed under the 

ESA. NMFS is responsible for 74 marine species, including CI belugas. 

A species is considered endangered if it is in danger of extinction throughout all or a 

significant portion of its range. A species is considered threatened if it is likely to become 

endangered in the foreseeable future. The listing of a species as endangered makes it illegal to 

“take” (harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, collect, or attempt to do 

these things) that species (ESA section 9(a)(1)). Similar prohibitions are usually extended to 

threatened species. Federal agencies may be allowed limited take of species through interagency 

consultations with NMFS or USFWS. Non-federal individuals, agencies, or organizations may 

have limited take through special permits under conservation plans. Effects to the listed species 

must be minimized, and in some cases conservation efforts are required to offset the take. The 

NMFS Office of Law Enforcement works with the U.S. Coast Guard and other partners to 

enforce and prosecute ESA violations. 

NMFS conserves and recovers marine resources by implementing the different programs 

provided for by the ESA. The ESA is divided into 18 sections; only a few will be highlighted 

here, with emphasis placed on sections 4, 6, and 7.

Under the authority provided by section 4 of the ESA (Determination of Endangered Species 

and Threatened Species), NMFS lists species as endangered or threatened, designates critical 

habitat, and develops and implements recovery plans for listed species. NMFS conducts periodic 

reviews of species to ensure that they are listed appropriately. Because the ESA requires such 

reviews to be conducted at least once every five years, these reviews are referred to as five-year 

reviews. Section 4(f) of the ESA directs NMFS to develop and implement recovery plans for 
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threatened and endangered species, unless such a plan would not promote conservation of the 

species. According to the statute, these plans must incorporate, at a minimum:

• A description of site-specific management actions necessary to achieve the plan’s goal for 

the conservation and survival of the species; 

• Objective, measurable criteria which, when met, would result in a determination that the 

species may be removed from the list; and 

• Estimates of the time and cost required to carry out those measures needed to achieve the 

plan’s goal and to achieve intermediate steps toward that goal. 

The NMFS is authorized to procure the services of public and private entities to assist in the 

development and implementation of recovery plans, including the appointing of recovery teams. 

Many, but not all, recovery plans are written by recovery teams and, in some cases, 

implementation of plans is guided by recovery teams. NMFS has made a concerted effort in 

recent years to include representative stakeholders (those with an interest in the species) on 

recovery teams and to involve the public in recovery planning. All recovery plans are made 

publically available in draft form and public comments are solicited before the plan is finalized, 

ensuring that the public has an opportunity to provide input in the recovery planning process. 

Implementation of recovery actions is the responsibility of all Americans, but tends to fall 

largely on federal, state and local agencies, tribes, interested organizations, and individuals 

within the range of the species. 

Section 6 of the ESA (Cooperation with States) provides a mechanism for cooperation 

between NMFS and states in the conservation of threatened, endangered, and candidate species. 

NMFS is authorized to enter into agreements with any state that establishes and maintains an 

“adequate and active” program for the conservation of endangered and threatened species. Once 

a state enters into such an agreement, NMFS is authorized to assist in, and provide federal 

funding for, implementation of the state’s conservation program. In 2009, the State of Alaska 

and NMFS formalized a limited cooperative conservation partnership agreement for the 

conservation and protection of endangered and threatened species pursuant to section 6 of the 

ESA.

32 This agreement gives the State of Alaska eligibility to compete against other states for 

section 6 funding under the Species Recovery Grant Program, an annual national competition. 

This federal grant funding is to be used to support management, outreach, research, and 

monitoring projects that have direct conservation benefits for listed species, recently de-listed 

species, and candidate species that reside within that State. To date, no funding has been awarded 

to the State of Alaska specifically for CI belugas under this program. Section 6 of the ESA also 

allows state laws to be more restrictive than the ESA regarding taking of listed species; however, 

state laws cannot be less restrictive.

Section 7 of the ESA (Interagency Cooperation) requires federal interagency cooperation as 

another means to conserve federally listed species and designated critical habitat. Section 7(a)(1) 

requires NMFS to review other programs administered by NMFS and utilize such programs to 

 

32 A copy of the agreement can be viewed on the NMFS AKR website at: http://alaskafisheries.noaa.gov/pr/section-6-agreements.
Cook Inlet Beluga Whale IX. APPENDICES

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further the purposes of the ESA. It also directs all other federal agencies to utilize their 

authorities in furtherance of the purposes of the ESA by carrying out programs for the 

conservation of listed species. Under section 7(a)(2), federal agencies must consult with NMFS 

on activities that may affect a listed species or its designated critical habitat. These interagency, 

or section 7, consultations are designed to assist federal agencies in fulfilling their duty to ensure 

any action they authorize, fund, or carry out is not likely to jeopardize the continued existence of 

a listed species or result in the destruction or adverse modification of designated critical habitat. 

In fulfilling these requirements, each agency must use the best scientific and commercial data 

available.

Section 8 (International Cooperation) allows NMFS to partner with other nations to ensure 

that international trade does not threaten species. Section 9 (Prohibited Acts) addresses 

enforcement of the ESA and investigations of violations. Section 10 (Exceptions) allows NMFS 

to cooperate with non-federal partners to develop conservation plans for the long-term 

conservation of species, as well as permitting research to learn more about protected species. 

States, local agencies, and private entities may conduct conservation actions as a means to 

minimize or mitigate incidental take of a species as part of a Conservation Plan under section 10 

of the ESA. Any entity or individual may also take proactive measures to promote recovery of 

listed species, although some of these activities may require a section 7 consultation or section 

10 permit.

c. The Fish and Wildlife Coordination Act

The Fish and Wildlife Coordination Act (FWCA) of 1934 (16 U.S.C. 661 et seq.), as 

amended, requires that fish and wildlife resources receive equal consideration to other project 

features and that all federal agencies consult with NMFS, USFWS, and state wildlife agencies 

when proposed actions might result in modification of a natural stream or body of water. Thus, 

FWCA provides the basic authority for NMFS and USFWS involvement in evaluating impacts to 

fish and wildlife from proposed water resource development projects.

Specifically, consultation is required in instances where the “waters of any stream or other 

body of water are proposed or authorized, permitted or licensed to be impounded, diverted, or 

otherwise controlled or modified” by any agency under a federal permit or license. The purpose 

of the consultation is to prevent “loss of and damage to wildlife resources” by determining the 

possible harm to fish and wildlife resources, and the measures that are needed to both prevent the 

damage to and loss of these resources, and to develop and improve the resources, in connection 

with water resource development. 

FWCA allows NMFS to submit comments and recommendations to federal licensing and 

permitting agencies and to federal agencies conducting construction projects on the potential 

harm to living marine resources caused by the proposed water development project, and submit 

recommendations to prevent harm. NMFS routinely provides comments to the Corps during 

review of projects under section 404 of the Clean Water Act (CWA) (governing the discharge of 

dredged materials into navigable waters) and section 10 of the Rivers and Harbors Act of 1899 

(governing obstructions in navigable waterways). 

d. The Coastal Zone Management Act of 1972

The U.S. Congress recognized the importance of meeting the challenge of continued growth 

in the coastal zone by passing the Coastal Zone Management Act (CZMA) (16 U.S.C. 1451 et 
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seq.) in 1972. The Act, administered by NOAA’s Office of Ocean and Coastal Resource 

Management, provides for management of the nation’s coastal resources, including the Great 

Lakes, and balances economic development with environmental conservation. 

The CZMA outlines two national programs, the National Coastal Zone Management Program 

and the National Estuarine Research Reserve System. The coastal programs aim to balance 

competing land and water issues in the coastal zone, while estuarine reserves serve as field 

laboratories to provide a greater understanding of estuaries and how humans impact them. 

Through the CZMA, Congress declared it is national policy “to preserve, protect, develop, and 

where possible, to restore or enhance, the resources of the Nation's coastal zone for this and 

succeeding generations.” 

The National Coastal Zone Management Program is a voluntary partnership between the 

federal government and U.S. coastal and Great Lake states and territories authorized by the 

CZMA to address national coastal issues. The CZMA provides the basis for protecting, restoring, 

and responsibly developing our nation’s diverse coastal communities and resources. To meet the 

goals of the CZMA, the National Coastal Zone Management Program takes a comprehensive 

approach to coastal resource management—balancing the often competing and occasionally 

conflicting demands of coastal resource use, economic development, and conservation. Some of 

the key elements of the National Coastal Zone Management Program include:

• Protecting natural resources; 

• Managing development in high hazard areas; 

• Giving development priority to coastal-dependent uses; 

• Providing public access for recreation; and 

• Coordinating state and federal actions. 

In 2015, 34 states and territories had approved coastal management programs that address a 

wide range of issues, including coastal development, water quality, public access, habitat 

protection, energy facility siting, ocean governance and planning, coastal hazards, and climate 

change. By using both federal and state funds, the program strengthens the capabilities of each 

partner to address coastal issues. While the Act includes basic requirements for state partners, it 

also gives them the flexibility to design programs that best address their unique coastal 

challenges and laws and regulations. 

The Alaska Coastal Management Program (ACMP) was discontinued July 1, 2011. This 

program was previously under the Alaska Department of Natural Resource’s Division of Coastal 

and Ocean Management, and set forth statewide standards governing natural resource 

development and conservation in Alaska’s coastal zones, including specific standards for habitats 

and subsistence. Section 307 of the CZMA requires the state to review most federal activities and 

federally-permitted activities affecting resources within the state’s coastal zone and to ensure that 

state-permitted activities are consistent with standards and policies of the ACMP. However, on 

May 14, 2011, the Alaska State Legislature adjourned a special legislative session without 

passing legislation necessary to extend the ACMP (AS 44.66.030). Alaska is the only coastal 

state in the United States without a Coastal Management Program.
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e. The Clean Water Act 

The primary objective of the Federal Water Pollution Control Act of 1948, more commonly 

known as the Clean Water Act (CWA), is to restore and maintain the chemical, physical, and 

biological integrity of the nation’s surface waters. The EPA is the federal agency responsible for 

creating and enforcing national water quality regulations under the CWA. The CWA regulates

the discharges of pollutants into the waters of the U.S., and in doing so, is aimed at ensuring that 

the Nation’s waters are fishable, swimmable, and drinkable.

The EPA, the Corps, and the State of Alaska all have a role in the implementation and 

enforcement of the CWA in Alaska. Section 303(d) of the CWA requires states to prepare a list 

of all impaired waters within their jurisdiction. The State of Alaska’s Department of 

Environmental Conservation (ADEC) assesses the quality of Alaska’s water bodies by utilizing a 

multi-agency task force, and reviews information provided on water bodies through a nomination 

and public solicitation process. Each nominated water body is then analyzed to determine if the 

existing protections are sufficient to meet water quality, water quantity, and habitat needs. These 

reviews occur every two years, and, after a public review, the assessments are presented to the 

EPA for approval. 

Section 401 of the CWA requires that any applicant for a federal permit that may result in 

effluent being discharged into navigable waters must first be granted certification by the state 

that the proposed action will not violate state water quality standards. Such certification will 

define effluent limitations and monitoring requirements necessary for ensuring that: 1) the water 

quality sections of the CWA are upheld, and 2) applicable state laws are complied with. These 

requirements are to be incorporated as requirements in the federal permit. The purpose of this 

section is to allow the states, who define water quality standards, the opportunity to ensure that 

the Federal permits issued are protective of the designated use(s) of the receiving waters. Thus, 

this section gives significant authority to the states to have a say in compliance with water 

quality issues for waters within their jurisdiction.

Section 402 of the CWA requires that all discharges to surface waters be permitted under the 

National Pollutant Discharge Elimination System (NPDES) permit program. All dischargers 

from point sources are required to obtain a permit from the EPA under the NPDES program, 

which outlines effluent limitations based on two levels of control: technology-based criteria and 

water quality-based criteria. The more stringent of the two criteria apply. Discharging without an 

NPDES permit is unlawful. The CWA allows for states to implement (to have “primacy” for) the 

NPDES program with the EPA acting in an oversight role. 

The State of Alaska’s application for a state-run section 402 program was approved by the 

EPA on October 31, 2008. The State of Alaska’s program is referred to as the Alaska Pollutant 

Discharge Elimination System Program (APDES). The transfer of authority for permitting, 

compliance, and enforcement of the section 402 program to the ADEC includes an 

implementation plan that transfers the administration of specific program components from EPA 

to the ADEC in phases over a multi-year period. Phases I–III have successfully transferred from 

EPA to ADEC. Transfer of the final phase, Phase IV, was scheduled for October 31, 2011. In 

March 2011, ADEC proposed a one year extension of the transfer of Phase IV. ADEC assumed 

full authority to administer the wastewater and discharge permitting and compliance program for 

Alaska on October 31, 2012.
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Section 404 prohibits the discharge of dredged or fill material into the waters of the U.S., 

including wetlands, without specific authorization from the Federal Government. Section 404 of 

the CWA describes how such discharge is to be regulated and authorized. A primary goal of this 

section is the preservation of the nation’s wetlands. The EPA is responsible for general oversight 

of the program, while the Corps issues the permits authorizing discharge of dredged or fill 

materials into navigable waters of the United States, including wetlands. The EPA may authorize 

states to issue 404 permits (but the EPA/Corps still retain section 404 authority in the State of 

Alaska). All authorized discharges must avoid and minimize, to the extent practicable, adverse 

impacts to wetlands, streams, and other aquatic resources. If impacts are unavoidable, then the 

Corps may require the permittee to replace the loss of the function of that wetland or resource in 

the form of compensatory mitigation.

In Alaska, NMFS provides direct consultations to the EPA and the Corps regarding impacts 

to marine mammals, fish, and their habitats as a result of proposed activities and methods for 

avoiding such impacts.

f. Treaty Trust Responsibilities

The NMFS must also consider treaty trust responsibilities to recognize the rights and 

authorities of tribes related to the ESA and CI beluga recovery. Executive Order 13175 

(Consultation and Coordination with Indian Tribal Governments) outlines the responsibilities of 

the Federal Government in matters affecting tribal interests. In addition, Secretarial Order 

“American Indian Tribal Rights, Federal-Tribal Trust Responsibilities, and the Endangered 

Species Act” outlines NMFS’s responsibilities regarding Indian tribal rights and federal trust 

responsibilities when implementing the ESA.

2. State of Alaska Protections

In addition to the State of Alaska’s involvement under the federal laws previously discussed, 

the State also has regulatory protections in place to protect the habitat of belugas, as well as other 

fish and wildlife populations. Article 8 of the Alaska Constitution (“Natural Resources”) outlines 

the framework for management of Alaska’s renewable resources and emphasizes Alaska’s regard 

for its natural resources. 

The ADF&G is responsible for determining and maintaining a list of endangered species in 

Alaska under Alaska Statute 16.20.190. A species or subspecies of fish or wildlife is considered 

a State of Alaska endangered species when the Commissioner of ADF&G determines that its 

numbers have decreased to such an extent as to indicate that its continued existence is threatened. 

The State Endangered Species List does not currently include CI belugas, although ADF&G has 

designated the belugas in Cook Inlet as a “species of special concern.” This designation provides 

ADF&G with management responsibility and authority that includes: habitat management and 

guidelines; monitoring; information gathering and dissemination; management research on 

beluga prey species including Pacific salmon; and the recommendation and imposition of 

mitigation requirements on state-regulated activities. Because the species of special concern list 

has not been reviewed or revised since 1998, as of August 15, 2011, ADF&G instead uses the 

Alaska Comprehensive Wildlife Conservation Strategy (a.k.a. the Wildlife Action Plan)33 for 

 

33 Alaska’s Wildlife Action Plan can be viewed on the ADF&G website at: 
Cook Inlet Beluga Whale IX. APPENDICES

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management of species with conservation concerns, including CI belugas. The Wildlife Action 

Plan, finalized in August 2005 and updated since, contains conservation measures, including comanagement with Alaska Native populations and cooperation with other government agencies 

for the protection and conservation of wildlife, including CI belugas. The Plan also provides the 

basis for the development of stipulations or conditions on State-issued permits to protect belugas

and their habitat. 

More than 15 million acres of protected land surrounding Cook Inlet, including State game 

refuges, critical habitats, and special legislated management areas, support healthy populations of 

fish on which belugas prey. Each of these protected areas has a detailed management plan in 

effect that incorporates management guidelines, regulations, and permit stipulations 

implemented by Alaska’s resource conservation agencies. 

Many of the municipal governments of the communities within the Cook Inlet watershed 

have also enacted laws and regulations affecting land use, development, and other matters 

providing important local protection. 

3. International Protections

a. The Convention on International Trade in Endangered Species of Wild Fauna and 

Flora

The Convention on International Trade in Endangered Species of Wild Fauna and Flora 

(CITES) is a voluntary international agreement among governments. Its aim is to ensure that 

international trade in specimens of wild animals and plants does not threaten their survival. The 

CITES was drafted as a result of a resolution adopted in 1963 at a meeting of members of the 

International Union for the Conservation of Nature and Natural Resources (IUCN) and finalized 

in 1975. 

Countries that have agreed to be bound by CITES are known as Parties. The treaty now has 

166 Parties, including the United States. Although CITES is legally binding on the Parties, it 

does not take the place of national laws, but instead provides a framework to be respected by 

each Party, which has to adopt its own domestic legislation to ensure that CITES is implemented 

at the national level. All import, export, re-export, and introduction of species covered by the 

Convention has to be authorized through a licensing system. 

The structure of CITES is similar to the ESA, in that species are listed in appendices 

according to their conservation status. However, listed CITES species must also meet the test 

that trade is at least in part contributing to their decline. The CITES regulates international trade 

in species of animals and plants according to their conservation status, and does not protect 

species from other factors that may contribute to a species’ decline, as would the ESA.

CITES lists the species covered in three appendices according to the degree of protection 

needed. CITES Appendix I includes species threatened with extinction. Trade in specimens of 

these species is permitted only in exceptional circumstances. CITES Appendix II includes 

species not necessarily threatened with extinction, but in which trade must be controlled in order 

 

http://www.adfg.alaska.gov/index.cfm?adfg=species.wapabout.
Cook Inlet Beluga Whale IX. APPENDICES

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to avoid utilization incompatible with their survival. CITES Appendix III contains species that 

are protected in at least one country that has asked other CITES Parties for assistance in 

controlling the trade. Countries may unilaterally list species for which they have domestic 

regulation in CITES Appendix III at any time. Decisions concerning CITES Appendix I and II 

species listings and resolutions are made at meetings of the Conference of the Parties, which are 

convened approximately every two years.

For the United States, the USFWS is the lead agency for implementation of the Convention 

since the bulk of CITES-listed species are under USFWS jurisdiction. However, many species 

under the jurisdiction of NMFS are also listed, either on CITES Appendix I or II. CI belugas are 

listed in CITES Appendix II.

b. The International Union for the Conservation of Nature and Natural Resources 

The International Union for the Conservation of Nature and Natural Resources, commonly 

referred to as the IUCN or World Conservation Union, is the oldest and largest global 

environmental organization. The IUCN is composed of over 1,200 member organizations, of 

which more than 200 are government groups, including NOAA. The IUCN Red List assesses the 

extinction risk of species with the overall aim “to convey the urgency and scale of conservation 

problems to the public and policy makers, and to motivate the global community to work 

together to reduce species extinctions.”34

The IUCN classified CI belugas as “critically endangered” in 2006 having met IUCN 

criterion C2a(ii): “The population is estimated to number 207 mature individuals. There is a 71% 

probability that the growth rate of the population is negative, with the best estimate indicating 

that the population is declining by 1.2% per year. All of the mature individuals are in one 

subpopulation.”35

4. Management Measures Implemented by NMFS

The following discussion describes several of the protective management measures 

implemented by NMFS for CI belugas. See Appendix IX.A. for a summary of federal regulations 

specifically related to CI belugas.

a. Subsistence Harvest Management

The MMPA authorizes NMFS, acting on behalf of the Secretary of Commerce, to implement 

subsistence harvest limits through regulation of depleted marine mammal stocks, following an 

administrative hearing on the record. In accordance with Public Laws 106–31 (1999) and 106–

553 (2000), the annual subsistence harvest of CI belugas is allowed only under cooperative 

management agreements between NMFS and affected Alaska Native organizations. On October 

4, 2000, NMFS proposed regulations to limit the beluga harvest in Cook Inlet, Alaska. An 

administrative hearing was held in December 2000 and interim harvest regulations for 2001 to 

 

34 See IUCN’s website (http://www.iucn.org) and the Red List Classification for CI belugas: 

(http://www.iucnredlist.org/details/61442/0).

35 Guidelines and criteria for IUCN’s Red List classifications are available at: http://www.iucnredlist.org/technicaldocuments/red-list-training/red-list-guidance-docs.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan B – Existing Protective Measures

IX-16

2004 were developed and published in the Federal Register in 2004. These interim harvest 

regulations allowed for a limited harvest (1–2 belugas annually), regulated the use of beluga 

products, and established requirements for the harvests within a co-management agreement. 

With the collection of more information pertaining to CI belugas, a second administrative 

hearing was held in August 2004 to determine the long-term harvest regime (2005 and 

subsequent years, until the population recovered). Following the long-term harvest plan as 

recommended by the administrative law judge, NMFS signed a co-management agreement with 

CIMMC in 2005 and 2006 for the harvest of CI belugas, which resulted in two belugas harvested 

in 2005. NMFS published the Cook Inlet Beluga Whale Subsistence Harvest Final Supplemental 

Environmental Impact Statement in June 2008 (NMFS 2008b; 73 FR 60976), in which four 

harvest alternatives were considered. A Record of Decision and harvest regulations were 

published in October 2008, and provide a subsistence harvest plan for Alaska Natives until the 

CI beluga stock recovers. 

CIMMC was disbanded by unanimous vote by the CIMMC member Tribes’ representatives 

on June 20, 2012. CIMMC was the only Alaska Native organization to obtain a co-management 

agreement with NMFS for CI beluga subsistence harvest. Currently, NMFS has no comanagement agreements with any Alaska Native organization pertaining to CI belugas. This lack 

of a co-management agreement for CI belugas precludes the authorization of subsistence harvest 

of this stock.

b. Project Review, Environmental Analyses, and Mitigation Identification

Any action that may “take” a CI beluga requires authorization from NMFS under the MMPA 

and ESA (i.e., via an Incidental Harassment Authorization [IHA] or Letter of Authorization 

[LOA] as per the MMPA, or by an Incidental Take Statement [ITS] as per the ESA). MMPA

authorizations for take can only be granted if an activity, by itself or in combination with other 

activities, would not cause a significant adverse impact on the stock. ESA authorization for take 

can only be issued if such take does not jeopardize the continued existence of the species or 

destroy or adversely modify designated critical habitat. NMFS works with agencies and 

applicants to determine whether their actions could harm CI belugas or damage habitats essential 

to their survival and to identify measures to avoid or minimize possible adverse effects. In 

addition to MMPA and ESA reviews, activities with authorized takes are analyzed under the 

National Environmental Policy Act (NEPA). 

Research projects may be conducted at federal, state, and/or private levels. Any research that 

may take a CI beluga requires authorization under the MMPA and ESA. NMFS will continue to 

provide specific recommendations under its authorities provided by the MMPA, ESA, and 

FWCA to minimize and mitigate effects of anthropogenic actions in an effort to conserve CI 

belugas. 

c. Noise Guidelines

From what is known about the hearing sensitivity of belugas and the movements, 

distribution, and habitat use of CI belugas, the ESA and MMPA require steps be taken to 

minimize the likelihood of noise adversely impacting these whales and to minimize the 

possibility of injury or possible abandonment of critical habitats. NMFS regularly reviews and 

comments on applicable permits and recommends specific conditions to reduce or avoid 

potential impacts from noise. Mitigation measures may be incorporated into project permits to 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan B – Existing Protective Measures

IX-17

avoid incidental taking of belugas. Such taking is prohibited by the MMPA and ESA, unless 

authorized by NMFS. NMFS has developed comprehensive guidance on sound levels likely to 

cause injury to marine mammals through onset of permanent and temporary threshold shifts 

(PTS and TTS; Level A harassment) (81 FR 51694; August 4, 2016). NMFS is in the process of 

developing guidance for behavioral disruption (Level B harassment). However, until such 

guidance is available, NMFS uses the following conservative thresholds of underwater sound 

pressure levels,

36 expressed in root mean square (rms),37 from broadband sounds that cause 

behavioral disturbance, which is referred to as Level B harassment under section 3(18)(A)(ii) of 

the Marine Mammal Protection Act (MMPA): 120 dB re 1μParms for continuous sound or 160 dB 

re 1 μParms for impulsive sound. Under the PTS/TTS Technical Guidance, NMFS uses thresholds 

for underwater sounds that cause injury, which is referred to as Level A harassment under 

section 3(18)(A)(i) of the MMPA (NMFS 2016). These acoustic thresholds are presented using 

dual metrics of cumulative sound exposure level (LE) and peak sound level (PK) for impulsive 

sounds and LE for non-impulsive sounds (see NMFS 2016).

 

36 Sound pressure is the sound force per unit microPascals (μPa), where 1 pascal (Pa) is the pressure resulting from a force of one 

newton exerted over an area of one square meter. Sound pressure level is expressed as the ratio of a measured sound pressure 

and a reference level. The commonly used reference pressure level in acoustics is 1 μPa, and the units for underwater sound 

pressure levels are decibels (dB) re 1 μPa.

37 Root mean square (rms) is the square root of the arithmetic average of the squared instantaneous pressure values.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan B – Existing Protective Measures

IX-18

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Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan C – Recovery Planning for CI Belugas

IX-19

C. Recovery Planning for CI Belugas

Section 4(f) of the ESA requires NMFS to develop a recovery plan for listed species, unless 

such a plan will not promote the conservation of the species. On January 28, 2010, NMFS filed a 

notice of intent to prepare a recovery plan for CI belugas (75 FR 4528).

The Cook Inlet Beluga Whale Recovery Team (CIBRT) was appointed by NMFS’s Alaska 

Regional Administrator to assist in developing a recovery plan, and to act as an advisory group 

to identify priority recovery actions and provide input and recommendations on specific recovery 

issues. NMFS may adopt the team’s draft plan in whole or modify it. Prior to the final approval 

of any recovery plan, NMFS must provide the public with notice and an opportunity for 

comment. 

The CIBRT was composed of two advisory groups: a Scientific Panel and a Stakeholder 

Panel. The goal was to produce a science-based plan to foster recovery of the CI beluga. In 

accordance with national policy, CIBRT members were selected based on their expertise and 

ability to advance CI beluga recovery.

Given that the ability to effectively manage and recover this population requires an in-depth 

understanding of the biological and ecological processes of Cook Inlet and the CI beluga, NMFS 

relied heavily on scientists when developing the recovery plan. The Scientific Panel was 

composed of beluga experts, scientists, and co-management partners who were appointed as 

independent experts based upon their specific areas of expertise. Science Panel members did not 

represent their agency or organization while serving on the panel. The primary functions of the 

Scientific Panel were to advise NMFS about key scientific data gaps and to draft the recovery 

plan.

NMFS also recognized there is public interest in CI beluga recovery. For this reason, in 

addition to utilizing a scientific panel to draft a recovery plan, NMFS invited organizations to be 

represented on a stakeholder panel to participate in aspects of the recovery planning process. The 

Stakeholder Panel consisted of representatives of organizations with identified interests in the 

recovery of CI belugas, or those who may be affected by particular actions taken to recover CI 

belugas. The function of the Stakeholder Panel was to provide additional information to the 

Science Panel and NMFS for consideration when drafting the recovery plan. The Stakeholder 

Panel was also given the opportunity to provide feedback on interim drafts of the recovery plan 

before the CIBRT submitted its draft plan to NMFS.

The first of several CIBRT meetings took place during March 2010 in Anchorage. Following 

each meeting and prior to the next meeting, a meeting summary was posted on the NMFS Alaska 

Region’s (AKR’s) webpage dedicated to the CI beluga recovery planning process, available at:

http://alaskafisheries.noaa.gov/pr/cib-recovery-plan. Additional information on the website 

includes the CIBRT Terms of Reference, meeting dates and topics, and other recovery team and 

recovery planning documents.

The submission of a draft recovery plan to NMFS by the CIBRT in March 2013 culminated a 

three year process, and represented thousands of hours of volunteer effort from a team comprised 

of 12 Science Panelists and 19 Stakeholder Panelists. At that time, and with the thanks of 

NMFS’s Alaska Regional Administrator, the Recovery Team was disbanded and NMFS took 

responsibility for finalizing the recovery plan.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan C – Recovery Planning for CI Belugas

IX-20

NMFS reviewed the CIBRT’s draft version of the recovery plan, and made modifications 

deemed necessary to meet applicable requirements and to ensure a functional plan. Some 

modifications were minor (e.g., addition of an executive summary and a literature cited section; 

formatting the document for consistency), whereas other modifications were more substantial. 

Some of the more substantial modifications included streamlining the background section by 

moving some of the more detailed, but not necessarily essential, information to the appendices; 

adding section summaries for the different components of the background section; editing the 

threats assessment section; and modifying the list of recovery criteria and recovery actions. The 

modifications to the recovery criteria and recovery actions sections included, for example, a 

reduction in the redundancy of some criteria/actions; removal of some criteria/actions that did 

not provide a clear recovery benefit or that required a commitment of resources, authorizations, 

or continuation of programs that could not be guaranteed; an emphasis on criteria/actions 

pertaining to threats ranked as medium or high relative concern; a reassessment of some criteria 

that were not objective or measurable; and a restructuring of the list of recovery actions into a 

format that helps to focus limited resources on threats that have evidence of limiting the recovery 

of the CI beluga population. The restructuring of the recovery actions also led to a similar 

restructuring of the information presented in the implementation table. The intent of these 

revisions was to make this recovery plan a useful management document for NMFS, while also 

providing a clear path forward for others to promote the recovery of CI belugas.

NMFS announced the availability of the Draft Recovery Plan for the Cook Inlet Beluga 

Whale on May 15, 2015, and solicited public comment (80 FR 27925). During the comment 

period, NMFS received 23 unique public comment submissions from a variety of sources, 

including conservation groups, industry and industry associations, government agencies, 

scientists, Alaska Native organizations and tribal members, and interested citizens. NMFS also 

obtained independent peer review of the draft recovery plan from five reviewers not affiliated 

with the CIBRT or NMFS. NMFS considered all of the peer review and public comments and 

information received on the draft recovery plan in developing this final plan. Wherever possible, 

comments and suggestions were addressed directly as clarifications or refinements to the text. 

We also made minor updates or added information in this final plan based on scientific 

references we received or reviewed since the draft recovery plan was released.

Commenters with different interests expressed differing perspectives on certain topics that 

were in opposition to each other; in particular, they disagreed regarding the emphasis placed on 

particular threats and related recovery actions. For instance, some industry groups commented 

that certain threats ranked as medium or high relative concern (e.g., noise, catastrophic events 

such as oil spills) should not be considered as such until additional scientific data demonstrate 

those threats are clearly limiting recovery. These commenters also emphasized existing 

regulations and programs that they considered sufficient to address certain threats. In contrast, 

conservation groups and some interested citizens argued that a precautionary approach should be 

taken to address all potential threats until scientific data demonstrates that a particular threat is 

not limiting recovery. In addition, some of these commenters argued that certain threats ranked 

as low relative concern, such as pollution, should be ranked higher. Virtually all of the threat 

types identified in the plan were suggested to be of medium or high relative concern by at least 

one commenter, but some commenters expressed the view that some threats were ranked too 

high and should be downgraded. This final plan reflects updates to the background section and 

analysis of threats to include information submitted by commenters and other references that 

became available after the draft plan was released. However, after considering the available 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan C – Recovery Planning for CI Belugas

IX-21

information, we determined that the comments submitted did not provide a strong basis for 

changing the assessment of relative concern of potential threats. Therefore, in the final plan we 

continue to use this threats assessment, which NMFS has determined, based on the best scientific 

data available, will facilitate addressing threats in a manner likely to lead to recovery of the Cook 

Inlet beluga.

Given the lack of clear reasons for the failure of CI belugas to recover as expected following 

a dramatic reduction in subsistence harvest (beginning in 1999), and in an effort to avoid 

expending limited resources on actions that may have little benefit to the recovery of CI belugas, 

the plan focuses on addressing threats of medium or high relative concern. To ensure the 

recovery plan remains strategic, the status of threats ranked as low relative concern will be 

reassessed periodically to determine if the significance of one or more of those threats has 

elevated to the point that specified recovery actions need to be defined. The draft plan included 

recovery actions to improve the understanding and management of a threat, or to eliminate or 

mitigate the threat, dependent upon evidence strongly suggestive that the threat is limiting CI 

beluga recovery. In response to comments questioning that provision, we removed the proposed 

evidentiary requirement for those threat-based recovery actions, and we instead present recovery 

actions in the final plan based on the best scientific data available. In developing the final plan, 

we noted that the draft plan contained a number of proposed recovery actions that similarly 

addressed strandings, public education/outreach activities, and periodic review of the species’ 

status and threats. To reduce redundancy and simplify the plan, we consolidated the 

related/overlapping proposed recovery actions for each of these three topics, and included these 

consolidated actions within an expanded category of recovery actions that address population 

monitoring, recovery plan implementation, and public education/outreach.

Commenters also expressed differing points of view regarding certain aspects of the recovery 

criteria proposed in the draft plan, in particular the demographic criteria. While two peer 

reviewers and a few public commenters questioned the exclusion of population viability analysis 

(PVA) from the demographic criteria, conversely, the Marine Mammal Commission expressed 

the view that, given the considerable uncertainty that exists regarding PVA model inputs, basing 

the criteria on abundance thresholds and trend information is appropriate. Considerable 

uncertainty remains around some of the PVA model parameters and the existing data, and the 

sensitivity of the models to rare and unpredictable, but catastrophic events, such as mass 

strandings. Furthermore, we do not yet understand the parameters that have resulted in the failure 

of the CI beluga population to exhibit recovery following removal of the most prominent 

population-limiting threat (unregulated and unsustainable harvest). While we recognize that a 

better understanding of the factors affecting carrying capacity is also needed, we continue to 

conclude based on the best scientific data available at this time that demographic recovery 

criteria based on percent estimated carrying capacity and an abundance trend are more 

meaningful and effective for this species than the PVA approach. Eventually, as more data 

become available, a more robust PVA model and more detailed data input could be used to 

revise the recovery criteria as appropriate. A recovery action is identified in this plan to 

periodically review, and if appropriate, update a model to determine the probability of extinction 

of CI belugas, following a schedule that is compatible with the five-year update requirement for 

NMFS ESA status reviews.

We note that some commenters also questioned defining the current carrying capacity for CI 

belugas based on the historical abundance estimate of 1,300 whales. As discussed in the plan, 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan C – Recovery Planning for CI Belugas

IX-22

this is the best available estimate of historical beluga abundance in Cook Inlet, and represents the 

maximum estimate of this population based on survey data. Native subsistence harvest 

(enumerated through hunter interviews) was significant during the 1970s and 1980s and may 

have been at levels similar to the hunts reported in the mid-1990s, but there was no 

comprehensive count of subsistence harvest until the 1990s. Commercial and sport hunts also 

occurred during the 1960s and 1970s, but no information is available to assess whether the 1979 

abundance estimate of 1,293 may represent a partially depleted population, and thus a 

conservative estimate of Cook Inlet carrying capacity for belugas. While we recognize that 

carrying capacity could change, we have no data at this time to indicate whether carrying 

capacity may have increased or decreased. Therefore, in the absence of better information, 

NMFS considers the historical abundance estimate of 1,300 whales to be the carrying capacity of 

CI belugas.

After considering the comments received along with available data, we also made some 

minor changes to the threats-based recovery criteria proposed in the draft plan, including: 1) We 

refined some of the proposed criteria such that they more clearly represent progress toward 

achieving recovery; 2) We recognized that some of the proposed downlisting criteria represented 

conditions of a recovered population, so we reclassified those as delisting criteria (e.g., summer 

range has expanded to reach the documented historical range); and 3) We eliminated a few 

proposed criteria that we concluded were actions to be taken toward recovery, rather than 

indicators of recovery (e.g., an outreach program has been implemented that provides voluntary 

guidelines to reduce/avoid human-caused trauma or harassment of CI belugas).
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan D – CI Beluga Natural History Supplement

IX-23

D. CI Beluga Natural History Supplement

NOTE TO READER: The text below was developed by the CIBRT and reproduces information 

readily available in other reports. In Section II.B of this document, we provided natural history 

information sufficient to justify the recovery criteria and actions. Additional natural history 

information follows.

1. Body Size

Geographic variation in body size has been documented across the beluga’s range 

(Kleinenberg et al. 1969; Sergeant and Brodie 1969) and may be indicative of ecological 

differences, such as the availability of winter prey. Sergeant and Brodie (1969) documented a 

positive correlation between beluga size and marine productivity, with belugas in estuarine and 

Arctic waters being the smallest, whereas belugas in the subarctic were the largest. Furthermore, 

Native hunters remarked that CI belugas are larger than belugas in other parts of Alaska 

(Huntington 2000), but a systematic analysis of body size across Alaskan populations has not 

been completed. However, belugas from Cook Inlet and Bristol Bay (both estuarine areas) and 

the eastern Chukchi Sea (the high Arctic) were documented to be of similar size (Suydam 2009). 

An examination of five beluga populations of the Canadian Arctic showed that body length was 

positively correlated with latitude (Luque and Ferguson 2010), with belugas harvested at the 

highest latitude attaining the longest adult body lengths. Luque and Ferguson (2010) postulated 

that this latitudinal variation in body size may result from the seasonality of important 

environmental resources. From a preliminary analysis of a small number of specimens, Murray 

and Fay (1979) suspected there may be differences in skull morphology between CI belugas and 

other beluga populations. Similarly, differences in vocal repertoires and acoustic signatures 

among CI belugas and other Alaskan populations were investigated by Angiel (1997), but results 

are inconclusive.

2. Distribution

A review by Laidre et al. (2000) of cetacean surveys conducted from 1936 to 2000 in the 

Gulf of Alaska (Unimak Pass to Dixon Entrance) confirmed that beluga sightings are rare outside 

Cook Inlet. During dedicated surveys covering over 150,000 km (93,205 mi) of the Gulf of 

Alaska (including Cook Inlet), only five belugas (four sightings) were reported outside of Cook 

Inlet (four near Kodiak Island and one in Prince William Sound) out of over 23,000 individual 

cetacean sightings (Laidre et al. 2000). In addition to these dedicated surveys (with records of 

effort and other cetaceans seen), the NMFS Platforms of Opportunity database (data from 

surveys without defined effort) contained only 39 individual belugas (from five sightings) out of 

over 100,000 individual cetaceans sighted (Laidre et al. 2000). Other incidental sightings from 

1936 and 2000 (from commercial or recreational fishing boats, tourists, and bird surveys with no 

information about survey effort or other cetaceans seen) documented over 260 individual belugas 

(from approximately 19 sightings) (Laidre et al. 2000), with only 28 sightings of belugas outside 

of Cook Inlet (nine near Kodiak Island, 10 in or near Prince William Sound, eight in Yakutat 

Bay, and one sighting well south of the Gulf of Alaska).

3. Age Determination

There has been recent discussion about the deposition rate of growth layer groups (GLGs) in 

beluga teeth (Figure D1), including questions on whether belugas produce one or two GLG per 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan D – CI Beluga Natural History Supplement

IX-24

Notes: Photo of a beluga whale tooth cross section showing the pulp cavity at the left and progressive layers of dentin towards the right. The 

oldest dentin layers are on the outer margins of the tooth with progressively thinner layers of dentin deposited in later years near the central pulp 

cavity. Each layer is considered a growth layer group and is used for aging the individual.

Source: The North Atlantic Marine Mammal Commission; image acquired 24 July 2013 from report of the workshop on age estimation in 

monodontids at: http://www.nammco.no/publications/scientific-committee-reports/report-of-the-19th-meeting-of-the-nammco-scientificcommittee/report-of-the-workshop-on-age-estimation-in-monodontids/.

Figure D1. Photo of beluga tooth cross section.

year. The initial hypothesis was that two GLGs were deposited annually (Sergeant 1959), which 

was supported by many successive studies (Brodie 1971, 1982; Sergeant 1973; Burns and 

Seaman 1986; Goren et al. 1987; Brodie et al. 1990; Heide-Jørgensen et al. 1994). This 

deposition rate was previously assumed for most odontocetes. Although further investigation 

revealed that other odontocetes deposited only one GLG per year, the notion of two GLGs per 

year persisted for belugas. After re-evaluation of previous studies, analyses of teeth of two 

captive belugas, and examination of tetracycline-marked teeth, several studies concluded that 

belugas deposited only one GLG per year (Hohn and Lockyer 1999; Stewart et al. 2006; Lockyer 

et al. 2007; Luque et al. 2007; NAMMCO 2011). Deposition of a single GLG per year among 

belugas would double most of the previous estimates of age, with associated changes to vital 

rates (such as longevity, age at sexual and physical maturity, age at first birth, etc.). Here, it is 

assumed that one GLG is deposited annually and some of the estimates in Table 1 have been 

revised to reflect this change.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-25

E. CI Beluga Hearing, Vocalization, and Noise Supplement

NOTE TO READER: The text below was developed by the CIBRT and reproduces information 

readily available in other reports. In Sections II.B.6 and III.A.3 of this document, we provided 

information sufficient to justify the recovery criteria and actions addressing noise. Additional CI 

beluga hearing, vocalization, and noise information follows.

1. Beluga Hearing

Having evolved from land based mammalian ancestors, cetaceans have inherited an ear that 

was first adapted to hearing sounds through air, which then readapted to receiving sounds 

through water (Thewissen and Hussain 1993). Cetaceans have retained the ear drum, ossicles, 

Eustachian tube, and middle ear structures, including an air-filled cavity within the temporal 

bone or bulla, connected by the Eustachian tube to the nasal cavity for equalization of pressure 

during dives (Gingerich et al. 1983; Thewissen and Hussain 1993; Ridgway et al. 2001). As a 

consequence, it was hypothesized that cetacean hearing might attenuate at depth due to the 

increased air pressure and density of air in the middle ear, which might make them less 

susceptible to the impacts of loud underwater sounds. This has been shown not to be the case in 

belugas, as their hearing was determined to be as good at 300 m (984 ft) depth as at the surface 

(Ridgway et al. 2001). This is consistent with the theory that sound may be received through 

odontocetes’ lower jaw “acoustic window” and transmitted directly to the ear (Norris 1968; 

Cranford et al. 2008). In fact, a study conducted with a captive beluga showed that the most 

efficient hearing pathway is from the rostrum tip (Figure E1), and may indicate that there are 

acoustic fat channels that begin at the beluga rostrum tip that effectively guide sound to the inner 

ear (Mooney et al. 2008). To date, belugas are the only odontocetes known to hear from the 

rostrum tip, although a similar pathway has been recently proposed for Cuvier’s beaked whale 

(Cranford et al. 2008). This feature probably gives belugas greater directional hearing abilities

than other odontocetes. It is possible that belugas’ unfused vertebrae, which allows for a highly 

movable head, facilitates increased hearing directionality.

2. Beluga Echolocations and Vocalizations

Belugas utilize an alternative echolocation strategy compared with the bottlenose dolphin 

when performing identical echolocation tasks (Turl and Penner 1989; Rutenko and Vishnyakov, 

2006). Bottlenose dolphins will emit a click and wait until the echo returns before emitting the 

next signal (i.e., the inter-click interval is always greater than the two-way time travel). Belugas 

appear to be able to transmit, receive, and process signal packets simultaneously, with the first 

click about two dB higher than the other clicks that follow, which may serve to identify the 

beginning of each signal packet (Turl and Penner 1989).

The first vocal repertoire description of belugas was made in the Canadian high Arctic by 

Sjare and Smith (1986a). They classified a total of 807 tonal calls (whistles) into 16 contour 

types and some 436 pulsed calls into three major categories that they describe as “click series,” 

“pulsed tones,” and “noisy vocalizations.” Subsequent studies have obtained varied results. The 

vocalizations of adult male beluga groups in Svalbard, Norway, were subjectively classified into 

21 call types, which were dominated by a variety of whistles (Karlsen et al. 2002). Karlsen et al. 

(2002) highlighted the highly graded nature of these beluga calls, as one “call type” can merge 

into another type with very subtle changes, making the classification very challenging. A
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-26

Notes: 1, location of active Auditory Evoked Potential electrode; 2, rostrum tip; 3, pan bone; 4, external auditory meatus; 5, behind meatus; 6, 

melon. Thresholds are presented in dB re 1 μPa using p-p SPLs measured at 1 m. 

Source: Mooney et al. 2008.

Figure E1. Diagram of beluga’s head for electrophysiological hearing tests with points of acoustic stimulation.

reproductive gathering of belugas in the White Sea, Russia, has been the subject of several 

repertoire studies (Belikov and Bel’kovich 2001, 2003; Bel’kovich and Kreichi 2004; Belikov 

and Bel’kovich 2007, 2008). Whistle-like signals were found to comprise approximately 10% of 

the total vocal production of this whale group. Of these, 750 signals were divided into 43 classes 

(Belikov and Bel’kovich 2001) with at least 16 whistle types (Belikov and Bel’kovich, 2007) and 

vowel-like signals and pulsed signals (Bel’kovich and Kreichi 2004; Belikov and Bel’kovich 

2008). 

The response of a decrease or cessation in acoustic activity has been observed in both captive 

and free-ranging belugas (Morgan 1979; Lesage et al. 1999; Karlsen 2002; Van Parijs et al.

2003; Castellote and Fossa 2006) and free-ranging narwhals (Finley 1990); the response has 

been associated with threat, startle, fright, alarm, or stress contexts and interpreted as a survival 

strategy to avoid detection by predators (Schevill 1964; Fish and Vania 1971; Morgan 1979;

Finley 1990; Lesage et al. 1999). A broad band pulsed call labelled “Type A” (Vergara and 

Barrett-Lennard 2008) was identified as a contact call between mothers and their calves in a 

captive environment. It is thought that these calls, both in captivity and in the wild, function to 

maintain group cohesion, and the variants shared by related animals are used for mother-calf 

recognition (Vergara et al. 2010). The only study on vocal development in belugas suggests that 

neonates only produce pulse trains before they acquire rudimentary whistles at two weeks of age 

(Vergara and Barrett-Lennard 2008), although this is based on observations of one captive male 

beluga calf. Similarly, sound production of another neonate captive beluga consisted exclusively 

of low-frequency, short duration pulse trains that were not part of the adult’s repertoire 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-27

(Castellote et al. 2007). Despite differences in populations of origin, captive facilities, health, and 

in acoustic context, the sound production observed in these two neonate belugas suggests a 

species-specific pattern of developmental stages in sound acquisition. Whether these observed 

captive neonate vocalization characteristics may prove useful in detecting the presence of wild 

neonates is still to be determined.

The most recent study on beluga social signals (Vergara et al. 2010) emphasized the two 

persistent problems commonly encountered in the study of animal communication: first, the 

great variability in the physical features of the sounds, with general call types grading into each 

other (Recchia 1994), introduces great uncertainty in the categorization schemes; second, the 

inherent difficulty in categorizing sounds that are biologically meaningful without testing how 

belugas themselves perceive or use them (Tyack and Clark 2000). Despite the challenges, some 

progress has been made in the attempt to correlate vocalization rate and call type with specific 

beluga behavioral states. 

3. Effects on Beluga Hearing and Behavior from Anthropogenic Noise

There is an extensive body of literature regarding the effect of anthropogenic noise on marine 

mammal behavior. Most of the studies addressing this problem have used behavioral attributes 

such as changes in site fidelity, dive patterns, swimming speed, orientation of travel, herd 

cohesiveness, and dive synchrony to indicate possible disturbance or stress caused by noise 

(Richardson et al. 1995). However the current knowledge of the effects of anthropogenic noise to 

marine mammal acoustic behavior is more limited, and only a few studies have focused on 

belugas.

Their high auditory sensitivity, wide frequency bandwidth, and dependence upon sound to 

navigate, communicate, and find prey make belugas vulnerable to noise pollution. Noise 

pollution may mask beluga signals, or if intense, may lead to temporary or permanent hearing 

impairment (Awbrey et al. 1988; Finley 1990; Green et al. 1994; Richardson et al. 1995, 1988). 

Exposure to intense sound can produce an elevated hearing threshold, referred to as a threshold 

shift (TS). If the threshold later returns to normal it is considered a temporary threshold shift 

(TTS), but if not, it is considered a permanent threshold shift (PTS). Studies of TTS and PTS 

have helped to establish noise exposure limits in humans. There are no PTS data for cetaceans, 

yet a few studies have attempted to establish the TTS for belugas (Finneran et al. 2000, 2002a; 

Schlundt et al. 2000). Finneran et al. (2000) simulated sounds resembling signatures of 

underwater explosions from 5 or 500 kg HBX-1 charges at ranges from 1.5 to 55.6 km (0.9–34.5 

mi), and while the simulated sounds were not intense enough to affect the beluga hearing 

capabilities, sound levels simulating explosions of 500 kg (1,102 lb) at 1.9 km (1.2 mi) and 

closer did disrupt the behavior of the belugas. However, they found no TTS after exposure to the 

highest level the underwater sound projector could produce. Finneran et al. (2002a) reported 

behaviorally measured TTS in a bottlenose dolphin and a beluga exposed to single pulses from a 

seismic water gun. Also, Schlundt et al. (2000) performed a study exposing five bottlenose 

dolphins and two belugas (same individuals as Finneran’s studies) to intense 1 second tones at 

different frequencies. The resulting levels of fatiguing stimuli necessary to induce 6 dB or larger 

masked TTSs were generally between 192 and 201 dB re 1 microPascal (μPa). Dolphins began 

to exhibit altered behavior at levels of 178–193 dB re 1μPa and above; belugas displayed altered 

behavior at 180–196 dB re 1 μPa and above. At the conclusion of the study, all thresholds were 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-28

at baseline values. Results of this study indicate that at least these two odontocetes species are 

susceptible to TTS, but that they seem to recover from at least small levels of TTS. 

A number of studies have examined other characteristics of beluga hearing. Johnson (1991) 

analyzed hearing thresholds, bandwidths, and integration times (basic descriptive parameters of 

the cetacean sonar system) for single pulsed tones and multiple pulsed tones of 60 kHz in the 

presence of noise. He found negative correlations between hearing thresholds and pulse 

repetition rate with abrupt 5–6 dB steps, and linear correlations between pulse repetition rate and 

integration times. The author related the abrupt hearing steps to a change in the echolocation 

strategy based on target distance, as has been described in some beluga echolocation studies, and 

is discussed in the next section. This result, together with a variable integration time and a 

constant system bandwidth of 1,000 Hz (much lower than previously reported), led the author to 

suggest that beluga sonar systems could not be fully described by a single filter model. In 

essence, this conclusion was a technical appreciation of the complexity of the beluga biosonar 

system. Finneran et al. (2002c) analyzed beluga sensitivity to acoustic particle motion, which is 

one of the two physically linked components of sound in water (together with pressure waves), 

and the main feature detected by all fish species (Fay and Popper 1975). Results suggested that 

the two belugas tested responded to changes in the acoustic pressure alone and were not able to 

use acoustic particle motion cues.

The possibility that noise conditions might mask the ability of animals to hear and decipher 

specific sounds has been studied in belugas in order to understand the potential impacts of 

anthropogenic noise on belugas. When a tonal signal is played in a broad spectrum of white 

noise (noise with equal loudness across all frequencies), only the noise energy in a relatively 

narrow band on either side of the tone frequency is effective in masking the signal, and the rest 

of the noise spectrum contributes little or nothing to the masking effect. Johnson et al. (1989) 

analyzed this feature in the hearing of a beluga in a wide frequency range (40–115 kHz) and 

found that the whale’s ability to detect the signal in noise was slightly better than results 

previously reported for bottlenose dolphins. Erbe et al. (1999) and Erbe (2000) analyzed the 

effect of masking of beluga calls by exposing a trained beluga to icebreaker propeller noise, an 

icebreaker’s bubbler system, and ambient Arctic ice cracking noise, and found that the latter was 

the least problematic for the whale detecting the calls. Finneran et al. (2002b) analyzed the 

ability of a beluga to detect acoustic signals in noise. A primary feature of the auditory system in 

these animals is the ability to resolve a complex sound into its individual frequency components 

by a set of auditory filters, and the filter shape and size affect the loudness and detectability of 

complex sounds and broadband signals (Scharf 1970). The authors analyzed 20 and 30 kHz puretone underwater hearing thresholds in one beluga and two bottlenose dolphins in the presence of 

broadband noise at two intensities: 90 and 105 dB re 1 μPa2

/Hz. The filter shapes obtained for 

the dolphins and beluga were similar, but the filter width was consistently smaller for the beluga, 

conferring better ability to detect acoustic signals in noise.

Sheifele et al. (2005) studied a population of belugas in the SLE to determine whether beluga 

vocalizations showed intensity changes in response to shipping noise. This type of behavior has 

been observed in humans and is known as the Lombard vocal response (Lombard 1911). Sheifele 

et al. (2005) demonstrated that shipping noise did cause belugas to vocalize louder (Figure E2). 

The acoustic behavior of this same population of belugas was studied in the presence of ferry and 

small boat noise. Lesage et al. (1999) described more persistent vocal responses when whales 

were exposed to the ferry than to the small-boat noise. These included a progressive reduction in 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-29

calling rate while vessels were approaching, an increase in the repetition of specific calls, and a 

shift to higher frequency bands used by vocalizing animals when vessels were close to the 

whales. The authors concluded that these changes, and the reduction in calling rate to almost 

silence, may reduce communication efficiency, which is critical for a species of a gregarious 

nature. However, the authors also stated that, because of the gregarious nature of belugas, this 

“would not pose a serious problem for intraherd communication” of belugas given the short 

distance between group members; the authors further concluded a noise source would have to be 

very close to potentially limit any communication within the beluga group (Lesage et al. 1999).

The fact that SLE belugas alter their vocal behavior by increasing the intensity or repetition 

rate, or by shifting to higher frequencies when exposed to shipping noise (from merchant, whalewatching, ferry and small boats), is indicative of an increase of energy costs (Bradbury and 

Vehrencamp 1998). If noise exposure is chronic, long-term adverse energetic consequences 

could occur for belugas, as it has been shown for birds (Oberweger and Goller, 2001). Chronic 

noise exposure could also increase stress levels for CI belugas, as has been shown in North 

Atlantic right whales (Rolland et al. 2012). Definitively linking adverse energetic consequences 

and chronic stress responses to detrimental health effects in belugas or other cetaceans is 

extremely difficult because of the logistics of studying free-swimming whales and the inability to 

conduct a controlled study. However, a large body of literature has demonstrated that chronic 

stress can lead to detrimental effects on health and reproduction across a variety of vertebrate 

taxa (Rolland et al. 2012). Both the degradation of the beluga acoustic communication and 

echolocation space, as well as the noise-induced chronic increase of signaling costs and stress, 

could lead to negative biological consequences at the population level. Even if these 

consequences are not yet well understood, there is sufficient evidence to suggest that the 

reproductive success and survival of cetaceans can be negatively impacted by noise (NRC 2000, 

2003, 2005; Cox et al. 2006; Southall et al. 2007; Clark et al. 2009; Payne and Webb 1971; 

Tyack and Clark 2000).

While exhibiting a Lombard response provides a mechanism for animals to cope with 

varying levels of noise, the need for and use of this response suggests that the animal is 

attempting to cope with noise levels that are near a point where masking will occur. The effect of 

shipping noise in the acoustic environment of the endangered SLE beluga was studied recently 

by Gervaise et al. (2012) in the lower SLE. Noise from a car ferry line as well as a seasonal 

whale watching fleet were analyzed. The study found both beluga communication and 

echolocation bands were dramatically affected by these noise sources. Based on the background 

noise levels, spectra, and periodicity reported and based on the assumption of no behavioral or 

auditory compensation, beluga communication and echolocation signals could be masked 50% of 

the time with a reduction of potential communication ranges to less than 30% of their values 

under natural ambient noise conditions. Similarly, echolocation could be reduced to 80% of their 

range under natural ambient noise conditions. The study concludes that noise from these sources 

could easily limit long-range communication (in the order of 1–2 mi [1.6–3.2 km]) among 

scattered individuals or pods and affect echolocation efficiency in all exposed belugas. 

There are some documented beluga spatial displacements caused by loud sources of noise. 

Two different research teams and data from several years showed that belugas typically avoided

icebreakers at distances of 35–50 km (22–31 mi), at the point where they could probably just 

detect them. They travelled up to 80 km (50 mi) from the ship track and usually remained away
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-30

Notes: Beluga signals are louder when background noise level is higher. 

Source: Scheifele et al. 2005.

Figure E2. Regression of beluga vocalization level versus changing noise levels from extracted beluga 

vocalizations in the presence of noise. 

for 1–2 days (Finley et al. 1990, Cosens and Dueck 1993). When drilling sounds were played to 

belugas in industry-free areas, the belugas only showed a behavioral reaction when received 

levels were high (Richardson et al. 1997). Belugas have been observed to show startle responses 

when drilling noises were played with a received level greater than or equal to 153 dB re 1 μPa. 

Considerable displacements have also been suggested for noise from air guns typically used 

during seismic surveys. One seismic survey in the Canadian Beaufort Sea determined behavioral 

reactions of belugas occurred when two 24 gun arrays of 2,250 in3 were operating (Miller et al. 

2005). Results of the analysis of the differences between vessel-based and aerial-based beluga 

sighting distributions provided evidence of reactions of belugas to seismic operations at distances 

above 20 km (12.4 mi), beyond the effective visual range of the MMOs on the seismic vessel 

(Miller et al. 2005). Aerial surveys conducted in the southeastern Beaufort Sea in summer found 

that sighting rates of belugas were significantly lower at distances of 10–20 km compared with 

20–30 km from an operating airgun array (Miller et al. 2005). The low number of beluga 

sightings by marine mammal observers on the vessel seemed to confirm there was a strong 

avoidance response to the 2250 in3 airgun array; however, it is unclear if the observed movement 

of the belugas was a direct consequence of the seismic surveys or related to the natural offshore 

migration at that time of year. More recent seismic monitoring studies in the same area seem to 

confirm that the apparent displacement effect on belugas extends farther than has been shown for 

other small odontocetes exposed to airgun pulses (e.g., Harris et al. 2007).

Similarly, aerial survey results from another seismic (array specifications unknown) and 

exploratory drilling activity conducted in the same area and same season in 2007 to 2008 showed 

belugas widely distributed offshore during the operation period, yet rarely sighted from seismic 

ships. This was interpreted as a tendency to temporarily avoid areas of seismic activity by greater 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-31

distances than the range covered by MMOs on board seismic vessels (Harwood et al. 2010). 

However, the authors highlighted the temporary nature of these displacements, as belugas were 

observed back in the seismic operation area within days after the end of the seismic operations.

Belugas have been shown to have greater displacement in response to a moving sound source 

(e.g., air gun activity on a moving vessel) and less displacement or behavioral change in response 

to a stationary sound source. The presence of belugas has been documented within ensonified 

zones of industrial sites near platforms and stationary dredges, and the belugas did not seem to 

be disturbed by the activity (Richardson et al. 1995).
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan E – CI Beluga Hearing, Vocalization, and Noise Supplement

IX-32

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Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-33

F. CI Beluga Prey Supplement

NOTE TO READER: The text below was developed by the CIBRT, with a few minor updates, and 

reproduces information readily available in other reports. Additional details regarding the State 

of Alaska’s fisheries management practices and fisheries harvest information can be found in 

ADF&G publications, such as annual commercial fisheries management reports (e.g., Shields 

and Dupuis 2016).38 In Sections II.B.10 and III.A.6 of this document, we provided information 

sufficient to justify recovery criteria and actions addressing CI beluga prey. Additional CI 

beluga prey information follows.

1. Prey Abundance and Distribution

Eulachon is a primary prey item of CI belugas from May to early June. They enter glacial 

rivers to spawn shortly after the river ice has melted and the water flows freely. Eulachon have 

high oil-content (17–21% of the wet weight; Payne et al. 1999) and migrate in dense schools. 

Large eulachon runs in Cook Inlet occur in the Susitna River and at Twenty Mile River in 

Turnagain Arm, with smaller runs in other glacial rivers entering Cook Inlet (Figure F1). 

Eulachon biomasses in these rivers are unknown. The NMFS biennial bottom trawl survey 

estimates of eulachon biomass in the central Gulf of Alaska are highly variable (5,255 short tons 

in 1984, 104,709 tons in 2003, and 54,246 tons in 2011) (Ormseth 2011). In the Susitna River 

and Twenty Mile River, the eulachon spawning migration peaks in late May and is largely 

completed by mid-June (Barrett et al. 1984; Spangler et al. 2003). Commercial fishing for 

eulachon/smelt (eulachon are not distinguished from other smelt in ADF&G harvest reporting) 

occurs annually in saltwater between the mouths of the Chuitna and Susitna rivers (Figure F1). 

Harvests have ranged from 41–97 metric tons (45–107 short tons) since 2006 (Table F1) (Shields 

and Dupuis 2016). Commercial harvest of eulachon has increased substantially in recent years 

(Table F1).

Personal use harvests in Cook Inlet are summarized by ADF&G Division of Sport Fish 

reporting areas (Figure F2). Although fishing effort for personal use harvests of smelt responds 

to socioeconomic variables (e.g., gasoline prices), recreational effort likely reflects population 

abundance of spawning smelt. Thus, strong spawning returns likely generate increased fishing 

effort such that recreational harvests index the relative magnitude of the spawning populations. 

Recreational harvests for Cook Inlet during 1996 to 2011 showed high interannual variability 

within and among harvest reporting areas (Figure F3). Although the late 1990s and mid-2000s 

exhibited generally higher smelt harvests, the correlation of annual harvests among reporting 

areas was relatively low (the maximum correlation was 0.50 between log transformed values for 

the Susitna River drainage and the Kenai Peninsula freshwater). In general, the largest personal 

use harvests occurred in the Anchorage area, mainly represented by Twenty Mile River in 

Turnagain Arm. Harvests in most areas increased in recent years, particularly for the Anchorage 

area.

From June to September, salmon are the primary beluga prey in Cook Inlet. Quakenbush et 

al. (2015) found primarily coho, chum, and Chinook salmon in analyses of salmon remains in 

 

38 For more information, visit ADF&G’s website at: http://www.adfg.alaska.gov/index.cfm?adfg=home.main.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-34

Table F1. Commercial eulachon/smelt harvests in Cook Inlet.

Year

Harvest

Pounds Metric tons Permits issued

1978 300 0.1 NA

1980 4,000 1.8 NA

1998 18,610 8.4 2

1999 100,000 45.4 NA

2006 90,783 41.2 8

2007 125,044 56.7 11

2008 127,365 57.8 6

2009 78,258 35.5 6

2010 126,135 57.2 3

2011 201,570 91.4 5

2012 195,910 88.9 4

2013 190,830 86.6 4

2014 198,814 90.2 4

2015 213,934 97.0 4

Source: Shields and Dupuis 2016.

stomach contents, indicating that some salmon species may be of greater importance (Table 2). 

During this period, belugas are often found from Tyonek to the Little Susitna River and in river 

mouths of Knik and Turnagain arms. The largest salmon runs in Cook Inlet enter the Kenai, 

Kasilof, and Susitna rivers. Chinook salmon runs peak in the Susitna and Little Susitna rivers in

mid-June, in the Kenai River in mid-July, and in the Kasilof River in late June to early July 

(Figure F4). Sockeye salmon runs typically peak in mid-July, pink salmon and chum salmon runs 

peak in late July or early August, and coho salmon runs peak in August (Figure F4). However, 

run timing differs among species, streams, and years.

Sockeye salmon are the dominant species in the Kenai and Kasilof rivers with significant 

numbers of Chinook, coho, and pink salmon also spawning in the Kenai River. The Chuitna, 

Beluga, Theodore, and Lewis rivers support relatively small runs of Chinook salmon and 

somewhat larger runs of coho salmon (Figure F5). The Susitna River drains the largest watershed 

entering Cook Inlet and supports substantial runs of all five salmon species (Figure F5). The 

Little Susitna River supports moderately sized runs of pink, chum, and coho salmon (Figure F5). 

Numerous small streams along Knik and Turnagain arms support relatively small runs of all five 

salmon species.

Indices for upper Cook Inlet since the early 1970s show general increases in sockeye and 

coho salmon return abundances, an odd/even year cycle in pink salmon abundances, and a 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-35

Source: Shields and Dupuis 2012.

Figure F1. Major tributaries of the Cook Inlet Basin relative to the two fishery management district 

boundaries.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-36

Source: ADF&G website at: http://www.adfg.alaska.gov.

Figure F2. Cook Inlet reporting areas for the ADF&G statewide survey of recreational and personal use 

harvests.

Source: Adapted from ADF&G Alaska Sport Fishing Survey website at: http://www.adfg.alaska.gov/sf/sportfishingsurvey.

Figure F3. Personal use harvest of smelt (eulachon) by reporting areas from the ADF&G statewide harvest 

survey, 1996 to 2011.

0

10

20

30

40

50

60

1996199719981999200020012002200320042005200620072008200920102011

Thousands of FIsh

Year

Anchorage

Knik Arm

Susitna River

West Cook Inlet

Kenai Peninsula Fresh

Kenai Peninsula Salt
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-37

Source: Westerman and Willette 2010.

Figure F4. Mean run timing of sockeye, pink, chum, Chinook, and coho salmon entering the Kenai, Kasilof, Susitna, and Little Susitna Rivers, 1982 to 

2009.

0.00

0.02

0.04

0.06

0.08

0.10

5/20 5/30 6/9 6/19 6/29 7/9 7/19 7/29 8/8 8/18 8/28 9/7 9/17 9/27

Susitna River

0.00

0.02

0.04

0.06

0.08

0.10

5/20 5/30 6/9 6/19 6/29 7/9 7/19 7/29 8/8 8/18 8/28 9/7 9/17 9/27

Little Susitna River

0.00

0.02

0.04

0.06

0.08

0.10

5/20 5/30 6/9 6/19 6/29 7/9 7/19 7/29 8/8 8/18 8/28 9/7 9/17 9/27

Kenai River

0.00

0.02

0.04

0.06

0.08

0.10

5/20 5/30 6/9 6/19 6/29 7/9 7/19 7/29 8/8 8/18 8/28 9/7 9/17 9/27

Kasilof River

Daily Proportion of Total Count

Sockeye Pink Chum Chinook Coho

Calendar Date
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-38

Figure F5. Historical mean in-river abundances of Chinook, sockeye, coho, pink, and chum salmon entering 

the major Rivers flowing into Cook Inlet.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-39

Notes: The commercial drift gillnet fishery catch per unit effort indicates annual deviations from long-term mean catch after standardizing for fishing time and gear length. Abundance estimates 

represent offshore test fishery catches extrapolated to total run size assuming equal catchability among species (Shields and Willette 2010; M. Willette, ADF&G, pers. comm.). For comparison, markrecapture estimates of coho and chum salmon run sizes are shown as black dots for 2002.

Source: Willette et al. 2003.

Figure F6. Trends in abundance indices for sockeye, coho, pink, and chum Salmon returns to upper Cook Inlet, 1966 to 2012. 

0

2

4

6

8

10

12

14

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

1965 1975 1985 1995 2005 2015

Abundance (millions) 

CPUE 

Sockeye Salmon

0

1

2

3

4

5

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1965 1975 1985 1995 2005 2015

Abundance (millions)

CPUE 

Coho Salmon

0

1

2

3

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

1965 1975 1985 1995 2005 2015

Abundance (millions) 

CPUE 

Pink Salmon

0

1

2

3

4

5

6

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

1965 1975 1985 1995 2005 2015

Abundance (millions)

CPUE 

Chum Salmon 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-40

decline in chum salmon abundances (Figure F6). Sockeye salmon run sizes, indexed as catches 

and escapements into major river systems, increased primarily due to larger returns to the Kenai

and Kasilof rivers. Pink, coho, and chum salmon indices, derived from test fishery catches,

provide temporal trends, but give only an order of magnitude indication of abundances. Markrecapture abundance estimates for coho and chum salmon are more accurate, but are only

available for 2002. Although commercial drift gillnet catch per unit effort is based on harvests by 

several hundred boats and test fishery estimates are based on catches of a single boat, these 

indices show similar trends (Figure F6).

Commercial salmon catches in northern Cook Inlet (above the Forelands), where belugas 

have concentrated in recent years, were relatively low in the late 1960s and early 1970s, 

relatively high in the 1980s, and have subsequently declined (Figure F7). This catch decline is 

partly attributed to fisheries management constraints on fishing effort in order to increase 

escapements of primarily Chinook, sockeye, and coho salmon. Although salmon returns to the 

major river systems of northern Cook Inlet have exhibited broad swings in return abundance, 

many stocks and systems have shown declines in recent years. Sonar estimates of total salmon 

entering the Yentna River (a Susitna River tributary) ranged from about 0.4 to 1.6 million fish,

with no clear temporal trend during 1982 to 2009 (Figure F8). However, the contribution of most 

species to fish wheel catches in the Yentna River declined as the run was increasingly comprised 

of pink salmon after 2005 (Figure F8). Chinook and coho salmon weir counts on the Deshka 

River (a major tributary of Susitna River) and coho salmon weir counts on Little Susitna River 

peaked in 2004 and have since declined (Figure F9). Sockeye salmon weir counts on Fish Creek 

(Knik Arm) have been weak in some recent years, but the 2010 weir count was the highest since 

1985 before declining dramatically in 2011 and 2012. Coho salmon entering Jim Creek (Knik

Arm) increased from the late 1990s to 2006, but have decreased since 2008 (S. Ivey, ADF&G, 

pers. comm.; Figure F9).

An important concern is that salmon are an essential feature of CI beluga critical habitat, and 

some species of salmon, most notably Chinook, have had reductions in run strength in Cook Inlet

and throughout Alaska. Responding to a request from Alaska Governor Sean Parnell, Acting 

U.S. Secretary of Commerce Rebecca Blank determined that commercial fishery failures due to 

fishery resource disasters had occurred for Chinook salmon stocks in the Yukon (2010, 2011, 

2012), Kuskokwim (2011, 2012), and Cook Inlet (2012) regions.

39 The declaration 

acknowledged hardships for commercial, sport, and subsistence users as a result of the Chinook 

fishery failures. To identify key knowledge gaps and discuss how best to address those gaps, 

ADF&G sponsored a Chinook salmon symposium, “Understanding the Abundance and 

Productivity Trends of Chinook Salmon in Alaska,” in Anchorage during October 22–23, 

2012.

40 Subsequently, ADF&G worked collaboratively with federal agencies and academic 

partners to develop a stock assessment and research plan with recommended studies to address 

critical knowledge gaps (ADF&G Salmon Research Team 2013).

 

39 See news release at: http://www.nmfs.noaa.gov/stories/2012/09/09_13_12disaster_determinations.html; A copy of the letter 

from Acting Secretary Blank to Governor Parnell can be viewed at: 

http://www.nmfs.noaa.gov/stories/2012/09/docs/blank_parnell_9_13_12.pdf.

40 For more information about the Chinook salmon symposium, visit ADF&G’s website at: 

http://www.adfg.alaska.gov/index.cfm?adfg=chinook_efforts_symposium.information.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-41

Northern pike were not found in any Cook Inlet streams until being illegally introduced in 

the 1960s. The spatial distribution of pike has since expanded to include many northern Cook 

Inlet streams and lakes. In the Susitna watershed, invasive northern pike have impacted many 

salmonid populations (e.g., Alexander Creek, Shell, and Hewitt lakes) and have largely 

eliminated salmon from some lakes (e.g., Trapper, Red Shirt, Sucker, and Caswell). The capture 

of northern pike by commercial salmon fishermen in upper Cook Inlet waters also indicates a 

potential expansion to other watersheds. Although we do not know to what extent salmon 

production in Cook Inlet has been impacted by northern pike, pike have clearly reduced salmon 

production in some areas.

Prior to 1990, belugas were often found in central and lower Cook Inlet, but it is not known 

what prey were consumed in these areas. In the 1970s, Kamishak Bay supported large 

commercial catches of Tanner and red king crabs, and summer concentrations of Pacific halibut 

were found north of Augustine Island (NOAA 1977; Bechtol et al. 2002). While commercial 

fisheries have not occurred since the early 1980s for red king crab and the early 1990s for Tanner 

crab, Pacific halibut still support fisheries extending north into central Cook Inlet (Meyer et al. 

2008). In spring, Pacific herring aggregate in shallow, nearshore areas of Kamishak Bay to 

spawn. Peak biomass reached 35,513 short tons in 1983 (Figure F10), declined to 2,906 tons in 

2004, and has subsequently ranged from 3,100 to 4,100 tons (Otis and Hammarstrom 2004; 

Hammarstrom and Ford 2011; Hollowell et al. 2012). Due to low spawning biomass, the 

commercial herring fishery in lower Cook Inlet has remained closed since 1999. Although 

herring resources in upper Cook Inlet are not formally assessed, low-level commercial fisheries 

occur, with annual harvests generally totaling less than 20 tons over the past 15 years (P. Shields, 

Source: Shields and Dupuis 2012; M. Willette, ADF&G, pers. comm.

Figure F7. Commercial salmon catch (numbers of fish) and fishery effort (permit-hours) in the Cook Inlet 

Northern District, 1966 to 2012.

0

5,000

10,000

15,000

20,000

25,000

0

200,000

400,000

600,000

800,000

1,000,000

1966196919721975197819811984198719901993199619992002200520082011

Effort (permit-hours)

Harvest Abundance

Year

Sockeye Pink Chum Chinook Coho Effort
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-42

Source: Westerman and Willette 2010.

Figure F8. Sonar estimates of total salmon return entering the Yentna River (a Susitna River tributary) and 

fish wheel catch composition at the sonar site, 1982 to 2009.

Fish Wheel Catch Composition

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1980 1985 1990 1995 2000 2005 2010

Proportion 

Sockeye Coho Pink Chum

Total Salmon Abundance

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

1980 1985 1990 1995 2000 2005 2010

Abundance 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-43

Notes: Little Susitna weir counts for species other than coho salmon are uncertain because the weir was moved to a different upstream location in 1996 and the weir operations did not always encompass 

the entire run (Sweet et al. 2003). 

Source: ADF&G Fish Counts webpage at: http://www.adfg.alaska.gov/sf/FishCounts/; S. Ivey, ADF&G, pers. comm.; M. Willette, ADF&G, pers. comm.

Figure F9. Salmon run sizes entering the Little Susitna River, Deshka River, Fish Creek, and Jim Creek, 1985 to 2012.

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

198519901995200020052010

Abundance

Little Susitna River

(weir)

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

198519901995200020052010

Abundance

Deshka River

(weir)

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

198519901995200020052010

Abundance

Fish Creek

(weir)

0

5,000

10,000

15,000

20,000

25,000

198519901995200020052010

Abundance

Jim Creek

(ground + inriver harvest)

 

Sockeye Pink Chum Chinook Coho
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-44

Source: Otis and Hammarstrom 2004, Hollowell et al. 2012.

Figure F10. Historical biomass (short tons) of spawning Pacific herring in Kamishak Bay, 1981 to 2010.

ADF&G, pers. comm.). At Chisik Island, large shallow schools of eulachon, herring, and 

crangonid and pandalid shrimps were found in May 1997 and 1998, while lower density schools 

of herring, eulachon, and longfin smelt were found deeper in this area during summer (Fechhelm 

et al. 1999). Piatt (2002) found cold, nutrient-rich Gulf of Alaska waters upwelling at the 

entrance to lower Cook Inlet supported high densities of juvenile pollock, sandlance, and capelin. 

Demersal fish resources in this area were dominated by walleye pollock, Pacific cod, butter sole, 

and Pacific halibut (Blackburn et al. 1980).

Historically, belugas were often observed in the fall along the northern shore of Kachemak 

Bay. Pacific sandlance, which spawn on beaches in the fall, were the most abundant nearshore 

fish species found in Kachemak Bay (Robards et al. 1999), but it is unknown if these fish were 

beluga prey. An abundant shallow subtidal fauna largely comprised of polychaetes and clams has 

also been found along this northern shore (NOAA 1977). Offshore, the benthic invertebrate 

community in Kachemak Bay was dominated by hermit crabs, pandalid shrimp, and Tanner, 

Dungeness, and king crabs (NOAA 1977). Halibut, rock sole, yellowfin sole, and weathervane 

scallops were abundant in outer Kachemak Bay (NOAA 1977). 

Belugas have been observed around Kalgin Island in both summer and winter (Hansen and 

Hubbard 1999; Hobbs et al. 2005), although the summer occurrence around Kalgin Island 

appears to have diminished with the concurrent summer range contraction of the population 

(NMFS 2008a). The Upper Subdistrict, located east of Kalgin Island to the Kenai Peninsula, can 

account for 60% or more of the commercial salmon harvests from upper Cook Inlet (Shields and 

Dupuis 2012). This area may be very productive due to current convergence/divergence and 

associated upwelling with shrimp, crabs, and clams found offshore (NOAA 1977).

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

1981198319851987198919911993199519971999200120032005200720092011

Total Biomass

(short tons)

Year
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-45

Belugas have also been observed in the Kenai River Estuary, likely feeding on eulachon or 

adult salmon. In 2003, 31 taxonomic groups of fishes and macroinvertebrates were found in this 

area (Willette et al. 2004). In April, epibenthic invertebrates (Crangon spp., Neomysis spp., and 

Saduria spp.) were most abundant, and finfish (mostly longfin smelt) were present, but rare. In 

June, finfish (mostly eulachon, juvenile sockeye, coho, and Chinook salmon, Pacific staghorn 

sculpin, snake prickleback, and starry flounder) were most abundant. In September, eulachon, 

juvenile coho salmon, Pacific herring, Pacific sandfish, and starry flounder were most abundant.

In deep mid-channel habitats, spiny dogfish and starry flounder were most abundant. Thus, there 

appears to be high species diversity with species abundance dependent on season and habitat.

Belugas have frequented Knik Arm where they likely feed on migrating adult salmon 

(Huntington 2000, NMFS 2008a). However, Pacific staghorn sculpin also occur in Knik Arm at 

low densities, primarily nearshore from July to November and offshore from April to July 

(KABATA 2006). Walleye pollock also occur in Knik Arm at low densities in nearshore habitats 

from April to July. Eulachon, mostly post-spawning fish, were found primarily in nearshore 

habitats from May to July (KABATA 2006). Pentec Environmental (2005) identified 19 fish 

species in Knik Arm, and Morsell et al. (1983) identified 18 fish species in upper Knik Arm. All 

five species of juvenile salmon use Knik Arm as a migratory corridor. Chinook and coho salmon 

enter the Arm at a larger body size, reside in nearshore habitats, and remain in the Arm during 

May to November. Chum, sockeye, and pink salmon juveniles enter the arm at a smaller body 

size and reside in more offshore habitats for May to August. In recent years, belugas have also 

been found along the northern shore of Cook Inlet between Tyonek and the Little Susitna River, 

likely feeding on migrating eulachon and adult salmon. While surveys for juvenile fish identified 

19 species in this area, herring and pink salmon were the most abundant (Moulton 1997).

2. Fisheries Management

For commercially fished species, the availability of potential beluga prey in upper Cook Inlet 

during spring and summer can be somewhat inferred from the timing and location of fishery 

harvests and upriver spawning migrations (also referred to here as “escapements”). However, 

actual quantitative data on the spatial and temporal distribution of these beluga prey in upper 

Cook Inlet are limited. For example, long-term salmon escapement estimates are available for 

the three large middle Inlet rivers, the Kenai, Kasilof, and Crescent river systems, and for the 

Yentna River, a tributary of the Susitna River, with less frequent estimates available for some 

other Cook Inlet tributaries (Westerman and Willette 2011). Because sockeye salmon returns to 

the Kenai and Kasilof rivers comprise the largest component of upper Cook Inlet salmon returns, 

the bulk of fishing pressure by humans occurs south of these two river systems and, thus, 

“downstream” of the current primary beluga summer habitat. While more salmon are available in 

the central Cook Inlet areas, few belugas venture into the central Cook Inlet area in most years. 

Belugas in northern Cook Inlet likely benefit from the tendency of anadromous prey species to 

be concentrated by shallow water and the time required to transition from salt water to fresh as 

they enter the stream mouths, which presumably makes these prey easier to capture.

Management of anadromous fish populations in Alaska attempts to constrain harvests to be 

no greater than the level of surplus production, defined as returning adult salmon in excess of the 

spawning production needed to maintain productive salmon populations (Quinn and Deriso 

1990). In addition to reproductive needs, harvest considerations must include upstream 

consumptive uses such as recreational and subsistence fisheries (Shields 2010), as well as 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-46

allowances for natural mortality, which includes predation by beluga whales, bears, and other 

species. Stock productivity and the level of surplus production are notoriously difficult to predict 

and estimate accurately due to high annual variation in factors such as freshwater and marine 

survival. To account for this uncertainty, for targeted species, fisheries are managed with inseason reductions or closures if those fish stocks appear to be weak. However, the potential for 

overfishing exists annually, and it is unlikely that escapement goals will be met in all tributaries 

across all years. While corrective management measures are typically implemented in any year 

following an under-escapement, prediction of future fish returns and managing for optimal 

harvest of those returns remains uncertain. Thus, while fishery management, on average, should 

provide sufficient total numbers of prey for belugas, the timing of prey concentration or densities 

in the river mouths may not be adequate for efficient feeding by belugas. In addition, a fishery 

would not be reduced or closed if escapement goals are met. But if the escapement goal arrived 

in a shorter time period (e.g., 30 days instead of 90 days), the benefit of optimal returns to CI 

beluga energetics may be very different.

A contrasting management situation for beluga prey exists with eulachon, which also return 

to freshwater to spawn. Although eulachon spawning stocks can be found in numerous central 

Cook Inlet rivers, human fishing effort occurs primarily in tributaries in Knik and Turnagain 

arms. Because fishing tends to occur near the river mouths or upriver, this fishing effort often 

occurs “upstream” of beluga foraging, such that population level effects of overfishing would be 

reflected by poor spawning escapement and reduced prey availability in subsequent years. 

Eulachon populations are not assessed or monitored, but ADF&G uses the Statewide Harvest 

Survey to derive recreational harvest estimates post-season. These estimates are presumed to be 

somewhat related to eulachon population abundance. If a decline in annual harvests occurs and is 

suspected of indicating a substantive decline in eulachon abundance, ADF&G may implement 

more restrictive fishing measures in subsequent years. There had been a sporadic commercial 

fishery for eulachon since 1978 (taking from 300–100,000 pounds in 1978, 1980, 1998 and 

1999; Shields 2005). Based on a concern that a reduction in the availability of eulachon could be 

detrimental to belugas, NMFS recommended to the Alaska Board of Fisheries that this fishery be 

discontinued effective beginning in 2000, in part due to the lack of data on the eulachon runs into 

the Susitna River, and due to the absence of any evaluation of the effect of this fishery on

belugas in terms of disturbance/harassment or competition for these fish. Additionally, it was 

noted: belugas may be heavily dependent on the oil-rich eulachon early in the spring (preceding 

salmon migrations), the runs are very short in duration, and large eulachon runs may occur in 

only a few upper Inlet streams. The commercial fishery for eulachon was closed in 2000, but 

reopened in 2005, under restrictions to hand-operated dip nets in saltwater between the Chuitna 

River and the Little Susitna River, with a total harvest of 100 tons or less (Shields 2005, Shields 

and Dupuis 2012; Shields and Dupuis 2016; P. Shields, ADF&G, pers. comm.).

Beluga prey resources, such as salmon and eulachon, typically represent a mixture of 

spawning stocks that are also harvested in mixed-stock fisheries (Shields 2010; Westerman and 

Willette 2011; Shields and Dupuis 2016). Effects of overfishing by humans on beluga foraging 

success are not well known, yet likely include spatial and temporal components for any specific 

prey resource that is overfished. Stock composition is dynamic and varies annually in both the 

run strength and run timing of individual contributing stocks. For major stocks or indicator 

stocks, harvest managers have tried to determine the relationship between annual escapements 

and returns in subsequent years. These relationships often have an optimal range such that 

escapement larger or smaller than this range are presumed to generate reduced adult salmon 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-47

returns in future years. Harvest managers attempt to regulate fishing effort, typically in mixedstock fisheries, to ensure that spawning escapement goals are achieved for each monitored 

salmon stock. However, it is not always possible to ensure that all target stocks are under fished, 

without exceeding the upper bound (over fishing) on some stocks.

3. Competition for CI Beluga Prey Resources

Over time, selective fishing pressure, or other factors, can alter reproductive migration timing 

of some prey species. For instance, intensive fishing during the early part of a salmon run can 

reduce the portion of the stock that returns early in the run and slightly shift future run timing, 

but the extent of that shift is limited as survival decreases outside of an optimal migration timing 

(Smoker et al. 1998). Thus, the timing of prey concentration or densities in the river mouths may 

not be adequate for efficient feeding by belugas. Chronic and persistent overharvesting of one or 

more unique salmon stocks or stocks from a specific spatial and/or temporal component (e.g., 

repeated overharvesting of upper Cook Inlet, early season runs) also has the potential to 

restructure the ecosystem. Such a pattern could cause a shift in beluga foraging toward lessnutritious prey items or a geographic displacement from the optimal foraging habitat, ultimately 

with reduced survival and reproductive success. However, the time frame over which such shifts 

could occur is unknown, and no baseline data currently exist to detect such shifts. 

Although there is no definitive analysis of competition between CI belugas and other marine 

mammals that consume the same prey, the possibility of competitive overlap in prey exists. For 

example, Chinook and coho salmon were found to be prey items for CI belugas (Quakenbush et 

al. 2015), so that any predator (including humans) that takes these species from stocks used by 

belugas are potential competitors. Resident (fish-eating) killer whales along the north Gulf Coast 

of Alaska are known to focus on salmonids, particularly Chinook, chum, and coho salmon 

(Matkin et al. 2010). These fish-eating resident killer whales are common in lower Cook Inlet 

and may intercept salmon destined for rivers and streams in the upper Inlet that are potential 

beluga prey; however, resident killer whales are not known to range into the upper Inlet where 

they might compete directly with CI belugas for prey. Harbor seals and Steller sea lions are also 

known salmonid predators that occur within the range of CI belugas and could compete with 

belugas and each other for these prey. Harbor seals, Steller sea lions, killer whales, humpback 

whales, gray whales, minke whales, harbor porpoises, sea birds, sea otters, and humans may also 

have competition effects on belugas through their consumption of eulachon.

The estimated annual rate of increase in sea otters in Kachemak Bay between 2002 and 2008 

was 26% per year, exceeding the estimated maximum productivity rate for this species and is 

presumably due in part to immigration from other areas (Gill et al. 2008). Sea otters have been 

found as far north as Ninilchik (V. Gill, USFWS, pers. comm.). Systematic surveys have not 

been done for several years and trends are unknown for Cook Inlet/Shelikof stocks of harbor 

seals, the Gulf of Alaska stock of harbor porpoise, the Alaska stock of Dall’s porpoise, or the 

Alaska stock of minke whales (Allen and Angliss 2012). The Eastern North Pacific gray whale 

stock and both the Western and Central North Pacific stocks of humpback whales have been 

increasing based on recent abundance estimates (Allen and Angliss 2012). None of these 

potential competitive effects have been quantified.

Resident killer whales likely do not directly compete for prey resources within the range of 

CI belugas, given limited to no overlap in their distribution with CI belugas (Lammers et al. 

2013). Similarly, sea otters and Steller sea lions are likely not effective competitors with CI 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-48

belugas, as they overlap with belugas in only a small portion of their range in lower Cook Inlet. 

While likely not in direct competition for adult salmon, the introduction of northern pike, an 

invasive species found in freshwaters of northern Cook Inlet, has likely reduced local salmon

stocks, particularly Chinook, through predation on juveniles (Oslund and Ivey 2010). 

4. Ecosystem Shifts and CI Beluga Prey

Both the relative and total abundances of any beluga prey item are not constant and can be 

expected to change over both space and time. Productivity of many marine species, including, 

but not limited to, potential beluga prey, may have responded to decadal-scale climate shifts in 

the North Pacific (Hollowed and Wooster 1992; Beamish and Bouillon 1993; Hare and Mantua 

2000). Recognized climate regime shifts that occurred around 1976 and 1989 (Anderson and 

Piatt 1999; Zheng and Kruse 2000; Hare and Mantua 2000; Kruse 2007; Mueter et al. 2007) may 

have affected the productivity of marine species in the North Pacific, although response to 

ecological changes can vary temporally by species, with some responding sooner than others, or 

in different trends, or greater magnitudes (Rodinov and Overland 2005). For example, the 

northern Gulf of Alaska changed from an ecosystem dominated largely by invertebrate (crabs 

and shrimps) biomass in the 1960s to 1970s to dominance by gadids and flatfishes. Robards et al. 

(1999) found a 1,000-fold increase in gadid abundance in lower Cook Inlet between the 1970s 

and 1990s, and a lesser increase in abundances of pleuronectids and salmonids. Small-mesh 

trawl surveys in Kachemak Bay documented a decline in pandalid shrimps and an increase in 

demersal fishes since the 1970s (Figure F11). Walleye pollock, flathead sole, and starry flounder 

became the dominant demersal fishes, comprising over 40% of the survey catch in 2004 to 2006 

(Goldman et al. 2007). A similar change was observed in small-mesh surveys from Kodiak 

Island to Pavlof Bay (Anderson and Piatt 1999), with ongoing surveys indicating continued low 

levels of stock biomass for many potential forage species including shrimp, juvenile pollock, and 

herring (Figure F12; D. Urban, NMFS, pers. comm.). Eulachon exhibited a resurgence in the 

2000s, but declined in 2010, coincident with an increase in commercial harvest. The climate 

regime shift in the North Pacific during the late 1970s was associated with aspects such as 

increased ocean temperatures and increased abundances of predatory fishes, such as Pacific cod. 

A study of the decline in the Kachemak Bay stock of northern shrimp found that a strong 

increasing trend in natural mortality followed the 1976 to 1977 regime shift, paralleling trends in 

increased Pacific cod abundance (Fu and Quinn 2000; Fu et al. 2000). A study of red king crab 

around Kodiak Island attributed the initial population crash to overfishing, but suggested that,

despite a fishery closure since 1983, the stock has failed to recover due to increased juvenile 

mortality associated with higher ocean temperatures and greater abundance of predatory fishes, 

such as Pacific cod (Bechtol and Kruse 2010). Pacific cod and walleye pollock, while not 

historically “rare” in Cook Inlet, occurred at much lower levels of biomass and abundance prior 

to the late 1980s, when recent commercial fisheries developed (Bechtol 1995). Surveys show 

biomass of Pacific cod and walleye pollock remained relatively high through the 1990s (Figure 

F13; R. Gustafson, ADF&G, pers. comm.). Meanwhile, Tanner crab data from lower Cook Inlet 

indicate dramatic declines in abundance of harvestable crabs after the mid-1970s (Figure F14; 

Bechtol et al. 2002; R. Gustafson, ADF&G, pers. comm.); these crabs are seasonally important 

to belugas in upper Cook Inlet.

While ecosystem response to environmental forcing is likely nonlinear (Hare and Mantua 

2000), evidence exists for climate-driven changes in the physical environment affecting other 

fish populations in the Gulf of Alaska and eastern Bering Sea. For example, strong pollock 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-49

recruitment in the eastern Bering Sea appears connected to above normal air and bottom 

temperatures and reduced sea ice cover, factors that promote zooplankton production (Quinn and 

Niebauer 1995). Solid sea ice is not a factor in the northern Gulf of Alaska, but the pre-1976 

regime was associated with low sea surface temperature and low biomasses of predatory fishes, 

such as flatfishes and Pacific cod. During and following the 1976 regime shift, high sea surface

temperatures enhanced zooplankton production in the Gulf of Alaska, supporting strong pollock 

recruitment amid low demersal fish predation (Bailey 2000; Ciannelli et al. 2005). However, 

high zooplankton populations may have been detrimental to phytoplankton needed for firstfeeding larvae of many species. Sea surface temperatures declined somewhat following the 

regime shift, but ecosystem “maturation” in the subsequent decade resulted in increased biomass 

of predatory fishes, particularly Pacific halibut, arrowtooth flounder, flathead sole, and Pacific 

cod (Bailey 2000). The North Pacific ecosystem has been generally characterized by moderate 

sea surface temperature in recent decades, but relatively high demersal fish biomass (Hare and 

Mantua 2000; Mueter and Norcross 2002; Ciannelli et al. 2005). As a result, a compromised 

feeding environment for many larval forage species was coupled with intensified groundfish 

predation.

A cautionary note is warranted regarding interpretation of the role of long-term 

environmental effects as drivers of potential ecological change. Ecological systems are complex,

and trends in abundance and biomass are typically the result of a variety of factors. A first step in 

understanding ecosystem change is to have a sufficiently long time series of indices for both 

potential ecosystem drivers and the species of interest. Unfortunately, these indices are often 

discontinuous over time or of an inappropriate spatial coverage. Surveys of potential CI beluga 

prey in marine or estuarine areas of upper Cook Inlet have been infrequent and short-term, 

typically implemented to address ad hoc environmental assessment needs for resource 

development. Use of commercial harvests to represent potential CI beluga prey is likely biased 

because harvests typically occur “downstream” of feeding CI beluga. Use of salmon 

escapements to represent CI beluga prey is also biased because escapements occur “upstream” of 

CI beluga foraging areas. In addition, many escapement indices are discontinuous over time as 

monitoring techniques or tributaries change in response to management priorities and agency 

budget limitations. The small-mesh trawl survey in Kachemak Bay dates to 1977 and provides a 

basis for long-term ecosystem changes, but was reduced in frequency and then discontinued after 

2006 due to financial priorities. A multi-species trawl survey, focused on Tanner crab, but also 

providing population estimates of species like Pacific cod, walleye pollock, and arrowtooth 

flounder in lower Cook Inlet, dates to 1990 but has also been reduced in frequency due to budget 

priorities.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-50

Source: Gustafson and Bechtol 2005; Goldman et al. 2007; R. Gustafson, ADF&G, pers. comm.

Figure F11. Historical biomass (millions of pounds) of pandalid shrimps, demersal fishes, and other 

invertebrates from small-mesh trawl surveys in Kachemak Bay.

Source: D. Urban, NMFS, pers. comm.

Figure F12. Anomalies in the mean catch of dominant forage species in the Kodiak small-mesh trawl surveys, 

1975 to 2010.

0

2

4

6

8

10

12

14

16

18

20

197719791981198319851987198919911993199519971999200120032005

Biomass

(million lb)

Fish and non-pandalid 

invertebrates

Pandalid shrimp

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

5.0

1975 1980 1985 1990 1995 2000 2005 2010

anomaly from mean

Pandalid shrimp

Eulachon

Juvenile pollock

Herring
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-51

Source: R. Gustafson, ADF&G, pers. comm.

Figure F13. Bottom trawl survey biomass estimates of Pacific cod and walleye pollock in Kachemak Bay and 

Kamishak Bay, lower Cook Inlet, 1989 to 2009.

0 

5 

10 

15 

20 

25 

30 

35 

19891991199319951997199920012003

20052007

2009

Biomass (million lb)

Year

Kachemak Bay Pacific cod

Kachemak Bay Pollock

Kamishak Bay Pacific cod

Kamishak Bay Pollock
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan F – CI Beluga Prey Supplement

IX-52

Source: Bechtol et al. 2002; R. Gustafson, ADF&G, pers. comm.

Figure F14. Pot and trawl survey estimates, and subsequent harvests, for legal (i.e., legal size to harvest) male 

Tanner crabs in the Kamishak and Barren Islands Districts (top panel) and the Southern District (Kachemak 

Bay, lower panel), 1968 to 2012.

0

5

10

15

20

25

30

35

40

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1968-69 1971-72 1974-75 

1977-78 1980-81 1983-84 

198619891992199519982001200420072010

Pot Survey (crabs/pot)

Million Crab

Season

Kachemak Bay

Harvest

Trawl Survey

Pot Survey

0

5

10

15

20

25

30

35

40

0.0

0.4

0.8

1.2

1.6

2.0

2.4

1968-69 1971-72 1974-75 

1977-78 1980-81 1983-84 

1986198919921995199820012004

20072010

Pot Survey (crabs/pot)

Million Crab

Season

Kamishak Bay

Harvest

Trawl Survey

Pot Survey
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-53

G. CI Beluga Pollution and Contaminants Supplement

NOTE TO READER: The text below was developed by the CIBRT and reproduces information 

readily available in other reports. In Section III.A.9 of this document, we provided information 

sufficient to justify recovery criteria and actions addressing pollution. Additional information 

about pollution and contaminants reviewed for Cook Inlet and CI belugas follows.

Pollution is the introduction of contaminants into the environment that causes adverse 

change. For the purpose of this review, pollution is synonymous with acute or chronic events that 

release notable/reportable quantities of chemicals or substances into the environment. Exposure 

to industrial chemicals as well as to natural substances released into the marine environment is a 

potential health threat for CI belugas and their prey.

Available literature was reviewed by NMFS for the Cook Inlet Beluga Whale Conservation 

Plan (NMFS 2008a) and by URS Corporation (2010). The reviewed publications vary in their 

use of terminology regarding lipid, blubber, dry weight, and wet weight. In particular, some 

authors consider blubber and lipid to be synonymous and interchangeable terms, whereas others 

consider blubber to be a combination of lipids and water. Therefore, it is important to ensure that 

comparisons of tissue concentrations and threshold levels are based on consistent assumptions of 

measurement media and units. 

There is little information on the potentially deleterious effects of chemicals on CI belugas. 

Potential sources of anthropogenic contaminants include wastewater treatment, freshwater 

runoff, airport de-icing chemicals, ballast water discharges, gas and oil releases or spills, military 

training areas, and other industrial development and activities. While NMFS has some data about 

levels of traditionally studied contaminants in CI belugas (e.g., Dichlorodiphenyltrichloroethane 

[DDT], polychlorinated biphenyls [PCBs], polycyclic aromatic hydrocarbons [PAHs], etc.), 

virtually nothing is known about other emerging pollutants of concern and their effects on CI 

belugas. The emerging pollutants of concern include endocrine disruptors (substances that 

interfere with the functions of hormones), pharmaceuticals, personal care products, and prions 

(proteins that may cause a disease), amongst other bacterial and viral agents that are found in 

wastewater and biosolids. 

URS (2010) evaluated the level of concern for various classes of chemicals that were of 

probable, possible, or unlikely concern. Chemicals of concern for which data are available are 

described in Table 8, and representative values from various beluga populations and marine 

mammals in Cook Inlet are listed in Table G1. Table G2 lists those chemicals of possible 

concern for which there are no data available for any beluga population. Chemicals considered 

by URS (2010) to be unlikely of concern for CI belugas include: hydrocarbons (other than PAH 

compounds), glycols, diagnostic agents, dietary supplements, personal care products, engineered 

particles (<100 nanometers), or prions. Figure G1 summarizes data for known concentrations of 

various contaminants found in the blubber of male belugas from North America.

1. Organochlorines

PCBs were used in hundreds of industrial and commercial applications including electrical, 

heat transfer, and hydraulic equipment; as plasticizers in paints, plastics, and rubber products; in 

pigments, dyes, and carbonless copy paper; and many other industrial applications. Though their
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-54

Table G1. Tissue concentrations of analyzed substances for belugas from Cook Inlet and other regions.

Group Groupa

Male Female

Tissue

Mean or median 

concentration 

± 1SD (range)

Mean or median 

concentration 

± 1SD (Range)

Organochlorides (mg/kg wet)

Total PCBs CI (1992–97) b 1.49 ± 0.70 0.79 ± 0.56 blubber

Pt Lay (1990, 1996) b 5.20 ± 0.90 1.50 ± 1.12 blubber

SLE (1986–87) b 75.8 ± 15.3 37.3 ± 22.0 blubber

Total DDTs CI b 1.35 ± 0.73 0.59 ± 0.45 blubber

Pt Lay b 3.63 ± 0.90 0.93 ±0.85 blubber

SLE b 101 ± 32.6 23.0 ± 17.3 blubber

Toxaphene CI b 2.40 ± 1.06 2.02 ± 0.46 blubber

Pt Lay b 3.93 ± 1.16 2.62 ± 2.07 blubber

SLE b 14.7 ± 2.46 6.34 ± 3.51 blubber

Chlordane compounds CI b 0.56 ± 0.25 0.30 ± 0.22 blubber

Pt Lay b 2.42 ± 0.46 0.79 ± 0.61 blubber

SLE b 7.43 ± 0.63 3.55 ± 1.99 blubber

Dieldrin CI b 0.09 ± 0.05 0.06 ± 0.05 blubber

Pt Lay b 0.39 ± 0.09 0.12 ± 0.10 blubber

SLE b 0.93 ± 0.12 0.56 ± 0.31 blubber

Hexachlorobenzene (HCB) CI b 0.22 ± 0.09 0.15 ± 0.13 blubber

Pt Lay b 0.81 ± 0.12 0.23 ± 0.28 blubber

SLE b 1.34 ± 0.44 0.60 ± 0.43 blubber

Hexachlorocyclohexane 

(Sum HCH)

CI b 0.21 ± 0.07 0.17 ± 0.05 blubber

Pt Lay b 0.33 ± 0.76 0.25 ± 0.12 blubber

SLE b 0.37 ± 0.11 0.24 ± 0.10 blubber

Mirex CI b 0.01 ± 0.01 0.01 ± 0.00 blubber

Pt Lay b 0.06 ± 0.02 0.02 ± 0.01 blubber

SLE b 1.00 ± 0.64 1.11 ± 0.99 blubber

Perfluorinated compounds

Perfluorooctane sulfonate

ng/g ww (PFOS)

CI 1992 to 2006 c 22.5 (14.4–30.4) 13.0 (4.61–70.3) liver

E. Chukchi 1989 to 2000 c 9.2 (4.29–28.4) 4.76 (1.81–38.1) liver

Perfluorooctane 

sulfonamide (PFOSA)

CI 1992 to 2006 c 11.4 (4.52–17.9) 18.4 (10.4–27.8) liver

E. Chukchi 1989 to 2000 c 31.8 (17.7–63.8) 27.8 (11.2–65.7) liver

Perfluorononanoic acid

(PFNA)

CI 1992 to 2006 c 1.79 (0.454–3.08) 1.66 (<0.502–5.67) liver

E. Chukchi 1989 to 2000c 0.670 (0.170–2.55) 0.960 (<0.180–5.46) liver

Polycyclic aromatic hydrocarbons (PAHs) μg/g lw

Total PAHs CI d 2.6 ± 3.8 1.2 ± 1.9 liver

CI d 6.9 ± 7.4 27.8 ± 29.4 blubber
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-55

Group Groupa

Male Female

Tissue

Mean or median 

concentration 

± 1SD (range)

Mean or median 

concentration 

± 1SD (Range)

Polybrominated diphenyl ethers (PBDEs) (ng/g lipid)

CI 1989 to 2006 e 13.8 (6.56–45.6) 14.6 (7.40–32.0) blubber

E. Chukchi 1989 to 2000e 12.8 (4.33–32.2) 5.05 (1.90–19.4) blubber

SLE 1988 to 1999 f 430 (170–780) 540 (300–1060) blubber

SLE 2000 to 2003g 2,210 (246–3030) liver

Metals/Inorganics (mg/kg dry)

Cadmium (Cd) CI b 2.39 liver

Pt Lay b 9.38 ± 3.39 liver

SLE b 0.53 ± 0.41 liver

Mercury (Hg) CI b 16.3 ± 13.0 liver

Pt Lay b 179 ± 78.6 liver

SLE b 126 ± 161 liver

Copper (Cu) CI b 162 ± 130 liver

Pt Lay b 61.6 ± 42.3 liver

SLE b 0.58 ± 0.41 liver

Mercury (Hg) CI b 16.3 ± 13.0 liver

Pt Lay b 179 ± 78.6 liver

SLE b 126 ± 161 liver

Selenium (Se) CI b 14.3 ± 7.0 liver

Pt Lay b 97.2 ± 76.7 liver

SLE b 79.2 ± 110 liver

a CI - Cook Inlet belugas, Pt. Lay - Point Lay belugas, SLE - St. Lawrence Estuary belugas.

Sources: b. Becker et al. 2000 (males, n = 10; females, n = 10); c. Reiner et al. 2011 (CI, PFOS and PFOSA: males, n =11, females, n = 16; CI, 

PFNA: males, n = 11, females, n = 15; E. Chukchi PFOS and PFOSA: males, n = 25, females, n = 16; E. Chukchi, PFNA: males, n = 25, females, 

n = 13); d. Wetzel et al. 2010; e. Hoguet et al. 2013 (CI: males, n = 15, females, n = 12; E. Chukchi: males, n = 25, females, n = 15); f. Lebeuf et 

al. 2004 (males, n = 15; females, n = 14); g. McKinney et al. 2006 (males, n = 3, females, n = 3).

production has been banned in North America since 1979, PCBs still pose a risk to humans and 

wildlife because they are highly toxic and persist in the environment. These and other 

organochlorines such as DDT have high-fat, low-air, and poor-water solubility, allowing them to 

accumulate in fatty tissues. Being highly persistent in the environment, these compounds 

bioaccumulate through trophic transfer, resulting in higher concentrations in upper level

predators such as marine mammals. High concentrations in animals are associated with poor

health and reproduction. Concentrations of various organochlorines in CI belugas were 

consistently lower than levels observed in belugas from Point Lay and one to two orders of 

magnitude lower than levels seen in SLE belugas (Becker et al. 2000). The PCB values for CI 

belugas were at levels associated with endocrine disruption, lower than established thresholds for 

immunosuppression, but close to levels that disrupted immune function in free ranging harbor 

seals (as low as 2.5 milligrams [mg] per kilogram [kg] of PCBs; Levin et al. 2005, Shaw 2005). 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

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Table G2. A brief description of compounds of possible concern to CI belugas, but for which no data are 

available for Cook Inlet or other beluga populations.

Class Of Substance Specific Examples

Organophosphatesa/carbamates Commonly used as broad-spectrum insecticides: Malathiona

, methylparathion, chlorpyrifos, diazinon, carbaryl, aldicarb

Phthalates Commonly used in vinyl softeners in flooring and in adhesives, plastic 

clothing, toys, and kitchen ware: Diethyl phthalate, butyl benzyl phthalate

Prescription and over the counter drugs Commonly used medicinally for humans and animals: Penicillins, 

tetracyclines, clofibric acid, aspirin, ibuprofen, prozac, agricultural animal 

growth promoters, aminoglycosidesa

, aspirina, furosemidea

Alkylphenols Commonly used in detergents and cleaning agents: Nonylphenol, 

octylphenol

Consumer plastics Commonly used in CDs, DVDs, eyeglasses lenses, and bottles: Bisphenol 

A (BPA) (2,2-bis(4-hydroxydiphenyl) propane)

Natural and synthetic hormones Commonly used medicinally for humans and animals: Estradiols, 

thyroxine analogs

Surfactants Commonly used in detergents, cosmetics, and spermicides: 4-

nonylphenol; "alkylphenol polyethoxylate surfactants"; o-, m-, or pnonylphenol

Pesticides/Herbicides Commonly used to control “pests” including insects, fungi, plants, 

rodents, birds, spiders, mites: Lindane, methyl-parathion; permethrin; 

triazines, bifenthrin, cypermethrin, esfenvalerate; pyrethroidsa

, paraquata

a Denotes compounds with known ototoxic effects.

Source: URS 2010.

In a study of California sea lions, LeBoeuf et al. (2003) did not find any evidence that 

population growth or the health of individual sea lions had been compromised at mean total PCB 

concentrations of 12 mg/kg blubber weight and mean total DDTs concentrations of 37–41 mg/kg 

blubber wet weight, which are substantially higher than levels seen in CI belugas. Bristol Bay 

and CI beluga populations appear to carry very similar body burdens of most persistent organic 

pollutant contaminants, although CI belugas may be exposed to a larger amount of PCBs of 

aroclor origin (Northwest Fisheries Science Center, NMFS, unpub. data). Additionally, 

contaminant signatures were consistent with Bristol Bay belugas consuming prey originating

from Asia and the Arctic, whereas the signatures in CI belugas did not exhibit indications of 

consumption of prey originating from outside Cook Inlet and the Gulf of Alaska (Herman et al., 

NMFS, unpub. data). 

In a study of PCBs and organochlorine pesticides from blubber biopsies of free-ranging SLE 

belugas, concentrations had overlapping but lower ranges when compared to samples obtained 

from dead stranded belugas from Cook Inlet (Hobbs et al. 2003). The authors suggest that the 

differences observed are due to different feeding habits, particularly with regard to eels, and that 

elevated organochlorines were having an effect on the health of the SLE whales to an extent that 

led to higher mortality. Additionally, the authors caution that relying only on samples from 

stranded whales could bias study results because contaminant concentrations are likely elevated 

in stranded whales relative to what occurs in the population as a whole. Interestingly, this study 

also compared values to those obtained from SLE harbor seals, noting that most major 

compounds in the biopsied belugas occurred at similar levels in the seals, and followed similar 

age and sex-related trends (Bernt et al. 1999). This suggests sampling Cook Inlet harbor seals 

may be a viable surrogate species for investigating contaminant loads in CI belugas.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-57

Notes: When available, geographic locations, dates of sample collections, and number of animals are shown on the X axis.

Source: Becker 2000.

Figure G1 (a-f). Concentrations (mean +/- 1 standard deviation) of various contaminants in the blubber of male North American belugas.

a) PCBs, DDT, toxaphene, and chlorane b) Dieldrin, HCB, HCH, and 

mirex

c) Copper
Cook Inlet Beluga Whale IX. APPENDICES

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IX-58

Figure G1 (a–f). Continued.

d) Total Mercury e) Selenium f) Cadmium
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-59

2. Perfluorinated Compounds 

The perfluorinated compounds (PFCs), which include Teflon, are compounds commonly 

used as water and oil repellants in protective coatings in food packaging, textiles, and carpeting. 

While PFCs are not well studied in marine mammals, PFCs have recently become contaminants 

of possible concern. CI belugas had higher concentrations of most PFCs compared to beluga 

from the eastern Chukchi but a lower median concentration of one particular type of PFC, 

namely perfluorooctane sulfonamide (Reiner et al. 2011). Temporal trends indicated most PFC 

concentrations have steadily increased from 1989 to 2006, whereas a study involving sea otters 

from lower Cook Inlet has shown a general decrease since about 2001 (Hart et al. 2009). 

Previous studies examining PFCs in beluga livers from the Canadian Arctic have found 

individual PFC concentrations >150 ng/g (Kelly et al. 2009 and Tomy 2009 as cited in Reiner et 

al. 2011), notably higher than values from CI belugas. Differences suggest different sources or 

transport pathways for these compounds, which can be related to the geographic differences in 

the long-range atmospheric transport of PFCs, oceanic transport of PFCs, local releases, and/or 

feeding habits (Reiner et al. 2011).

3. Polycyclic Aromatic Hydrocarbons

This class of compounds is naturally occurring in fossil fuels and is also released from forest 

fires, industrial products (e.g., asphalt and coal tar), and the incomplete combustion of coal, oil, 

gas, or organic waste (compounds of particular concern are benzo(a)pyrene, anthracene, and 

pyrene). These are some of the most widespread organic pollutants. The PAH compounds are 

lipophilic (oil-loving), with larger compounds even less water-soluble and less volatile. Because 

of these properties, PAHs in the environment are found primarily in soil, sediment, and oily 

substances, as opposed to water or air. However, they are also a component of concern in 

particulate matter suspended in air. Representing the most toxic components of oil, and including 

16 compounds, PAHs are considered priority pollutants by the World Health Organization and 

the U.S. Environmental Protection Agency (EPA). The PAHs can enter the environment in a 

number of ways, including, but not limited to: oil and gas development activities; run-off from 

streets or parking areas; leakage from watercraft; oil spills; natural oil seeps and forest fires. One 

PAH, benzo(a)pyrene, has been identified as the most likely cause of high numbers of cancers in 

belugas from the SLE; in addition, PAHs have numerous known effects besides carcinogenesis 

in mammals, and these include effects on reproduction and survival of offspring.

A study analyzed PAH levels in belugas, prey species, and sediments from Cook Inlet. The 

highest PAH levels in the sampled sediments were found in Eagle Bay (Wetzel et al. 2010).

Although naphthalenes, anthracenes, and phenanthrenes were the most ubiquitous classes of 

PAHs found, benzo(a)pyrene was also detected in all sediment samples (Wetzel et al. 2010). The

data suggested inputs from both combustion and fresh oil. Total PAH levels were moderate, 

relative to those found in other locations known to have environmental problems with PAH

contamination (Wetzel et al. 2010). The same general patterns occurred in the salmon, eulachon

and saffron cod, but the fish contained slightly higher amounts of pyrene and fluorine 

constituents than did the sediments (Wetzel et al. 2010). The highest PAH values were in

eulachon taken from the Little Susitna River (Wetzel et al. 2010). Some Chinook salmon from 

Ship Creek contained notable levels of total PAHs in their flesh; roe from some sockeye salmon 

was also notably high in total PAHs (Wetzel et al. 2010). 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-60

As noted above, an especially strong correlation was found between high levels of PAHs and 

illness and mortality of belugas in the SLE and humans living in the vicinity (Martineau et al. 

1994, 2002), underscoring the susceptibility of both species to this class of contaminants. 

Although the correlation suggests a cause and effect relationship, none has been proven for the 

beluga. The chronic PAH contamination in SLE represents a clear threat to the health status of 

resident species; SLE belugas have shown a greater prevalence of cancer than any other group of 

cetaceans in the world (Martineau et al. 2002). One particular PAH, benzo(a)pyrene, appears to 

be the primary culprit. 

CI belugas appear to bioaccumulate PAHs from the environment, including from their prey. 

CI belugas have much higher PAH levels than do subsistence-harvested belugas from 

MacKenzie River Delta (Wetzel et al. 2010). Highest PAH levels in CI beluga livers were found 

in three adult males and a female fetus; the highest levels in blubber were from adult females and 

fetuses (Wetzel et al. 2010). The most prevalent types of PAHs found in beluga liver samples 

were fluorenes, anthracenes, and phenanthrenes (Wetzel et al. 2010). No benzo(a)pyrene was 

detected. PAH concentrations in the blubber of females were statistically higher than in males 

(Wetzel et al. 2010). The most prevalent types of PAHs found in beluga blubber were 

naphthalenes, fluorenes, anthracenes, and fluoranthracenes; small amounts of benzo(a)pyrene 

were found in some blubber samples (Wetzel et al. 2010).

4. Metals

CI belugas had lower levels of metals of concern than other beluga populations, including 

mercury, which was below the liver threshold value of concern of 60mg/kg. The one element 

that did not follow this pattern was copper; copper levels in livers of CI belugas were two to 

three times higher than in Arctic Alaska belugas and similar to Hudson Bay belugas (Becker 

2000). While copper has not been associated with toxic effects in CI belugas, these levels are 

substantially higher than the renal damage values (29 mg/kg) reported for Australian bottlenose 

dolphins (Lavery et al. 2009).

5. Emerging Chemicals

Becker (National Institute of Standards and Technology, pers. comm.) reported that CI 

belugas have significantly higher total levels of the brominated flame retardant 

Hexabromocyclododecane than the Eastern Chukchi Sea belugas from Point Lay, but 

demonstrated that levels in Alaskan belugas are lower than those measured in SLE belugas 

(Lebeuf et al. 2004) and California sea lions (Stapleton et al. 2006). However, other studies 

report that another class of flame retardants, PBDEs, are increasing over time in Chukchi Sea 

belugas and in CI Inlet belugas (Hoguet et al. 2013) as they are in SLE belugas (Lebeuf et al. 

2004).

Data for the other chemicals of possible concern (Table G2) are either not available or could 

not be evaluated at this time due to a lack of readily available threshold concentrations. 

However, toxicity reference values are available for some non-cetacean marine mammals, and 

these could be used to develop body burden-based screening levels for belugas. 

In general, for the contaminants that have been studied, CI belugas appear to have lower 

levels of contaminants stored in their bodies than do other populations of belugas. Additionally, 

chemical analyses of water and dredging sediments from Cook Inlet found that contaminants 

analyzed were below management levels, and some were below detection limits (Frenzel 2002; 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan G – CI Beluga Pollution and Contaminants Supplement

IX-61

U.S. Army Corps of Engineers [Corps] 2003). However, new chemicals of concern are 

developed or recognized on a regular basis. One study of organohalogen contaminants in 

Canadian beluga whale liver contained previously unidentified compounds and metabolites 

which may be impacting the health of Canadian beluga whale populations (McKinney et al. 

2006).

6. Ototoxic Compounds

Ototoxins are substances that temporarily or permanently damage hearing. These compounds 

include several chemicals already discussed (Table 8 and G2) and come from several classes of 

chemicals including: organic solvents (carbon disulphide, heptane, hexane, perchloroethylene, 

Stoddard solvent, trichloroethylene); pesticides; alcohols (butanol, ethanol); heavy metals 

(arsenic, lead, manganese, mercury, organic tin); drugs (aminoglycosides, aspirin, furosemide); 

PAHs (toluene, benzene, styrene, xylene); and other miscellaneous compounds (acrylonitrile, 

carbon monoxide, cyanide, organophosphates, paraquat) (Morata and Little 2002, Teixeira et al. 

2002, Steyger 2009). Organic solvents include alcohols, paints, adhesives, and fuels, including 

jet fuel (both commercial and military grade), which contain a variety of ototoxic aromatic 

hydrocarbons including toluene, styrene, ethyl benzene, and xylene (Steyger 2009). These 

chemicals can be absorbed through the respiratory tract, the skin, or the gastrointestinal tract. 

Our understanding of the effects of these compounds on the hearing of marine mammals is 

limited; however, hearing deficits have been established in cetaceans, including belugas, which 

were treated with aminoglycosides, a class of antibiotics known to be ototoxic (Finneran et al. 

2005). When exposure to ototoxic chemicals is combined with exposure to noise, hearing loss is 

exacerbated by increasing both the breadth and severity of permanent threshold shifts; hearing 

loss can even occur at subtoxic chemical and sub-traumatic noise levels, which would cause little 

or no hearing loss in the absence of the other agent (Steyger 2009). The synergistic effect of 

noise and organic solvents is more serious after repeated exposure at lower levels (Steyger 

2009).
Cook Inlet Beluga Whale IX. APPENDICES

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Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan H – Summary of a Cause of Death Analysis

IX-63

H. Summary of a Cause of Death Analysis of 34 Necropsied CI Belugas

NOTE TO READER: The text below was developed by the Cook Inlet Beluga Whale Recovery 

Team and is a detailed description of an analysis of necropsies of 34 CI belugas conducted by 

Burek-Huntington et al. (2013) from 1998–2009. In Section II.D.3 of this document, we provided

information on causes of death in necropsied CI belugas sufficient to justify recovery criteria 

and actions, including new information for necropsies of four CI belugas conducted from 2010–

2013 (for those four belugas, trauma was determined to be the cause of death; for additional 

details, see Huntington-Burek et al. 2015). Additional information about the necropsy results 

from 1998–2009 follows.

From 1998 to 2009, only 34 carcasses out of 136 observed dead stranded belugas (Table H1)

were subjected to some degree of post-mortem examination or necropsy. These carcasses were 

concentrated close to Anchorage and along the road system (Figure H1). In the 34 CI beluga 

carcasses examined between 1998 to 2009, the cause of death was not identified in a third of the 

cases examined, primarily because the vast majority were in an advanced state of decomposition 

(Burek-Huntington et al. 2013). Categories of identified causes of death in CI belugas are 

discussed below. 

1. Perinatal/Neonatal Mortality

Perinatal mortalities included deaths of four fetuses and one neonatal beluga calf in Cook 

Inlet (Burek-Huntington et al. 2013). All four fetuses were in an advanced state of decomposition 

and a clear cause for the abortion or stranding was not found. It is noteworthy that all four 

fetuses were recovered in 2008, which may suggest a common cause, but the sample size and 

insufficient common findings from postmortem exams and testing makes it impossible to support 

such a conclusion. Neonatal mortalities and dystocia (complications during birth) have also been 

observed in aquariums and in animals from the SLE (Table H2). In the wild, carcasses of young 

animals would be harder to find due to their small size and tendency to sink, so perinatal 

mortalities are undoubtedly underreported. Olesiuk et al. (1990) inferred that mortality during the 

first few months of life of killer whales in British Columbia could be as high as 37–50%. 

Hammill (2007) reported a fairly low rate of neonatal mortalities in SLE belugas during the time 

period covered by the report; however, in 2010 to 2012 there has been a notable increase in 

perinatal morality for SLE beluga adult females and calves (P. Béland, St. Lawrence National 

Institute of Ecotoxicology, unpub. data).

2. Infectious Diseases

Nineteen of the 34 examined stranded CI belugas had at least one disease and 11 had two or 

more diseases considered contributory to death, including bacterial, viral, and parasitic diseases 

(Table H3). However, diseases are easily missed in decomposed carcasses, which describes most 

of those examined from Cook Inlet. Therefore, the reported contribution of disease to overall 

mortality rates represents a minimum (Burek-Huntington et al. 2013). A greater proportion of 

deaths due to infectious diseases was seen in SLE, 32% (S. Lair pers. comm. to C. Goertz), and 

in oceanaria, 51% (L. Dunn, pers. comm. to C. Goertz), where carcasses are more reliably 

accessed in a timely manner.

Bacteria: Bacterial infections implicated as the cause of death in examined CI belugas 

included a systemic infection, pneumonia, and lung abscess (Burek-Huntington et al. 2013). 
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan H – Summary of a Cause of Death Analysis

IX-64

Source: Burek-Huntington et al. 2013.

Figure H1. Distribution of 34 CI beluga carcasses examined (1998–2009).

Culture of specific bacteria was not possible because of advanced decomposition, but organisms 

were seen on microscopic examination of tissues. Bacterial infection was the major cause of 

mortality in captive belugas (L. Dunn, pers. comm. to C. Goertz). Pathogenic bacteria isolated 

from captive beluga include Nocardia spp. (MacNeil et al. 1978), Erysipelothrix (Calle et al. 

1993), Vibrio parahaemolyticus (Higgins 2000), Edwardsiella (Higgins 2000), and 

Mycobacterium (Bowenkamp et al. 2001). Several bacteria (Edwarsiella tarda, Aeromonas 

hydrophila, Vibrio cholera, Vibrio fluvialis, Kingella kingae, Morganella morganii,

Pleisiomonas shigelloides, Shewanella putrefaciens, and Nocardia spp.) that affected SLE 

beluga are generally found in water with high loads of organic pollutants (L. Dunn, pers. 

comm.to C. Goertz; Martineau et al. 1988; De Guise et al. 1995a; Martineau 2003). The high

bacterial load of the SLE likely contributes to these bacterial infections (St. Lawrence Centre

1996). Bacteria identified in the deaths of SLE belugas were typically opportunistic, normally 

found in the environment and/or healthy hosts, but usually only causing disease when the host’s 

immunological defenses were compromised. Any factor that results in a compromised immune

system may render SLE belugas, and presumably other belugas, more susceptible to 

opportunistic bacteria. 

Viruses: The only virus identified in CI belugas was the herpes virus, which was the cause of 

death in one case (Burek-Huntington et al. 2013). Herpes viral dermatitis was an incidental 

finding in other CI belugas examined post-mortem, and herpes-like marks have been observed in 

photographs of live CI belugas (T. McGuire, LGL, pers. comm.). This type of herpes infection is

typically localized, usually not significant to the overall health of the animal, and eventually 

becomes latent leaving a distinctive scar. However, latent infections can be reactivated by such 

factors as stress and immune-suppression and can further compromise the individual (Kennedy et
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan H – Summary of a Cause of Death Analysis

IX-65

Table H1. Synthesis of primary cause of death of animals from different beluga populations as assessed by the 

references.

Cause of death

CI beluga

(1998 to 2009, n = 34) a

(%)

St. Lawrence

Estuary beluga

(1983 to 2012, n = 222) b

(%)

North American

oceanaria beluga

(1974 to 2000, n = 45) c

(%)

Degenerative 0 4 7

Neonatal/perinatal 15 7 11

Infectious disease 

o Bacterial

o Viral

o Combined bacterial / parasitic

o Parasitic

o Fungal

o Not determined

9

0

3

6

0

0

0

32

14

0

0

18

0

0

51

31

7

0

2

7

4

Nutritional 9 — —

Neoplasia 0 15 5

Trauma 9 6 2

Post live stranding 30 — Not applicable

Miscellaneous 0 8 11

Not determined 32 28 13

Notes: Infectious disease causes are further broken down into different types of pathogens when possible. Parasitic diseases include those due to 

protozoa and to metazoan parasites. When a specific pathogen could not be isolated but the lesions were consistent with an infectious etiology, 

the cause of death was categorized as “Infectious disease-Not determined.” Miscellaneous causes of death included conditions with vague 

causation or conditions that did not fit well in the other categories including anaphylaxis and drowning in captive belugas, dystocia (abnormal 

labor or birth) in wild belugas, and fishing gear entanglement.

Sources: a Burek-Huntington et al. 2013; b S. Lair, pers. comm. to C. Goertz; c L. Dunn, pers. comm. to C. Goertz.

Table H2. Summary of causes of death, contributing factors, and incidental findings from carcasses of 34 CI 

belugas examined (1998–2009).

Diagnostic category

Cause of death

(n)

Cause of death

(%) Contributing factor Incidental

Unknown 11 32 0 0

Perinatal 5 15 0 0

Mass Stranding 5 15 0 0

Single Stranding 4 12 0 0

Trauma 3 9 1 1

Nutrition 3 9 3 0

Disease 3 9 33 31

Environmental 0 0 5 0

Total 34 100 42 32

Source: Burek-Huntington et al. 2013.
Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan H – Summary of a Cause of Death Analysis

IX-66

al. 1992). Serological testing for antibodies to viral diseases of concern is only possible with 

blood from a live or very freshly dead animal, which does not include any of the carcasses in the 

CI beluga mortality study; in addition, serological testing has not been done on samples from 

live-captured CI belugas, so it is unknown what other viruses may be active in this population. 

Viruses have been implicated in the death of three captive belugas including one with herpes 

virus-like particles identified by transmission electron microscopy (L. Dunn, pers. comm. to C. 

Goertz). A few SLE animals had microscopic lesions of non-suppurative encephalitis, most 

consistent with a viral etiology; however, a subsequent test could not identify a specific virus,

and the clinical significance of these lesions was not always clear, even if this inflammation of 

the brain was believed to have been the cause of the stranding in the most severe cases (S. Lair, 

pers. comm. to C. Goertz).

Parasites: Significant parasitic infestations were noted in the lungs and kidneys of many 

necropsied CI belugas, sometimes in both sets of organs in the same individual. Thirteen animals 

(38%) had varying degrees of lungworm infection from incidental infection to association with 

bronchopneumonia. The species of pulmonary nematodes or roundworms in CI belugas has not 

been identified; species known to affect belugas include Pharurus pallasii, Stenurus 

artomarinus, Halocercus monoceris, and Stenurus minor (Measures 2001). In some beluga 

populations, infection with pulmonary nematodes was found in otherwise healthy robust animals, 

possibly suggesting a commensal relationship (Woshner et al. 2001). However, in SLE belugas, 

lungworms were listed as a significant factor in stranding mortalities (Martineau et al. 2003), and 

pneumonia, usually of parasitic origin, was one of the most common causes of death (De Guise 

et al. 1995b).

Single kidneys from 19 of 26 CI belugas contained a nematode identified as Crassicauda 

giliakiana, which has been only rarely observed in other beluga populations (Martineau et al. 

1988, De Guise et al. 1995a, Vlasman and Campbell 2003, Burek-Huntington et al. 2013). While 

extensive damage and tissue replacement has been noted in some kidneys from CI belugas, it is 

unclear whether this change results in functional damage since up to 75% of a kidney can be 

damaged in other species before causing renal failure. However, heavy burdens could 

compromise young animals or individuals stressed by other conditions. The life cycle of C. 

giliakiana is not well understood. If an intermediate host is involved, the relatively high 

prevalence of kidney nematodes in CI belugas likely reflects a variation in their diet as compared 

to other beluga populations.

Other parasites found in CI belugas includes nematodes in the gastrointestinal tract (Anisakis

or Contracaecum sp.) and in blubber (a Crassicauda sp.) as well as protozoa in muscle 

(Sarcosystis sp.), but were considered incidental and did not contribute to death (BurekHuntington et al. 2013). One instance of a trematode infection, most likely a Campulid, was 

noted in a liver. Endoparasites found in other beluga populations include: gastrointestinal 

nematodes (Contracaecum spp., Anisakis simplex sometimes in association with ulcers, 

Leucastella arctica) (Klinkhart 1966; Department of Fisheries and Oceans [DFO] and World 

Wildlife Fund 1995); trematodes or flukes (Hadwenius seymouri); and protozoa (Toxoplasma

and Sarcocysitis spp.) (Kenyon and Kenyon 1977, Wazura et al. 1986, De Guise et al. 1993, 

Martineau et al. 1994, Mikaelian et al. 2000, Measures 2001, Woshner 2001, Houde et al. 2003). 

Trichinella spiralis, a nematode found in muscle, was reported from one beluga from the Arctic 

coast of Alaska (Brandly and Rausch 1950). Many of these parasites are transmitted primarily 
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Table H3. Types of diseases described in stranded CI belugas and their coded significance from 34 carcasses 

of CI Belugas that were examined (1998–2009) as part of mortality and morbidity study.

Type of disease Cause of death Contributing factor Incidental

Combined bacterial / parasitic infections 2

Herpesviral infection 1 3

Parasites

Protozoa-muscle 3

Metazoan parasites:

Nematode - kidney 14 5

Nematode - blubber 9

Nematode - lung 11 2

Nematode - stomach 5

Trematode - liver 1

Cardiopulmonary disease 6 2

Inflammatory, misc. 1 2

Total 3 33 31

Source: Burek-Huntington et al. 2013.

through the ingestion of infected prey and often do not affect the host’s general health. Parasitic 

disease in captive animals is rarely seen due to the use of anthelminthics (i.e., drugs that expel 

parasitic worms from the body) and the practice of feeding restaurant-quality, frozen fish, which 

disrupts parasitic life cycles.

Fungi: Fungal organisms, including candida and Aspergillus fumigatus, have been 

implicated in the deaths of some captive animals but may be related to the use of antibiotics,

which, in addition to suppressing pathogenic bacteria, can also suppress normal flora that helps 

protect against fungal diseases. Additionally, captive facilities put belugas in closer proximity to 

environmental sources of fungal organisms, which are not normally found in open waters. 

However, fungal and other infectious organisms can be liberated during major earth-moving 

operations and may travel airborne some distance (Bowenkamp et al. 2001). There have been no 

reports of fungus-related death in Cook Inlet or SLE animals.

Harmful Algal Blooms (HABs): HABs have the potential of producing toxins that can kill 

marine mammals or make them more susceptible to death due to other causes, such as predation 

or boat strikes. Additionally, algal blooms are expected to increase with the warmer ocean 

conditions anticipated for Alaska in the coming years. As part of Food and Drug Administration 

requirements, the ADEC tests all commercial shellfish for Paralytic Shellfish Poisoning (caused 

by harmful algae) as part of their Marine Biotoxin Program. However, commercial shellfish 

harvesting in Cook Inlet is limited to the area between Polly Creek and Crescent River in upper 

Cook Inlet and to Kachemak Bay in lower Cook Inlet, leaving large areas unmonitored. 

Furthermore, ADEC does not routinely test for other harmful algal toxins. The Kachemak Bay 

Research Reserve participates in NOAA’s Phytoplankton Monitoring Network, though 

participation is relatively new and has been sporadic. A high-mortality event of SLE belugas was 

caused by an algal bloom in 2008 (Lair et al. 2009).
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Findings of disease in other marine mammals in Cook Inlet: There is limited evidence of 

disease transfers among marine mammal species. However, because beluga and other species 

may be exposed to the same disease source via prey or the environment, understanding 

conditions that affect other marine mammals in Cook Inlet could provide insight into pathogens 

that might also affect belugas. Stranded harbor seals (n = 59) found in Cook Inlet during 1997 to 

2011 were screened for a variety of diseases (Goertz, in prep). Most seals were young of the year 

and found by serology to be negative for evidence of exposure to the following diseases: avian 

influenza, canine distemper virus, dolphin morbillivirus, porpoise morbillivirus, Leptospira 

canicola, L. grippotyphosa, L. pomona, Neospora, Sarcocystis, and Toxoplasma. One animal 

tested positive for antibodies against Brucella spp. and another was positive for phocine 

distemper virus. A few animals tested positive for antibodies to seal herpesvirus-1, L. Bratislava,

L. hardjo, and L. icterohemorrhagiae. All titers were stable or declining, suggesting waning 

maternally derived antibodies, except one animal had an increasing titer for seal herpesvirus-1. 

Fecal pathogen screenings yielded low levels of pathogenic and opportunistic bacteria, though 

none of concern for seal health. Causes of mortality and morbidity of Northern sea otters in Cook 

Inlet have also been intensely investigated, in part because of an unusual mortality event in lower 

Cook Inlet involving a streptococcal infection associated with heart damage, encephalitis, and 

sepsis. The source of the highly pathogenic bacteria and the conditions that may predispose sea 

otters to infection were not determined (Counihan-Edgar et al. 2012).

3. Trauma

Trauma was the cause of death in three (9%) of the cases that formed the basis of the 

mortality review in Cook Inlet (Burek-Huntington et al. 2013); two cases involved killer whale 

interactions, and one was blunt trauma from an unknown source. Two lactating females were 

found dead with rake marks consistent with killer whale attacks, following an observed 

interaction between killer whales and a large group of belugas on 23–26 of September 2000 (Vos 

et al. 2005). Only one of these lactating females was necropsied and included in the mortality 

review. Another adult female found in 2007 had extensive blunt trauma, and the final trauma 

case was coded based on tissues collected in September 2008 from the site of a witnessed killer 

whale attack on a beluga. Net entanglements or propeller injuries were not confirmed in 

nonspecific trauma cases, which may have been due to the poor carcass conditions. Photoidentification studies have documented several live CI belugas with scars consistent with 

propeller injuries and rake marks (LGL 2009). Shelden et al. (2003) estimated killer whales kill 

an average of one beluga/year, although this could be an underestimate. Additional information 

about killer whale interactions is included in Sections II.D.1.and III.A.9. Of the 6% of SLE 

deaths attributed to trauma, the majority were due to boat strike (S. Lair, pers. comm. to C. 

Goertz). One beluga from an aquarium was euthanized due to complications associated with a 

mandibular infection secondary to a traumatic injury (L. Dunn, pers. comm. to C. Goertz).

4. Nutritional Stress

Six belugas from Cook Inlet included in the mortality review were in poor body condition; 

namely, they were so thin that poor nutrition was considered either the cause of, or a contributing 

factor to, death (Burek-Huntington et al. 2013). One of the contributory cases involved a fetus 

with no measurable blubber layer, implying poor nutritional status of the mother. Causes of poor 

nutrition could be due to lack of appropriate prey, inability to obtain prey due to debilitation 

from secondary injury or infection, or a disease process itself. Most of these animals were young; 
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IX-69

only one was a mature whale. This category was not used in assigning cause of death in the SLE 

data that were provided; however, primary starvation is being considered as a cause of death in 

some cases currently assigned to the “other” category (S. Lair, pers. comm. to C. Goertz).

5. Degenerative Conditions

Cardiomyopathy, or heart damage, was noted but not considered a cause of, or contribution 

to, death in three older CI belugas and may have been age related. Ruptured vessels have been 

diagnosed in a captive animal with an aortic rupture (Bowenkamp et al. 2001) and in three SLE 

adult males with pulmonary trunk aneurysms (Martineau et al. 1986). Central nervous system 

abnormalities, namely encephalomalacia (softening of the brain) and encephalopathy (brain 

degeneration) of unknown cause, have been diagnosed in captive animals (L. Dunn, pers. comm. 

to C. Goertz). Due to the difficulties involved in opening a beluga skull in the field, it is rare that 

the brain of CI beluga is examined.

6. Miscellaneous

Ice entrapment: While reported in other cetaceans and other populations of belugas 

(Armstrong 1985, Heide-Jørgensen et al. 2002), there have not been reports of ice entrapment of 

CI belugas nor of mortalities that may have been due to such an event. Given the environmental 

conditions during the winter and decreased human presence in the Inlet, such an event may go 

unnoticed. 

Cancer: Cancer is a major cause of mortality in SLE beluga (15%) and may relate to their 

heavy contaminant loads (Martineau et al. 2002). Cancers have also been observed in captive 

belugas (Ridgway et al. 2002) and accounted for 5% of the deaths in oceanaria (L. Dunn, pers. 

comm. to C. Goertz). There have been no reports of cancer in CI belugas.
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Cook Inlet Beluga Whale IX. APPENDICES

Recovery Plan I – Common and Scientific Names

IX-71

I. Common and Scientific Names of Species

The following is a list of common and scientific names of species identified in this recovery 

plan.

Common Name Scientific Name

Amphipod Crustaceans, Order Amphipoda

Beluga whale Delphinapterus leucas

Blue whale Balaenoptera musculus

Bottlenose dolphin Tursiops truncatus

Budgerigar Melopsittacus undulates

Butter sole Isopsetta isolepis

California sea lion Zalophus californianus

Capelin Mallotus villosus

Chinook (king) salmon Oncorhynchus tshawytscha

Chum salmon Oncorhynchus keta

Clams Animals of the class Bivalvia

Coho salmon Oncorhynchus kisutch

Cuvier's beaked whale Ziphius cavirostris

Dall’s porpoise Phocoenoides dalli

Eulachon Thaleichthys pacificus

Flathead sole Hippoglossoides elassodon

Gray whale Eschrichtius robustus

Grayling Thymallus thymallus

Great white shark Carcharodon carcharias

Greenland shark Somniosus microcephalus

Harbor porpoise Phocoena phocoena

Harbor seal Phoca vitulina

Hermit crab Crabs, superfamily Paguroidea

Humpback whale Megaptera novaeangliae

Killer whale Orcinus orca

Longfin smelt Spirinchus thaleichthys

Minke whale Balaenoptera acutorostrata

Narwhal Monodon monoceros

North Atlantic right whale Eubalaena glacialis

Northern pike Esox lucius

Northern shrimp Pandalus borealis

Pacific cod Gadus macrocephalus

Pacific halibut Hippoglossus stenolepis
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Recovery Plan I – Common and Scientific Names

IX-72

Common Name Scientific Name

Pacific herring Clupea pallasi

Pacific sandfish Trichodon trichodon

Pacific sandlance Ammodytes hexapterus

Pacific sleeper shark Somnoisus pacificus

Pacific staghorn sculpin Leptocottus armatus

Pacific tomcod Microgadus proximus

Pink salmon Oncorhynchus gorbuscha

Polar bear Ursus maritimus

Red king crab Paralithodes camtschatica

Saffron cod Eleginus gracilis

Salmon shark Lamna ditropis

Sea otter Enhydra lutris

Snake prickleback Lumpenus sagitta

Sockeye salmon Oncorhynchus nerka

Spiny dogfish Squalus suckleyi

Sponges Animals of the phylum Porifera

Starry flounder Platichthys stellatus

Steller sea lion Eumetopias jubatus

Tanner crab Chionoecetes bairdi

Trout Freshwater fish, subfamily Salmoninae

Walleye pollock Theragra chalcogramma

Weathervane scallops Patinopecten caurinus

Whitefish Freshwater fish, subfamily Coregoninae

Yellowfin sole Limanda aspera