Aerial Surveys of Endangered

Whales in the Beaufort Sea,

Fall 2000

OCS Study

MMS 2002-014

By Stephen D. Treacy, Research Manager

MMS Bowhead Whale Aerial Survey

U.S. Department of the Interior

Minerals Management Service Anchorage, Alaska

Alaska OCS Region 2002
i

ABSTRACT

This report describes field activities and data analyses for aerial surveys of bowhead whales conducted during

Fall 2000 (1 September-19 October) in the Beaufort Sea, primarily between 140W. and 157W. longitudes

south of 72N. latitude.

During Fall 2000, general ice cover during September and October was the 28th-mildest open-water season

(1953-2000). There were 89 sightings for a total of 193 bowhead whales counted during Fall 2000. 

Additionally, 4 gray whales, 266 beluga whales, 35 bearded seals, 243 ringed seals, 23 polar bears, and 28

sets of polar bear tracks were observed during 89.89 hours of survey effort that included 46.54 hours on

randomized transects. The initial sighting of bowhead whales in Alaskan waters occurred on 1 September,

when 3 bowheads were observed swimming in an easterly direction northeast of Deadhorse. Of the 193

bowheads observed, half (median) had been counted by 12 September. The peak count (mode) of 88

bowheads also occurred on 12 September, when 77 of these whales were observed feeding next to shore

between Dease Inlet and Smith Bay, Alaska. The last sighting of bowhead whales was made on 11 October

when 5 whales were observed swimming in a westerly direction near Cape Halkett, Alaska.

The axis of bowhead whale sightings in the West Region was much nearer to shore during Fall 2000 (11.0

km median distance) than for any single year, 1982-2000, and much less than the cumulative median (32.5

km). Likewise, the mean distance from shore for West-Region bowheads in 2000 (17.7 km) was less than

for any single year and much less than the cumulative mean (35.4 km). The Tukey test showed that WestRegion bowheads in 2000 migrated significantly (p<0.05) nearer to shore than for most (>9) other years.

Analysis of sighting rates showed that bowhead whales occur farther offshore in heavy-ice years during fall

migrations across the Central Alaskan Beaufort Sea (142W. to 155W. longitudes). Bowheads generally

occupy nearshore waters in years of light sea-ice severity, somewhat more offshore waters in moderate ice

years, and are even farther offshore in heavy ice years. While factors other than sea ice may have localized

effects on site-specific distributions, broad-area distributions of bowhead whale sightings in the central

Alaskan Beaufort Sea are related to overall sea-ice severity. This relationship is more geographically

restricted than previously noted.

An ANOVA of cumulative distances of bowhead whale sightings from a normalized shoreline in heavy,

moderate, and light sea-ice categories over a 19-year period (1982-2000) showed significant differences

(F=143.8 (2, 1294); p<0.0001). Post-hoc testing using both the Scheffe Test and Tukey HSD test for unequal

sample sizes indicated significant differences (p<0.0001) between the distances of bowhead whale sightings

from a normalized shoreline under each pair of sea-ice conditions.
iii

ACKNOWLEDGMENTS

Project Management

Cleveland J. Cowles, Ph.D., Supervisor

Stephen D. Treacy, Research Manager

Minerals Management Service (MMS) Project Field Science

Name Position Fall 2000

Stephen D. Treacy Research Manager Flights 1-22

Donald Hansen Team Leader Flights 23-28

Kyle Monkelien Data Recorder/Observer Flights 1-3

Kristopher Nuttall Data Recorder-Observer Flights 4-22

Caryn Smith Data-Recorder-Observer Flights 23-28

Linda Reeves Primary Observer Flights 1-8

Charles Monnett, Ph.D. Primary Observer Flights 9-24

Joel Hubbard, Ph.D. Primary Observer Flights 25-28

MMS Bowhead Whale Aerial Survey Project (BWASP) Field Support

Stephen D. Treacy MMS Contracting Officer’s Technical Representative: MMS/Office of Aircraft

Services (OAS) Interagency Agreement 05052

Tom Murrell Data-Collection System Developer

Kyle Monkelien Field Equipment Coordinator

Linda Reeves Field Support Coordinator

Report Production

Ian Moore Mapping System Developer (ArcView 3.1A)

Matt Heller Mapping System Consultant (ArcView 3.2A)

Jody Lindemann Manuscript submission to printer

National Marine Fisheries Service (NMFS) Liaison

Brad Smith, NMFS, Anchorage, Alaska

We acknowledge the U.S. Department of the Interior (USDOI), OAS, for making all aircraft arrangements and

for monitoring satellite tracking of survey flights; Skip Haase, Randy Leypoldt, Mike Mercier, Eric Moss, and

Jake Shields (ERA Aviation) for piloting the Twin Otter in 2000.

We appreciate review comments on this and/or previous project reports by NMFS, State of Alaska, North

Slope Borough (NSB), Indigenous People's Council for Marine Mammals, and National Ice Center.

The project acknowledges the National Ice Center for draft sea-ice-severity rankings and for sea-ice

concentrations in ARC/INFO format (www.natice.noaa.gov). We appreciate administrative support provided

by Geraldine Taylor. Ann Treacy contributed the cover illustration.
v

CONTENTS

Page

ABSTRACT.................................................................................................................................................... i

ACKNOWLEDGMENTS .............................................................................................................................. iii

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

II. METHODS AND MATERIALS................................................................................................................. 3

A. Study Area ................................................................................................................................. 3

B. Equipment ................................................................................................................................. 3

C. Aerial-Survey Design................................................................................................................ 5

D. Survey-Flight Procedures........................................................................................................ 6

E. Data Entry.................................................................................................................................. 6

F. General Data Analyses ............................................................................................................. 6

G. Analysis of the Bowhead Whale Migration Corridor ............................................................ 9

H. Oceanographic Regions ........................................................................................................ 10

III. FALL 2000 RESULTS .......................................................................................................................... 15

A. Environmental Conditions..................................................................................................... 15

B. Survey Effort ........................................................................................................................... 15

C. Bowhead Whale (Balaena mysticetus) Observations......................................................... 15

 1. Sighting Summary ..................................................................................................... 15

 2. Sighting Rates and Distance from Shore ................................................................ 27

3. Migration Timing ........................................................................................................ 27

4. Habitat Associations.................................................................................................. 31

5. Behaviors.................................................................................................................... 31

D. Other Marine Mammal Observations.................................................................................... 31

1. Gray Whale (Eschrichtius robustus)........................................................................ 31

2. Beluga Whale (Delphinapterus leucas).................................................................... 31

3. Bearded Seal (Erignathus barbatus nauticus) ........................................................ 31

4. Ringed Seal (Pusa hispida hispida) ......................................................................... 31

5. Walrus (Odobenus rosmarus divergens) ................................................................ 31

6. Unidentified Cetaceans and Pinnipeds.................................................................... 31

7. Polar Bear (Ursus maritimus marinus) .................................................................... 37

IV. INTERANNUAL RESULTS .................................................................................................................. 41

A. Statistical Analyses of Bowhead Whale Sighting Distribution (1982-2000)...................... 41

1. Central Tendency Statistics - Distance from Shore ............................................... 41

2. Central Tendency Statistics - Water Depth ............................................................. 41

3. ANOVA – Distance from Shore ................................................................................. 41

4. Tukey HSD Test - Distance from Shore ................................................................... 41

B. General Sea Ice Severity (1979-2000) ................................................................................... 47

C. General Sea Ice Severity and Bowhead Whale Sighting Rates (1982-2000)..................... 47

D. Key Results Summary............................................................................................................ 53

V. DISCUSSION......................................................................................................................................... 55

A. Management Use of Real-Time Field Information ............................................................... 55

B. Management Use of Interannual Monitoring ....................................................................... 55

C. Conclusions ............................................................................................................................ 56

D. Field Coordination and Other Information Support............................................................ 56

VI. LITERATURE CITED ........................................................................................................................... 59
vi

APPENDICES

Appendix A: Fall 2000 Ice Concentration Maps for the Beaufort Sea..................................... 63

Appendix B: Fall 2000 Bowhead Whale Sighting Data............................................................. 73

Appendix C: Fall 2000 Daily Flight Summaries ......................................................................... 79

Appendix D: Glossary of Abbreviations, Acronyms, and Initialisms.................................... 109
vii

LIST OF FIGURES

Figure

Number Title Page

1 Study Area Showing Survey Blocks.............................................................................................. 4

2 East and West Regions and Selected Isobaths.......................................................................... 11

3 Combined Flight Tracks, 1-15 September 2000......................................................................... 19

4 Combined Flight Tracks, 16-30 September 2000....................................................................... 20

5 Combined Flight Tracks, 1-15 October 2000.............................................................................. 21

6 Combined Flight Tracks, 16-19 October 2000............................................................................ 22

7 Map of Bowhead Whale Sightings, 1-15 September 2000 ......................................................... 23

8 Map of Bowhead Whale Sightings, 16-30 September 2000 ....................................................... 24

9 Map of Bowhead Whale Sightings, 1-15 October 2000.............................................................. 25

10 Map of Bowhead Whale Sightings, Fall 2000 ............................................................................. 26

11 Sighting Rates of Bowhead Whales on Transect, Fall 2000....................................................... 29

12 Bowhead Whale Sightings on Transect during Fall 2000, Showing Mean Distance

from a Normalized Shoreline ...................................................................................................... 30

13 Map of Gray Whale Sightings, Fall 2000 .................................................................................... 33

14 Map of Beluga Whale Sightings, Fall 2000................................................................................. 34

15 Map of Bearded Seal Sightings, Fall 2000.................................................................................. 35

16 Map of Ringed Seal Sightings, Fall 2000.................................................................................... 36

17 Map of Polar Bear Sightings, Fall 2000....................................................................................... 38

18 Map of Polar Bear Tracks, Fall 2000 .......................................................................................... 39

19 Fall Sighting Rates of Bowhead Whales on Transect, Years with Heavy Sea-Ice Severity ....... 48

20 Fall Sighting Rates of Bowhead Whales on Transect, Years with Moderate Sea-Ice Severity .. 49

21 Fall Sighting Rates of Bowhead Whales on Transect, Years with Light Sea-Ice Severity.......... 50

22 Fall Sighting Rates of Bowhead Whales on Transect, Years with Heavy, Moderate,

and Light Sea-Ice Severity.......................................................................................................... 51
ix

LIST OF TABLES

Table

Number Title Page

1 Operational Definitions of Observed Whale Behaviors................................................................. 7

2 Aerial-Survey Effort in the Beaufort Sea, 1 September-19 October 2000,

by Survey Flight........................................................................................................................... 16

3 Summary of Marine Mammal Sightings, 1 September-19 October 2000,

by Survey Flight........................................................................................................................... 17

4 Number of Sightings and Total Bowhead Whales Observed per Hour,

1 September-19 October 2000, by Flight Day............................................................................. 28

5 Semimonthly Summary of Bowhead Whales Observed, by Percent Ice Cover

Present at Sighting Location, Fall 2000 ...................................................................................... 32

6 Semimonthly Summary of Bowhead Whales Observed, by Behavioral Category,

Fall 2000 ..................................................................................................................................... 32

7 Central-Tendency Statistics for Distance from Shore to Random Sightings of Bowhead

Whales (September-October), by Year and Region, 1982-2000................................................ 42

8 Central-Tendency Statistics for Water Depth at Random Sightings of Bowhead

Whales (September-October), by Year and Region, 1982-2000................................................ 44
1

I. INTRODUCTION

In 1953, the Outer Continental Shelf Lands Act (OCSLA) (43 USC 1331-1356) charged the Secretary of the

Interior with the responsibility for administering minerals exploration and development of the OCS. The Act

empowered the Secretary to formulate regulations so that its provisions might be met. The OCSLA

Amendments of 1978 (43 USC 1802) established a policy for the management of oil and natural gas in the

OCS and for protection of the marine and coastal environments. The amended OCSLA states that the

Secretary of the Interior shall conduct studies in areas or regions of sales to ascertain the “environmental

impacts on the marine and coastal environments of the outer Continental Shelf and the coastal areas which

may be affected by oil and gas development” (43 USC 1346).

Subsequent to the passage of the OCSLA, the Secretary of the Interior designated the Bureau of Land

Management (BLM) as the administrative agency responsible for leasing submerged Federal lands and the

Conservation Division of the U.S. Geological Survey for classification and evaluation of submerged Federal

lands and regulation of exploration and production. In 1982, the Minerals Management Service (MMS)

assumed these responsibilities.

To provide information used in environmental impact statements and environmental assessments under the

National Environmental Policy Act of 1969 (42 USC 4321-4347), and to assure protection of marine mammals

under the Marine Mammal Protection Act of 1972 (16 USC 1361-1407) and the Endangered Species Act

(ESA) of 1973 (16 USC 1531-1543), BLM funded numerous studies involving acquisition and analysis of

marine mammal and other environmental data.

In June 1978, BLM entered into an ESA Section 7 consultation with NMFS. The purpose of the consultation

was to determine the likely effects of the proposed Beaufort Sea Oil and Gas Lease Sale on endangered

bowhead (Balaena mysticetus) and gray (Eschrichtius robustus) whales. The NMFS determined that

insufficient information existed to conclude whether the proposed Beaufort Sea sale was or was not likely to

jeopardize the continued existence of bowhead and gray whales. In August 1978, NMFS recommended

studies to BLM that would fill the information needs identified during the Section 7 consultation. Subsequent

biological opinions for leasing and exploration in the Beaufort Sea (Sales 71, 87, and 97) and the 1988 Arctic

Region Biological Opinion (ARBO), used for Beaufort and Chukchi Sea sales (Sales 124, 126, 144, and 170),

recommended continuing studies of whale distribution and OCS-industry effects on bowhead whales (USDOC,

NOAA, NMFS, 1982, 1983, 1987, 1988) and monitoring of bowhead whale presence during periods when

geophysical exploration and drilling are occurring. The current ARBO, issued by NMFS in 2001 for leasing

and exploration in the Beaufort Sea, also recommends that whale distribution studies during the fall migration

continue, along with acoustic monitoring studies to describe the impact of exploration activities on the

migration path of bowhead whales in the Beaufort Sea.

Following several years when drilling was limited to the period 1 November through 31 March (USDOI, MMS,

1979), a variable 2-month seasonal-drilling restriction on fall exploratory activity in the joint Federal/State

Beaufort Sea sale area was implemented. The period of restriction would vary depending on bowhead whale

presence, and “this determination would require development of a monitoring program. . ..” (USDOI, MMS,

1982). Subsequently, MMS (Alaska OCS Region) adopted an endangered whale-monitoring plan that

required aerial surveys. The Diapir Field Sale 87 Notice of Sale (NOS) (1984) states that “Bowhead whales

will be monitored by the Government, the lessee, or both to determine their locations relative to operational

sites as they migrate through or adjacent to the sale area” (USDOI, MMS, 1984). Subsequent lease sales

in the Beaufort Sea (Sales 97, 124, 144, and 170) did not include a seasonal drilling restriction but the NOS

for each contained an Information to Lessees clause that “MMS intends to continue its areawide endangered

whale monitoring program in the Beaufort Sea during exploration activities” (USDOI, MMS, 1988, 1991, 1996,

1998). Information gathered is used to help determine the extent, if any, of adverse effects on the species.

From 1979 to 1987, the MMS (formerly BLM) funded annual monitoring of endangered whales in arctic waters

under Interagency Agreements with the Naval Ocean Systems Center and through subcontracts to SEACO,

Inc. On 15 April 1987, a proposal for MMS scientists to conduct aerial surveys of endangered whales was

approved by the Associate Director for Offshore Minerals Management. The MMS uses agency personnel

to perform fieldwork and reporting activities for the Beaufort Sea on an annual basis. Previous survey reports
2

are available for inspection at the Minerals Management Service, Alaska OCS Region, Resource Center, 949

East 36th Avenue, Anchorage, Alaska 99508-4363.

The goals of the ongoing program for monitoring endangered whales are to:

1. Provide real-time data to MMS and NMFS on the general progress of the fall migration of bowhead whales

across the Alaskan Beaufort Sea, for use in implementing overall limitations on seasonal drilling and

geological/geophysical exploration;

2. Monitor temporal and spatial trends in the distribution, relative abundance, habitat, and behaviors (e.g.,

feeding) of endangered whales in arctic waters;

3. Define the axis of the fall bowhead migration and analyze for significant interyear differences and long-term

trends in the distance from shore and water depth at which whales migrate;

4. Provide an objective wide-area context for management interpretation of the overall fall migration of

bowhead whales and site-specific study results;

5. Record and map beluga whale distribution and incidental sightings of other marine mammals; and

6. Determine seasonal distribution of endangered whales in other planning areas of interest to MMS.
3

II. METHODS AND MATERIALS

A. Study Area

The annual survey program has been based on a design of random field transects within established

geographic blocks overlapping or near Chukchi and Beaufort Sea sale areas offshore of Alaska. The present

study, which was focused on the fall bowhead whale migrations during 2000, included Beaufort Sea Survey

Blocks 1 through 12 (Fig. 1) between 140W. and 157W. longitude south of 72N. latitude.

A large-scale Beaufort Gyre moves waters clockwise from the Canadian Basin westward in the deeper

offshore regions. Nearshore surface currents tend to follow local wind patterns and bathymetry, moving from

the east in winter, with an onshore component, and to the west in summer, with an offshore component

(Brower et al., 1988). There is recent evidence for the existence of two regimes or climate states for arctic

atmospheric-ice-ocean circulation. Based on analysis of modeled sea level and ice motion, wind-driven

motion in the Arctic was found to alternate between anticyclonic and cyclonic circulation, with each regime

persisting for 5-7 years (Proshutinsky and Johnson, 1997; Johnson et al., 1999).

In the Beaufort Sea, landfast ice forms during the fall and may eventually extend up to 50 kilometers (km)

offshore by the end of winter (Norton and Weller, 1984). The pack ice, which includes multiyear ice averaging

4 meters (m) in thickness, with pressure ridges up to 50 m thick (Norton and Weller, 1984), becomes

contiguous with the new and fast ice in late fall—effectively closing off the migration corridor to westbound

bowhead whales. From early November to mid-May, the Beaufort Sea normally remains almost totally

covered by ice considered too thick for whales to penetrate. In mid-May, a recurring flaw lead can form just

seaward of the stable fast ice, followed by decreasing ice concentrations (LaBelle et al., 1983) and large areas

of open water in summer.

Local weather patterns affect the frequency and effectiveness of all marine aerial surveys. The present study

area is in the arctic climate zone, with mean temperatures at the Alaskan Beaufort Sea coast communities

of Barrow, Lonely, Oliktok, and Barter Island from -0.9C to -0.1C during September and from -9.7C to -

8.5C during October. Precipitation in these communities occurred an average of 10 to 34 percent of the time

during September (snow with some rain) and 13 to 43 percent during October (almost all snow), with the

heaviest precipitation at Barrow and Barter Island during both months. Fog (without precipitation) reduces

visibility approximately 11 to 19 percent of the time during September and 6 to 8 percent of the time during

October. Mean windspeed in the same communities is from 5 to 6 m per second during September and 5

to 7 m per second during October (Brower et al., 1988).

Sea state is another environmental factor affecting visibility during aerial surveys. Surface waters in the

Beaufort Sea are driven primarily by wind. Ocean waves are generally from northerly or easterly directions

during September and October, during which time the ice pack continues to limit fetch. Because of the pack

ice, significant wave heights are reduced by a factor of 4 from heights that would otherwise be expected during

the open-water season. Wave heights greater than 0.5 m occurred in 23.9 to 38.9 percent of observations

during September and 14.1 to 37.4 percent during October, with the greater percentage of larger waves (>0.5

m) reported for the eastern third of the study area during both months. Wave heights greater than 3.5 m are

not reported within the study area during September or October (Brower, 1988).

The study area contains sufficient zooplankton to support some feeding by bowhead whales. The availability

of zooplankton during the fall would be expected to vary between years, geographic locations, and water

depths in response to ambient oceanographic conditions. In September 1985 and 1986, average zooplankton

biomass in the Alaskan Beaufort Sea east of 144W. longitude was highest south of the 50-m isobath in

subsurface water (LGL Ecological Research Associates, Inc., 1987).

B. Equipment

The survey aircraft was a de Havilland Twin Otter Series 300 (call sign: N321EA). The aircraft was equipped

with two medium-size bubble windows behind the cabin bulkhead and one on the aft starboard side that

afforded complete trackline viewing. The pilot and copilot seats provided good forward and side viewing. 


























  



















	
























	











	












	











	














	






	


	



	 

 





 

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Each observer was issued a hand-held clinometer (Suunto) for measuring the angle of inclination to the

sighting location of endangered whales. Observers and pilots were linked to common communication

systems, and commentary could be recorded. The aircraft's maximum time aloft under normal survey load

was extended to approximately 8 hours (hr) through the use of a supplemental onboard fuel tank.

A portable Gateway Solo 5100 SE laptop computing system was used aboard the aircraft to store and analyze

flight and observational data. From 30 August through 15 September, the computer system was connected

to a local Garmin III Global Positioning System (GPS) with external aircraft antenna. When the data

connection to this GPS failed on 16 September, the project switched to inputting latitude, longitude, and flight

altitude into the computer through a standard serial connection from the aircraft’s Flight Management System

5000, Model GPS-505. A custom moving-map program developed by MMS project personnel in Visual Basic

permitted surveyors to view the aircraft’s trackline in real time.

Onboard safety equipment included an impact-triggered emergency locator transmitter installed in the aircraft,

a 6-person Switlik Search and Rescue Life Raft equipped with a portable Personal Locator Beacon and

desalination pump, a portable ICOM A3 Sport aircraft-band transceiver, an emergency Magellan 3000 GPS,

White dry suits, and emergency flight helmets.

In 2000, we used both SkyCell and Windstream satellite flight-following systems for tracking the project aircraft

over the Alaskan Beaufort Sea. The OAS obtained current flight information in the form of maps for visual

tracking of the survey aircraft. In addition to satellite flight following, the onboard transponder was set at a

discrete identification code for radar tracking by air-traffic-control personnel.

C. Aerial-Survey Design

Aerial surveys were based out of Deadhorse, Alaska, from 1 September through 17 October during 2000.

 Field schedules were designed to monitor the progress of fall bowhead migrations across the Alaskan

Beaufort Sea. All bowhead (and beluga) whales observed were recorded, along with incidental sightings of

other marine mammals. Particular emphasis was placed on regional surveys to assess large-area shifts in

the migration pathway of bowhead whales and on the coordination of effort and management of data

necessary to support seasonal offshore-drilling and seismic-exploration regulations.

Daily flight patterns were based on sets of unique transect grids computer-generated for each survey block.

 Transect grids were derived by dividing each survey block into sections 30 minutes of longitude across. One

of the minute marks along the northern edge of each section was selected at random then connected by a

straight line to a similarly selected endpoint along the southern edge of that same section. This procedure

was followed for all sections of that survey block. These transect legs were then connected alternately at their

northernmost or southernmost ends to produce one continuous flight grid within each survey block. The use

of random-transect grids is a requirement for subsequent analyses of the bowhead migration corridor based

on line-transect theory (Cochran, 1963).

The selection of the survey blocks to be flown on a given day was nonrandom, based primarily on criteria such

as reported or observed weather conditions over the study area and the level of offshore oil industry activity

in various areas. Weather permitting, the project attempted to distribute effort fairly evenly east-to-west across

the entire study area. It also used a semimonthly flight-hour goal for each survey block allocated

proportionately for survey blocks east of 154W. longitude and semimonthly time periods based on relative

abundance of bowhead whales as determined from earlier fall migrations (1979-1986). Such allocations,

detailed in our Project Management Plan (USDOI, MMS, 2000), greatly favor survey coverage in inshore

Survey Blocks 1 through 7 and 11 (Fig. 1), since bowheads were rarely sighted north of these blocks in

previous surveys. The purpose of these survey-effort allocations was to increase the sample size (n) of whale

sightings within the primary migration corridor, thus increasing the power of statistical analysis within these

inshore blocks. Only data from random-transect legs were used to analyze the migration axis, using a linetransect model.
6

D. Survey-Flight Procedures

During a typical flight, a “search” leg was flown to the target survey block, beginning a series of random-

“transect” legs (above) joined together by “connect” legs, followed by a search leg back to Deadhorse. 

Surveys generally were flown at a target altitude of 458 m. Weather permitting, this altitude was maintained

in order to maximize visibility and to minimize potential disturbance to marine mammals. Flights were normally

aborted when cloud ceilings were consistently less than 305 m or the wind force was consistently above

Beaufort 4.

Port observers included a Primary Observer, whose field of vision through a bubble window included the

trackline directly below the aircraft to the horizon, the Pilot, and an occasional secondary observer-visitor,

stationed aft at a flat window. Starboard observers included a Data Recorder-Observer, whose field of vision

through a bubble window was particularly focused on guarding the trackline, as well as a Team Leader and

a second Pilot, who were alternately stationed at an aft bubble window and the copilot’s seat. A clinometer

was used to measure the angle of inclination to each sighting of endangered whales when the initial sighting

location was abeam of the aircraft.

When bowheads were encountered while surveying a transect line, the aircraft sometimes diverted from

transect for brief (<10-minute) periods and circled the whales to observe behavior, obtain better estimates of

their numbers, and determine whether calves were present. Any new sightings of whales made while circling

were not counted as “on transect.” Likewise, sightings made while en route to transect grids were counted

as “on search”.

E. Data Entry

A customized computer data-entry form developed by MMS project personnel was used to record all data in

database format (Access 97). A multi-columnar data table permitted several entries of sighting and positionupdate data to be logged and edited simultaneously. The data-entry form is menu-driven, facilitating entry

of a complete data sequence for sightings of whales. These data included date, time, latitude, longitude,

altitude, aircraft heading, reason for entry, species, total number, observer, swim direction (magnetic),

clinometer angle, calf number, behavior, sighting cue, predominant size, habitat, swim speed, repeat sighting,

and response to aircraft. Reduced data sequences were used when recording other marine mammals. 

Position-update data on sky conditions, visual impediments, visibility left and right, percent ice coverage, ice

type, and wind force were entered at sightings, turning points, when changes in environmental conditions were

observed, and otherwise within 10-minute intervals. Entries were simultaneously printed out in hard copy.

The behavior, swim speed, and swim direction for observed whales represent what the pod as a whole was

doing at the time it was first sighted. Behaviors were entered into one of 15 categories as noted on previous

surveys. These categories—breaching, cow-calf association, diving, feeding, flipper-slapping, log playing,

mating, milling, resting, rolling, spy-hopping, swimming, tail-slapping, thrashing, and underwater blowing—are

defined in Table 1. Swimming speed was subjectively estimated by observing the time it took a whale to swim

one body length. An observed swimming rate of one body length per minute corresponded to an estimated

speed of 1 km/hr. One body length per 30 seconds was estimated at 2 km/hr, and so on. Swimming speed

was recorded by relative category (i.e., still, 0 km/hr; slow, 0-2 km/hr; medium, 2-4 km/hr; or fast, >4 km/hr).

 Likewise, whale size was estimated relatively as calf (length less than half of accompanying adult), immature,

adult, or large adult. Swim direction was initially recorded in magnetic degrees, using the aircraft's compass.

Wind force was recorded according to the Beaufort scale outlined in Piloting, Seamanship, and Small Boat

Handling (Chapman, 1971). Ice type was identified using terminology presented in Naval Hydrographic Office

Publication Number 609 (USDOD, Navy, 1956). Average ice cover over a 1-2 km lateral distance from the

aircraft was estimated as a single percentage, regardless of ice type.

F. General Data Analyses

Preliminary field data analysis was performed by a computer program—developed by MMS project

personnel—that provided daily summations of marine mammals observed, plus calculation of time and
7

Table 1

Operational Definitions of Observed Whale Behaviors

Behavior Definition

Breaching Whale(s) launching upwards such that half to nearly all of the body is above the surface

before falling back into the water, usually on its side, creating an obvious splash.

Cow-Calf Calf nursing; cow-calf pairs swimming within 20 m of each other.

Diving Whale(s) changing swim direction or body orientation relative to the water surface,

resulting in submergence; may or may not include lifting the tail out of the water.

Feeding Whale(s) diving repeatedly in a fixed general area, sometimes with mud streaming from

the mouth and/or defecation observed upon surfacing. Feeding behavior is further

defined as synchronous diving and surfacing or echelon-formations at the surface with

swaths of clearer water behind the whale(s), or as surface swimming with mouth agape

FlipperSlappingWhale(s) floating on side, striking the water surface with pectoral flipper one or many

times; usually seen within groups or when the slapping whale is touching another whale.

Log-Playing Whale(s) milling or thrashing about in association with a floating log.

Mating Ventral-ventral orienting of two whales, often with one or more other whales present to

stabilize the mating pair. Mating is often seen within a group of milling whales. Pairs may

appear to hold each other with their pectoral flippers and may entwine their tails.

Milling Whale(s) swimming slowly at the surface in close proximity (within 100 m) to other

whales, often with varying headings.

Resting Whale(s) floating at the surface with head, or head and back exposed, showing no

movement; more commonly observed in heavy-ice conditions than in open water.

Rolling Whale(s) rotating on the longitudinal axis, sometimes associated with mating.

Spy-Hopping Whale(s) extending head vertically out of the water such that up to one-third of the body,

including the eye, is above the surface.

Swimming Whale(s) proceeding forward through the water propelled by tail pushes.

Tail-Slapping Whale(s) floating horizontally or head-downward in the water, waving tail back and forth

above the water and striking the water surface; usually seen in group situations.

Thrashing Whale(s) exhibiting rapid flexure or gyration in the water.

UnderwaterBlowingWhale(s) exhaling while submerged, thus creating a visible bubble.
9

distance on transect legs, connect legs, and general search portions of the flight. This analysis program

provided options for editing the data file, calculating summary values, and printing various flight synopses.

Tables showing the number of survey hours flown for individual days, half-months, months, or survey blocks

were subject to decimal-rounding errors and may or may not add up to the grand total shown for the entire

field season. For greatest accuracy and consistency, the total survey hours shown in tables was calculated

separately from the cumulative total minutes flown over the entire field season.

An index of relative abundance was derived as whales per unit effort (WPUE = number of whales counted per

hour of survey effort on transect, connect, and search). Sighting rates used in report tables were derived as

total sightings per unit effort (SPUE = whale pods sighted per hour of survey effort on transect, connect, and

search). Sighting rates were depicted on a gridded map representing pods sighted per kilometer of survey

effort while on northerly-southerly transects within each grid cell (5’ latitude by 15’ longitude).

The water depth at each bowhead sighting in the 1982-2000 database was derived from the International

Bathymetric Chart of the Arctic Ocean (IBCAO) containing grid cells 2.5 km square (website

http://www.ngdc.noaa.gov/mgg/bathymetry/arctic/arctic.html. Selected isobaths (10 m, 20 m, 30 m, 40 m,

50 m, 60 m, 100 m, 500 m, 1,000 m, 1,500 m, 2,000 m, 2,500 m, 3,000 m, and 3,500 m), also derived

from IBCAO data, were included in Figure 2 for visual reference.

The maps in this report were prepared with application software (ArcView 3.2A) based on Universal

Transverse Mercator Zone 6 (central meridian =147W. longitude, reference latitude 0.00000, false easting

500000.00000, false northing 0.00000, spheroid = GRS 80, scale factor = 0.99960). The natural coastline

was adopted from the State of Alaska, Department of Natural Resources.

Sea-ice concentrations were derived from the Beaufort Sea Ice Analysis provided by the National Ice Center

in Suitland, Maryland. The Beaufort Sea Ice Analysis shows average ice concentrations over the prior 2- to

3-day period based on visual, infrared, and synthetic-aperture-radar satellite imagery combined with

reconnaissance, ship, and shore observations, including sea-ice observations made by the project. Polygons

of ice concentrations in the Beaufort Sea bracketing the field seasons were downloaded from the National Ice

Center Internet web site for the western Arctic (http://www.natice. noaa.gov) and imported into ArcView. Total

sea-ice concentrations, regardless of ice type, were edited from these polygons and specially coded to

distinguish 0-percent, 1- to 19-percent, 20- to 39-percent, 40- to 59-percent, 60- to 79-percent, 80- to 94-

percent, or 95- to 100-percent ice cover.

Survey effort and observed bowhead distribution were plotted semimonthly over the Beaufort Sea study area.

 Overall fall sightings of beluga whales, as well as incidental sightings of other marine mammals, were

depicted on separate maps. Common and scientific names used for marine mammals in this report are taken

from Rice (1998).

Overall, whale sightings were shown on distribution maps and entered into relative-abundance analyses,

regardless of the type of survey leg (transect, search, or connect) being conducted or the prevailing

environmental conditions (sea state, ice cover, etc.) when the sightings were made. As with previous reports

in this series (Treacy, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, and 2000), sameday repeat sightings or sightings of dead marine mammals were not included in summary analyses or maps.

 Where tables and figures exclude certain data, such exclusions are indicated in the captions.

G. Analysis of the Bowhead Whale Migration Corridor

The corridor used by bowhead whales during their fall migration was analyzed both by the mean distance from

shore to whales sighted on randomized transects as well as mean water depth at random whale sightings.

 The analyses presented here were completed using StatisticaTM StatSoft, Version 5.1 and ArcView 3.2A. The

mean distance from shore at bowhead sightings between years were compared employing parametric

analysis of variance (ANOVA) and Tukey “honestly significant difference” (HSD) tests. The ANOVA tests the

hypothesis that distances from shore are the same among years. The Tukey HSD test is a multiple

comparison procedure that provides statistical comparison of means for any pair of years (Zar, 1984). 
10

Distance from shore is of particular interest to North Slope residents who rely on a successful harvest of

whales for subsistence purposes. Subsistence whalers generally agree that the farther offshore whales

migrate, the riskier whales are to hunt and the more likely carcasses will spoil before reaching the villages

(USDOI, MMS, 1997).

An analysis protocol specifying the use of median water depth to detect interannual shifts in the bowhead

migration route was initially described in Chapters 4.2.3 and 5.3.3 of “Beaufort Sea Monitoring Program

Workshop Synthesis and Sampling Design Recommendations” (Houghton, Segar, and Zeh, 1984). Because

of the bathymetry of the Alaskan Beaufort Sea, a seaward displacement of the fall-migration route would be

represented, via this analysis, as a shift to deeper water and a greater median depth.

The present analyses provide biological information needed to test the following null hypotheses

recommended by the above workshop:

Ho1: The axis of the fall migration of bowhead whales will not be altered during periods of increased OCS

oil and gas development activities in the Alaskan Beaufort Sea.

Ho2: Changes in bowhead migration patterns are not related to OCS oil and gas development activity.

To determine the usefulness of these analyses for detecting differences in distance from shore between years,

a preliminary power analysis was performed (Treacy, 1998).

H. Oceanographic Regions

To define the migration axis, a separate file was created for bowhead whale sightings made while on random

transects, regardless of distance from the transect line. Distance from shore and water depth at bowhead

whale sightings made during random transect aerial surveys in the Alaskan Beaufort Sea were analyzed for

two regions (Fig. 2), the boundaries of which correspond roughly to oceanographic patterns and the offshoreextent of sampling.

Oceanographic patterns common to waters offshore northern Alaska are reviewed in Moore and DeMaster

(1997). In brief, cold saline Bering Sea water and warm fresh Alaskan coastal water enter the Alaskan

Beaufort Sea through Barrow Canyon. Both water masses are identifiable on the outer shelf (seaward of 50

m) as the eastward flowing Beaufort undercurrent (Aagaard, 1984). Bering Sea water has been traced at least

as far east as Barter Island (~143W.), but the Alaskan coastal water mixes with ambient surface waters as

it moves eastward and is not clearly identifiable east of Prudhoe Bay (~147-148W.). Therefore, the

delineation between West-East regions for this analysis occurs at 148W., based upon association with

general patterns for these water masses.

The northern extent of each region is based upon survey effort. For example, the East Region extends from

140W. to 148W. and from the shore north to 7110’ N., except between 146W. and 148W. where the

region extends to 7120’N. The northern boundary for this region corresponds with boundaries of survey

blocks 6, 7 and 2 (Fig. 1): blocks with sufficient survey effort to support analyses (Treacy, 1997: Table 11).

 The West Region extends from 148W. to 156W. and from the shore north to 72N., except between 148W.

and 150W. where the region extends to 7120’N. due to the layout of Block 2. The eastern boundary

(140W.) is simply the easternmost longitude of the survey blocks. The western cutoff at 156W. limits the

analysis to bowheads seen in the Alaskan Beaufort Sea and avoids the influence of Barrow Canyon on

bowhead depth distribution.

The shoreline used for this analysis was ‘normalized’ from the actual Beaufort Sea shoreline to provide a

standardization of distance-from-shore measures regardless of the mapping software being used to depict

the distribution data. The ‘normalized’ shoreline was derived by connecting, with straight lines, eleven points

at various shoreline or barrier islands locations across Alaska’s North Slope between 156W. and 140W.


























  





















	











	












	











	














	





	


	



	 	























 

	





 






	







 

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13

(Fig. 2). The points used to ‘normalize’ the shoreline are as follows:

71.317N., 156.000W.

70.883N., 153.900W.

70.917N., 153.115W.

70.817N., 152.200W.

70.430N., 151.000W.

70.550N., 150.167W.

70.450N., 147.950W.

69.967N., 144.700W.

70.150N., 143.250W.

69.650N., 141.000W.

69.617N., 140.000W.
15

III. FALL 2000 RESULTS

A. Environmental Conditions

General ice coverage in the Alaskan Beaufort Sea (Appendix A) was fairly light during most of the Fall 2000.

 Ice coverage began to open up after 28 August. During the first half of September, the western half of the

study area was relatively ice-free, whereas the eastern half had 1-19% inshore concentrations, with heavier

offshore concentrations. During the latter half of September, sea ice across the study area was either ice-free

or nearly so (1-9%), except for a narrow strip of shore-fast ice at the end of the month. By 6 October, a small

area between Deadhorse and Dease Inlet, Alaska was still ice-free, with fairly low concentrations of ice

elsewhere in the study area. By mid-October, heavy ice concentrations prevailed along shore and offshore,

with an area of light ice (1-9%) remaining in the western half of the study areas. Ice percentages and sea

states at each sighting of endangered whales are shown in Appendix B (Table B-1).

Environmental conditions permitted 28 flights during Fall 2000. Of these, only 8 flights were made during

October, primarily due to high sea states and/or low cloud ceilings (Table 2).

B. Survey Effort

The fall field season was from 1 September 2000 through 19 October 2000. Daily totals of kilometers and

hours flown per survey flight during this period are shown in Table 2. A total of 21,053 km of surveys were

flown in 89.89 hours in the study area at an average speed of 234.21 km/hr. The average survey flight was

751.89 km, with over-ocean flight distances ranging from 48 km to 1,394 km. A total of 10,579 km of randomtransect lines were flown in 46.54 hours at an average transect speed of 227.31 km/hr. These random

transects constituted 50.25 percent of the total kilometers flown and 51.77 percent of the total flight hours.

 Survey-flight lines are shown by semimonthly period in Figures 3 through 6.

During the first half of September, survey coverage ranged from 140W. to 157W. longitudes, with most of

the effort within 70 nautical miles (nm) of shore (Fig. 3). There were 19.78 hours of random transects flown

out of 37.72 total flight hours during this period (Table 2), constituting 42.50 percent and 41.96 percent,

respectively, of the total time spent in those effort categories over the fall season.

During the second half of September, most survey coverage ranged from 140W. to 150W. longitudes, within

80 nm of shore (Fig. 4). There were 9.55 hours of random transects flown out of 21.02 total flight hours during

this period (Table 2), constituting 20.52 percent and 23.38 percent, respectively, of the total time spent in

those effort categories.

During the first half of October, survey coverage ranged from 140W. to 154W. longitudes, mostly within 100

nm of shore (Fig. 5). There were 17.01 hours of random transects flown out of 29.03 total flight hours during

this period (Table 2), constituting 36.55 percent and 32.30 percent, respectively, of the total time spent in

those effort categories.

From 16 through 19 October, survey coverage was limited to one flight ranging from 148W. to 154W.

longitudes, within 30 nm of shore (Fig. 6). There were 0.20 hours of random transects flown out of 2.12 total

flight hours during this period (Table 2), constituting 0.43 percent and 2.36 percent, respectively, of the total

time spent in those effort categories.

C. Bowhead Whale (Balaena mysticetus) Observations

1. Sighting Summary: Eighty-nine sightings were made for a total of 193 bowhead whales observed

during Fall-2000 surveys in the study area (Table 3 and Figs. 7-10), not counting definite repeat sightings or

dead whales. Relatively widespread survey coverage between 140W. and 157W. longitudes (Figs. 3-6),

resulted in distribution of bowhead whales all across the study area within 70 nm north of the shoreline

unadjusted for effort (Fig. 10). One of the 193 whales was identified as a calf (Appendix B: Table B-1),

resulting in a seasonal calf ratio (number calves/total whales) of 0.005. A semi-monthly analysis follows.
Table 2

Aerial-Survey Effort in the Beaufort Sea, 1 September–19 October 2000, by Survey Flight

 16

Day

Flight

No.

Transect

(km)

Connect

(km)

Search

(km)

Total

(km)

Transect

(hr)

Total

(hr)

1 Sep 1 767 170 457 1,394 3.27 6.02

2 Sep 2 856 106 430 1,391 3.80 6.23

3 Sep 3 722 116 430 1,268 3.13 5.53

6 Sep 4 0 0 166 166 0.00 0.68

7 Sep 5 0 0 254 254 0.00 0.93

9 Sep 6 0 0 231 231 0.00 1.07

12 Sep 7 574 100 533 1,207 2.63 5.38

13 Sep 8 900 214 170 1,284 3.92 5.68

14 Sep 9 0 0 313 313 0.00 1.15

15 Sep 10 0 0 96 96 0.00 0.38

15 Sep 11 689 203 180 1,073 3.03 4.67

16 Sep 12 0 0 48 48 0.00 0.22

17 Sep 13 514 160 341 1,016 2.35 4.42

18 Sep 14 52 0 228 280 0.22 1.05

20 Sep 15 751 148 435 1,335 3.32 5.72

21 Sep 16 0 0 99 99 0.00 0.37

23 Sep 17 24 0 456 479 0.08 1.82

25 Sep 18 809 221 193 1,224 3.58 5.37

28 Sep 19 0 0 169 169 0.00 0.63

29 Sep 20 0 0 341 341 0.00 1.42

2 Oct 21 76 3 294 373 0.33 1.65

5 Oct 22 134 33 616 782 0.60 3.15

9 Oct 23 741 138 172 1,051 3.25 4.53

10 Oct 24 723 167 280 1,170 3.17 4.95

11 Oct 25 965 85 316 1,365 4.23 5.82

12 Oct 26 698 195 431 1,323 3.05 5.58

13 Oct 27 543 92 138 773 2.38 3.35

17 Oct 28 41 0 506 548 0.20 2.12

Semimonthly Effort Summary

1-15 Sep 4,508 909 3,260 8,677 19.78 37.72

16-30 Sep 2,150 529 2,310 4,991 9.55 21.02

1-15 Oct 3,880 713 2,247 6,837 17.01 29.03

16-19 Oct 41 0 506 548 0.20 2.12

TOTAL 10,579 2,151 8,323 21,053 46.54 89.89
Table 3

Summary of Marine Mammal Sightings, 1 September-19 October 2000, by Survey Flight

(number of sightings/number of animals)

Day

Flight

No.

Bowhead

Whale

Gray

Whale

Beluga

Whale

Unidentified

Cetacean

Bearded

Seal

Ringed

Seal

Pacific

Walrus

Unidentified

Pinniped

1 Sep 1 10/12 0 0 0 6/6 4/4 0 0 2 Sep 2 8/15 1/4 4/8 1/1 0 4/6 0 0 3 Sep 3 11/19 0 5/20 0 5/7 7/10 0 0 6 Sep 4 0 0 0 0 0 0 0 0 7 Sep 5 0 0 0 0 0 0 0 0 9 Sep 6 1/1 0 0 0 0 0 0 0 

12 Sep 7 13/88 0 4/44 0 0 0 0 0 13 Sep 8 1/1 0 1/9 0 2/2 8/77 0 0 14 Sep 9 0 0 0 0 0 0 0 0 15 Sep 10 0 0 0 0 0 0 0 0 15 Sep 11 6/6 0 4/104 0 1/1 30/83 0 0 16 Sep 12 0 0 0 0 0 0 0 0 17 Sep 13 4/4 0 0 0 0 1/1 0 0 18 Sep 14 0 0 0 0 0 0 0 0 20 Sep 15 1/1 0 0 0 10/14 38/57 0 1/6 21 Sep 16 0 0 0 0 0 0 0 0 23 Sep 17 6/6 0 0 0 0 0 0 0 25 Sep 18 5/5 0 2/2 0 1/2 0 0 0 28 Sep 19 0 0 0 0 0 0 0 0 29 Sep 20 0 0 0 0 0 0 0 0 

2 Oct 21 0 0 0 0 0 0 0 0 5 Oct 22 1/2 0 0 0 1/1 0 0 0 9 Oct 23 0 0 4/5 0 0 0 0 0 

10 Oct 24 12/13 0 10/27 0 0 4/5 0 0 11 Oct 25 10/20 0 4/46 0 0 0 0 0 12 Oct 26 0 0 1/1 0 2/2 0 0 0 13 Oct 27 0 0 0 0 0 0 0 0 17 Oct 28 0 0 0 0 0 0 0 0 

17
Table 3

Summary of Marine Mammal Sightings, 1 September-19 October 2000, by Survey Flight

(number of sightings/number of animals)

Day

Flight

No.

Bowhead

Whale

Gray

Whale

Beluga

Whale

Unidentified

Cetacean

Bearded

Seal

Ringed

Seal

Pacific

Walrus

Unidentified

Pinniped

Total Semimonthly Sightings

1-15 Sep 50/142 1/4 18/185 1/1 14/16 53/180 0 0 

16-30 Sep 16/16 0 2/2 0 11/16 39/58 0 1/6 

1-15 Oct 23/35 0 19/79 0 3/3 4/5 0 0 

16-19 Oct 0 0 0 0 0 0 0 0 

TOTAL 89/193 1/4 39/266 1/1 28/35 96/243 0 1/6 

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During the first half of September, 50 sightings were made for a total of 142 bowheads (Table 3), with

sightings ranging between 141W. and 157W. longitudes, based on survey coverage across the study area

(Fig. 3). The first bowheads observed in the Alaskan Beaufort Sea were sighted on 1 September at

7031.8 ́N. latitude, 14703.1 ́W. longitude. Whale pods were evenly distributed east to west, mostly within

60 nm north of the shoreline (Fig. 7). Pod or aggregation sizes ranged from 1 to 47 whales, with a mean of

2.84 (SD=6.78, n=50). No bowhead whale calves were observed during this period (Appendix B: Table B-1).

During the second half of September, 16 sightings were made for a total of 16 bowheads (Table 3), with

sightings between 141W. and 155W. longitudes, based on similar geographic survey coverage (Fig. 4). 

Whale pods were distributed evenly east to west, mostly within 30 nm north of the shoreline (Fig. 8). All pods

were of single whales. No bowhead whale calves were observed during this period (Appendix B: Table B-1).

During the first half of October, 23 sightings were made for a total of 35 bowheads (Table 3), with sightings

clustered between 141W. and 145 ́W. longitudes within 60 nm north of the shoreline as well as between

151W. and 154 ́W. longitudes within 30 nm north of the shoreline (Fig. 9), based on widespread survey

coverage (Fig. 5). Pod sizes ranged from 1 to 5 whales, with a mean of 1.52 (SD=1.04, n=23). One bowhead

whale calf was observed during this period (Appendix B: Table B-1). The last bowhead whales in the Alaskan

Beaufort Sea were sighted on 11 October at 7103.2 ́N. latitude, 15153.3 ́W. longitude.

From 16 through 19 October, no bowhead whales were sighted (Table 3) during one survey flight (Fig. 6).

2. Sighting Rates and Distance from Shore: Maps of raw sighting points like Figure 10 can give a

misleading visual impression when survey effort is unequal. Because survey effort was unequal across our

study area, due primarily to environmental conditions, a graphic method that adjusts for discontinuities in effort

was desired. First, a grid matrix was superimposed across the study area using a Geographic Information

System (ArcView, Version 3.2A). The matrix, consisting of approximately equilateral grid cells sized 5’ latitude

by 15’ longitude, was considered appropriate to the data, simple to query, and visually easy to interpret. 

Bowhead sighting rates were calculated as the number of sightings per kilometer while on northerly-southerly

transect (trSI/km) per individual grid cell. Fall-2000 results, color-coded by calculated sighting rate, are shown

in Figure 11.

In Fall 2000, bowhead sighting rates between Demarcation Point and Flaxman Island, Alaska, were highest

in a horizontal east-west band 15-40 nm from shore (Fig. 11). Other whales between Dease Inlet and Smith

Bay, Alaska, were concentrated very near to the shoreline (see Behaviors section below).

Distances of each bowhead whale sighting from shore in Fall-2000 were measured by ArcView 3.2 as the

distance due north of a normalized shoreline. The mean distance from shore and Standard Deviations for

an East and West Region were calculated (Table 7). West Region bowheads in Fall 2000 (mean = 17.7 km)

were extremely close to shore, such that the southernmost Standard Deviation line was essentially identical

to the normalized shoreline (Fig. 12).

3. Migration Timing: Temporal SPUE was calculated over the entire study area as the number of

sightings made per hour while on search, connect, and transect. These hourly sighting rates (regardless of

survey-effort type), were calculated by survey day during the Fall-2000 bowhead whale migration to identify

any obvious temporal patterns. Of the 89 sightings of bowhead whale pods, the first whale observed was on

1 September. Daily sighting rates were fairly level over the field season, ranging from 0.00 SPUE on 13

separate days up to 3.30 WPUE on 23 September. The last sighting of a bowhead whale was made on 11

October (Table 4).

The WPUE was calculated over the entire study area as the number of individual animals counted per hour

while on search, connect, and transect. This index of relative abundance by survey day was also used to

identify any obvious temporal patterns. Of the 193 individual bowhead whales counted, the data for daily

relative abundance show that the midpoint (median) of the bowhead migration in Blocks 1 through 12 (when

50% of all sighted whales had been recorded) occurred on 12 September. The peak relative abundance

(mode) of 16.36 WPUE also occurred on 12 September (Table 4).
28

Table 4

Number of Sightings and Total Bowhead Whales Observed per Hour,

1 September-19 October 2000, by Flight Day

Day

No. of

Sightings

No. of

Whales

Survey

Time (hr)

Sightings/hr

(SPUE)

Whales/hr

(WPUE)

1 Sep 10 12 6.02 1.66 1.99

2 Sep 8 15 6.23 1.28 2.41

3 Sep 11 19 5.53 1.99 3.44

6 Sep 0 0 0.68 0.00 0.00

7 Sep 0 0 0.93 0.00 0.00

9 Sep 1 1 1.07 0.93 0.93

12 Sep 13 88 5.38 2.42 16.36

13 Sep 1 1 5.68 0.18 0.18

14 Sep 0 0 1.15 0.00 0.00

15 Sep 6 6 5.05 1.19 1.19

16 Sep 0 0 0.22 0.00 0.00

17 Sep 4 4 4.42 0.90 0.90

18 Sep 0 0 1.05 0.00 0.00

20 Sep 1 1 5.72 0.17 0.17

21 Sep 0 0 0.37 0.00 0.00

23 Sep 6 6 1.82 3.30 3.30

25 Sep 5 5 5.37 0.93 0.93

28 Sep 0 0 0.63 0.00 0.00

29 Sep 0 0 1.42 0.00 0.00

2 Oct 0 0 1.65 0.00 0.00

5 Oct 1 2 3.15 0.32 0.63

9 Oct 0 0 4.53 0.00 0.00

10 Oct 12 13 4.95 2.42 2.63

11 Oct 10 20 5.82 1.72 3.44

12 Oct 0 0 5.58 0.00 0.00

13 Oct 0 0 3.35 0.00 0.00

17 Oct 0 0 2.12 0.00 0.00


























  





















	











	












	











	














	





	


	



	 	























 

	





 






	







 

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The most prominent difference in pattern between SPUE and WPUE occurred on 12 September (Table 4),

due to several large pods or aggregations of feeding whales observed on that day (Appendix B: Table B-1).

4. Habitat Associations: In addition to general ice coverage for arctic waters during Fall 2000

(Appendix A), the percentage of ambient ice cover visible from the aircraft at each bowhead sighting

(Appendix B: Table B-1) was summarized. Of the 193 bowheads counted over the field season, 142 whales

(74%) were sighted in open water and 22 (11%) were observed in 1-5% sea ice. When ice cover increased

during October, only small numbers of whales were observed in these higher ice concentrations (Table 5).

 Observing fewer whales in heavy ice concentrations is expected given the reduced counts of bowheads per

unit effort noted for those years of increased general sea-ice severity (Treacy, 1998: Table 13).

5. Behaviors: Of 193 bowhead whales observed during Fall 2000, 80 (41%) were feeding, 78 (40%)

traveling (swimming forward in an apparently deliberate manner), 19 (10%) resting, and 10 (5%) milling when

first sighted. Less frequent behaviors included 3 (2%) that were tail-slapping, 2 (1%) spy-hopping, and 1 (1%)

diving (Table 6). All behaviors noted are defined in Table 1.

Of the 80 feeding bowhead whales observed, 77 were observed on 12 September next to shore between

Dease Inlet and Smith Bay, Alaska, with whales feeding between 15438.5’W. and 15449.7’W. longitudes.

 The high percentage of feeding behaviors in Fall 2000 was likely associated with greater availability of prey

species in this region. Such activity further confirms the importance of the nearshore area east of Barrow as

an occasional feeding area (Landino et al., 1994; Ljungblad et al., 1986). On 11 October, 3 bowhead whales

were observed feeding near 7110.0' N., between 15431.0' W. and 15521.8' W., (Appendix B: Table B-1).

Sudden overt changes (e.g., an abrupt dive, course diversion, or cessation of behavior ongoing) in whale

behavior were looked for. On 10 October 2000, one swimming bowhead was observed from 1490 ft ASL and

a sighting of 2 spy-hopping bowheads was made from 1513 ft ASL for which responses to the survey aircraft

were noted.

D. Other Marine Mammal Observations

1. Gray Whale (Eschrichtius robustus): Over the 2000 season, there was one sighting of 4 gray

whales. These whales were sighted on 2 September just west of Barrow, Alaska (Table 3 and Fig. 13).

2. Beluga Whale (Delphinapterus leucas): Although the study area and survey altitude were

designed to record the fall migration of bowhead whales, beluga whales, which undertake a somewhat parallel

migration farther offshore, were always counted. Over the Fall-2000 field season, 39 sightings were made

for a total of 266 beluga whales (Table 3) during 89.89 hr of overall survey effort (Table 2), for a seasonal

index of relative abundance of 2.96 WPUE. Beluga whales were observed beginning 2 September through

12 October, between 140W. and 155W. longitudes, mostly between 30 and 70 nm from shore (Fig. 14).

 Twenty-nine beluga calves were noted for a calf ratio of 0.109. Forty-six (17%) belugas were in 25% or

greater concentration of ambient sea ice.

3. Bearded Seal (Erignathus barbatus nauticus): Over the 2000 season, 28 incidental sightings

were made for a total of 35 bearded seals (Table 3). All but one bearded seal sighting was made east of

147W. longitude within 40 nm of shore (Fig. 15).

4. Ringed Seal (Pusa hispida hispida): Over the 2000 season, 96 incidental sightings were made

for a total of 243 ringed seals (Table 3). Sightings were made across the study area, mostly within 60 nm of

shore (Fig. 16).

5. Walrus (Odobenus rosmarus divergens): Over the 2000 season, no incidental sightings were

made (Table 3).

6. Unidentified Cetaceans and Pinnipeds: Over the 2000 season, there was 1 incidental sighting for

a total of 6 unidentified pinnipeds and 1 incidental sighting of an unidentified cetacean (Table 3).
32

Table 5

Semimonthly Summary of Bowhead Whales Observed,

by Percent Ice Cover Present at Sighting Location, Fall 2000

% Ice Cover 1-15 Sep 16-30 Sep 1-15 Oct 16-19 Oct Total

0 123 (87%) 9 (56%) 10 (29%) 0 142 (74%)

1-5 16 (11%) 6 (38%) 0 0 22 (11%)

6-10 2 (1%) 1 (6%) 2 (6%) 0 5 (3%)

11-20 0 0 3 (9%) 0 3 (2%)

21-30 1 (1%) 0 4 (11%) 0 5 (2%)

31-40 0 0 0 0 0

41-50 0 0 5 (14%) 0 5 (2%)

51-60 0 0 0 0 0

61-70 0 0 1 (3%) 0 1 (1%)

71-80 0 0 4 (11%) 0 4 (2%)

81-90 0 0 6 (17%) 0 6 (3%)

91-99 0 0 0 0 0

TOTAL 142 (100%) 16 (100%) 35 (100%) 0 (100%) 193 (100%)

Table 6

Semimonthly Summary of Bowhead Whales Observed, by Behavioral Category, Fall 2000

Behavior 1-15 Sep 16-30 Sep 1-15 Oct 16-19 Oct Total

Diving 1 (1%) 0 0 0 1 (1%)

Feeding 77 (54%) 0 3 (9%) 0 80 (41%)

Milling 9 (7%) 1 (6%) 0 0 10 (5%)

Resting 15 (10%) 2 (13%) 2 (6%) 0 19 (10%)

Spy Hopping 0 0 2 (6%) 0 2 (1%)

Swimming 40 (28%) 13 (81%) 25 (71%) 0 78 (40%)

Tail Slapping 0 0 3 (8%) 0 3 (2%)

(not noted) 0 0 0 0 0

TOTAL 142 (100%) 16 (100%) 35 (100%) 0 (100%) 193 (100%)


















































	











	












	











	














	





	


	



	 	























 

	





 






	







 

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37

7. Polar Bear (Ursus maritimus marinus): Over the 2000 season, 9 incidental sightings were made for a

total of 23 polar bears (Table 3). Most of the bears were on barrier islands between 141W. and 150W.

longitudes (Fig. 17). An unknown proportion of these bears appeared to remain on the islands waiting

for the sea ice and may have been recounted on subsequent days. In addition to sightings of polar bears,

28 sets of polar bear tracks were noted for which no bear was present (Table 3 and Fig. 18).




   























                   

                  



  





















	











	












	











	














	





	


	



	 	























 

	





 






	







 

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41

IV. INTERANNUAL RESULTS

A. Statistical Analyses of Bowhead Whale Sighting Distribution (1982-2000)

1. Central Tendency Statistics - Distance from Shore: Transect data were analyzed over a 19-year

period (1982-2000) in two regions of the Alaskan Beaufort Sea (Fig. 2). Annual central-tendency statistics

for distance of bowhead whales from shore were summarized by year and region (Table 7). The mean

distance of whale sightings from shore in each region was also depicted visually for Fall 2000 (Fig. 12).

East Region

The combined data (1982-2000) included 691 transect sightings (trSI) in the East Region. Mean measures

of distance from shore among years ranged from 15.1 km (in 1997) to 89.7 km (in 1983). The Confidence

Interval (CI) about the mean was widest (>30 km) in 1988 and 1989, each of which had a small sample size

(<10 trSI) (Table 7).

West Region

The combined data (1982-2000) included 603 transect sightings in the West Region. Mean measures of

distance from shore ranged from 17.7 km (in 2000) to 65.9 km (in 1988). The Confidence Interval (CI) about

the mean was widest (>30 km) in 1985, 1987, 1990, 1991, and 1994, each of which had a small sample size

(<10 trSI). The axis of the bowhead migration in the West Region was much nearer to shore (median = 11.0

km) during Fall 2000 than for any other year (1982-2000) and much less than the cumulative median for those

years (32.5 km). Likewise, the mean distance from shore for West Region bowheads in 2000 (17.7 km) was

less than for any other year and much less than the cumulative mean for those years (35.4 km) (Table 7).

2. Central Tendency Statistics - Water Depth: The transect data were analyzed over a 19-year

period (1982-2000) in two regions of the Alaskan Beaufort Sea (Fig. 2). Annual central-tendency statistics

for water depth at bowhead whale sightings were summarized by year and region (Table 8).

East Region

The combined data (1982-2000) included 691 transect sightings in the East Region. Annual mean depths

ranged from 23.9 m (in 1997) to 915.5 m (in 1983). The CI about the mean was widest (>100 m) in 1983,

1988, 1989, 1991 and 1994, four of which had a small sample size (<20 trSI). The 25th - 75th quartiles about

the median were widest apart (>35 m) in 1983, 1989, and 1991 (Table 8).

West Region

The combined data (1982-2000) included 603 transect sightings in the West Region. Annual mean depths

ranged from 18.7 m (in 1989) to 312.7 m (in 1983). The CI about the mean was widest (>100 m) in 1982,

1983, 1985, 1986, 1991, 1992, and 1995, four of which had a small sample size (<20 trSI). The 25th-75th

quartiles about the median were widest apart (>35 m) in 1983, 1985, 1986, and 1991. The axis of the

bowhead migration in the West Region was in shallower water (median = 11.3 m) during Fall 2000 than for

any previous year (1982-1999) (Table 8).

3. ANOVA - Distance from Shore: A parametric ANOVA of distances from shore over a 19-year

period (1982-2000) indicated strongly significant differences among years for the East Region (F=19.7 (18, 691);

p<0.0001) and for the West Region (F=10.6 (18, 603); p<0.0001). A preliminary power analysis of the ANOVA

(=0.05, 0.01), comparing only those years from 1982 through1997 having a larger sample size (n20 trSI),

showed minimum detectable differences of 7.8 km in the East Region and 9.7 km in the West (Treacy, 1998).

4. Tukey HSD Test - Distance from Shore: Since the ANOVA showed significant differences among

years, the Tukey HSD test was applied to all transect sightings of bowhead whales over a 19-year period

(1982-2000) without exclusions to determine which years were significantly different from each other.

East Region

The Tukey test showed that bowheads in 1983 migrated significantly (p<0.05) farther offshore than in any

other year except 1989. The data also showed that whales in 1989 were significantly farther offshore, and

in 1997, and 1998 were significantly nearer to shore, than for most (>9) other years.
Table 7

Central-Tendency Statistics for Distance from Shore (in kilometers) to Random Sightings

of Bowhead Whales (September-October), by Year and Region, 1982-2000

42

Year Region trSI 1

Median

25th-75th

Quartile

Range

Mean SD

2

CI

3 Range

1982 East 28 36.9 31.5-43.2 38.2 8.5 34.9-41.5 26.0-56.6

West 26 41.7 37.7-48.9 43.7 16.7 36.9-50.4 14.6-86.3

1983 East 14 89.5 82.0-98.9 89.7 15.7 80.7-98.8 59.6-121.2

West 15 53.3 42.3-86.6 62.2 26.3 47.6-76.7 27.5-125.3

1984 East 23 36.6 25.6-56.5 39.7 23.9 29.3-50.0 1.9-103.4

West 36 46.2 36.8-60.3 45.7 19.2 39.2-52.2 8.9-85.2

1985 East 10 29.5 23.7-40.5 31.8 16.0 20.4-43.3 1.9-61.4

West 7 50.3 25.9-86.3 53.8 29.2 26.8-80.8 15.4-88.9

1986 East 30 27.5 16.7-39.8 27.8 16.7 21.5-34.0 1.0-58.1

West 19 38.8 24.7-52.4 39.9 22.8 28.9-50.9 3.7-81.7

1987 East 30 33.5 18.5-50.1 37.0 20.7 29.3-44.7 6.9-86.1

West 8 29.2 16.7-51.2 32.7 20.2 15.9-49.6 7.4-60.3

1988 East 6 29.5 24.4-33.9 33.4 23.5 8.8-58.0 6.4-76.8

West 8 64.5 59.1-71.4 65.9 11.2 56.6-75.3 50.7-86.8

1989 East 6 55.8 49.3-89.4 63.4 23.4 38.8-87.9 36.1-94.0

West 17 35.4 15.6-45.8 32.8 19.4 22.8-42.8 7.5-74.5

1990 East 93 33.8 25.4-43.0 34.5 13.8 31.7-37.4 8.1-78.6

West 6 35.8 32.3-48.2 42.5 18.5 23.1-61.9 25.9-77.3

1991 East 14 62.4 39.4-76.7 59.2 20.5 47.4-71.1 34.5-85.6

West 6 46.0 34.1-72.3 51.5 18.8 31.7-71.2 33.6-76.8

1992 East 12 38.2 34.3-51.6 42.5 10.9 35.6-49.4 28.5-60.5

West 13 61.1 45.1-74.3 59.3 17.2 48.9-69.7 29.9-82.2

1993 East 55 30.3 21.2-40.4 31.9 17.0 27.3-36.5 6.4-88.4

West 35 25.1 20.4-38.6 29.9 12.7 25.6-34.3 11.8-62.7

1994 East 32 29.4 22.4-56.2 37.2 18.7 30.4-44.0 13.9-77.7

West 3 23.3 4 24.8 11.5 4 14.1-36.9
Table 7

Central-Tendency Statistics for Distance from Shore (in kilometers) to Random Sightings

of Bowhead Whales (September-October), by Year and Region, 1982-2000

43

Year Region trSI 1

Median

25th-75th

Quartile

Range

Mean SD

2

CI

3 Range

1995 East 94 30.2 23.6-41.6 33.1 16.4 29.7-36.5 3.7-99.5

West 44 36.5 25.3-51.7 42.9 26.5 34.8-50.9 7.6-118.7

1996 East 13 29.4 21.0-34.6 29.1 11.4 22.2-36.0 15.3-57.6

West 15 40.6 23.6-55.1 40.8 14.8 32.6-49.1 21.4-64.1

1997 East 35 10.2 5.9-20.4 15.1 11.9 11.0-19.1 3.4-44.9

West 145 27.4 20.0-36.3 29.2 13.0 27.1-31.3 1.0-66.0

1998 East 103 22.2 13.6-31.3 23.8 13.0 21.3-26.3 4.0-73.8

West 113 20.9 14.7-32.5 26.3 18.6 22.8-29.8 1.1-124.0

1999 East 68 40.2 28.5-49.7 39.5 13.5 36.3-42.8 -0.15-65.8

West 68 36.1 27.0-52.1 39.3 17.5 35.1-43.6 9.2-75.6

2000 East 26 39.3 28.7-52.1 43.5 22.7 34.3-52.7 13.9-108.8

West 19 11.0 4.7-25.3 17.7 19.2 8.5-27.0 0.02-80.8

Cumulative East 691 32.0 20.9-43.6 34.5 19.4 33.0-35.9 -0.15-121.2

(1982-2000) West 603 32.5 20.2-47.1 35.4 20.5 33.8-37.1 0.02-125.3

1

 trSI = number of transect sightings.

2

 SD = standard deviation.

3

 CI  95-percent confidence interval (positive values). 4

 Insufficient sample size.

5

 Negative value is for one transect sighting between the actual and normalized coastline.
Table 8

Central-Tendency Statistics for Water Depth (in meters) at Random Sightings

of Bowhead Whales (September-October), by Year and Region, 1982-2000

44

Year Region trSI 1

Median

25th-75th

Quartile

Range

Mean SD

2

CI

3 Range

1982 East 28 42.1 38.6-49.0 43.5 6.4 41.0-46.0 34.9-57.3

West 26 30.3 22.8-37.4 94.0 210.9 8.9-179.2 14.3-1041.5

1983 East 14 804.0 263-1779 915.5 718.8 501-1331 64.6-1952.8

West 15 68.3 33.7-209.1 312.7 597.9 18.4-643.9 20.7-2165.7

1984 East 23 43.9 35.2-54.3 77.0 104.8 31.7-122.3 17.8-507.9

West 36 40.3 31.7-55.6 47.7 33.2 36.5-59.0 12.8-189.2

1985 East 10 38.3 34.8-40.8 37.5 7.4 32.3-42.8 22.8-51.0

West 7 35.7 23.9-148.1 193.3 348.5 129-515.6 16.1-974.7

1986 East 30 41.1 24.0-50.2 38.1 18.2 31.4-44.9 6.8-91.5

West 19 28.3 18.9-75.1 77.9 117.4 21.3-134.6 9.6-489.7

1987 East 30 39.7 32.7-54.3 56.3 47.9 38.4-74.2 14.9-223.3

West 8 25.2 13.1-31.6 22.6 10.0 14.2-30.9 8.3-32.4

1988 East 6 48.8 39.1-50.3 92.2 123.5 37.3-221.8 22.9-343.4

West 8 49.4 46.9-52.7 50.3 6.8 44.6-55.9 40.5-63.5

1989 East 6 60.5 51.1-448.4 196.1 219.7 34.5-426.7 47.3-508.8

West 17 20.1 11.3-24.1 18.7 8.1 14.5-22.8 5.8-33.8

1990 East 93 42.0 35.9-50.1 47.7 33.0 40.9-54.5 19.6-284.6

West 6 31.5 22.8-39.2 32.6 11.4 20.6-44.6 20.0-50.6

1991 East 14 68.7 50.5-190.7 128.3 109.6 65.0-191.6 46.3-387.0

West 6 41.5 35.5-204.8 96.6 94.2 2.2-195.5 26.3-230.2

1992 East 12 53.5 47.1-56.0 51.5 6.0 47.7-55.3 40.5-58.9

West 13 50.8 43.9-53.6 54.1 27.8 37.3-70.8 14.3-121.3

1993 East 55 40.5 33.5-50.2 58.4 96.5 32.3-84.5 11.4-716.6

West 35 20.1 16.4-25.4 22.8 9.4 19.6-26.0 10.7-49.3

1994 East 32 46.8 39.0-53.3 79.8 175.6 16.5-143.1 30.7-1037.8

West 3 12.0 4 21.4 16.6 4 11.6-40.5
Table 8

Central-Tendency Statistics for Water Depth (in meters) at Random Sightings

of Bowhead Whales (September-October), by Year and Region, 1982-2000

45

Year Region trSI 1

Median

25th-75th

Quartile

Range

Mean SD

2

CI

3 Range

1995 East 94 41.4 35.7-49.9 52.5 68.7 38.4-66.6 14.9-628.0

West 44 30.8 25.8-38.8 107.4 259.7 28.4-186.4 6.5-1232.8

1996 East 13 39.4 33.4-45.6 37.7 9.3 32.1-43.3 15.0-48.5

West 15 34.8 23.6-44.3 37.0 17.1 27.5-46.5 18.6-82.5

1997 East 35 22.1 13.0-32.0 23.9 11.9 19.8-28.0 10.5-50.0

West 145 20.0 15.7-26.5 25.0 21.4 21.5-28.5 4.7-189.2

1998 East 103 32.4 26.1-40.3 34.2 12.0 31.9-36.6 6.6-82.6

West 113 15.2 11.6-21.5 37.7 170.8 5.9-69.6 5.4-1814.7

1999 East 68 50.2 39.5-54.6 51.2 20.9 46.2-56.3 7.9-171.3

West 68 30.7 21.1-41.9 42.6 42.9 32.2-53.0 10.9-210.3

2000 East 26 40.6 36.3-56.9 81.6 122.0 32.3-130.9 28.4-108.8

West 19 11.3 6.8-19.6 31.5 81.5 7.8-70.8 4.0-366.8

Cumulative East 691 40.7 33.5-50.6 70.5 172.3 57.6-83.4 6.6-1952.8

(1982-2000) West 603 23.9 15.8-36.0 52.4 159.1 39.7-65.1 4.0-2165.7

1

 trSI = number of transect sightings.

2

 SD = standard deviation.

3

 CI  95-percent confidence interval (positive values). 4

 Insufficient sample size.
47

West Region

The Tukey test showed that bowheads in 2000 migrated significantly (p<0.05) nearer to shore than for most

(>9) other years.

B. General Sea Ice Severity (1979-2000)

General ice coverage along the northern coast of Alaska during the 2000 navigation season was the 28thmildest for the 48 years from 1953 through 2000 and showed a distance of 75 nm from Point Barrow

northward to the boundary of 5-tenths ice concentration on 15 September (USDOC, NOAA, National Ice

Center/USDOD, Navy, Naval Ice Center, 2001).

The years 1980, 1983, 1988, and 1991 were categorized as having “heavy” ice cover during the navigation

season. These 4 years are ranked as having the severest seasonal ice for the years 1979 through 2000 and

showed distances ranging from 10 to 25 nm between Point Barrow and the five-tenths ice concentration on

15 September (USDOC, NOAA, National Ice Center/USDOD, Navy, Naval Ice Center, 2001).

The years 1984, 1985, and 1992, categorized as having “moderate” ice cover during the open-water season,

are ranked next in seasonal ice severity for the years 1979 through 2000 and showed distances ranging from

50 to 75 nm between Point Barrow and the five-tenths ice concentration on 15 September (USDOC, NOAA,

National Ice Center/USDOD, Navy, Naval Ice Center, 2001).

The years 1979, 1981, 1982, 1986, 1987, 1989, 1990, and 1993-2000, categorized as having “light” ice cover

during the open-water season, are ranked as having the least-severe seasonal ice for the years 1979 through

2000 and showed distances ranging from 50 to 240 nm between Point Barrow and the five-tenths ice

concentration on 15 September (USDOC, NOAA, National Ice Center/USDOD, Navy, Naval Ice Center, 2001).

 The recent eight years of unbroken light ice coverage (1993-2000) based on these criteria were not

inconsistent with recently hypothesized global and/or cyclical warming.

C. General Sea Ice Severity and Bowhead Whale Sighting Rates (1982-2000)

The Geographic Information System (ArcView, Version 3.2A) was used to depict bowhead whales sighting

rates during their fall migration across the Alaskan Beaufort Sea relative to overall sea-ice severity. 

Cumulative sightings made on northerly-southerly transects for September-October MMS surveys over a 19-

year period (1982-2000) were calculated as sighting rates then mapped per individual grid cell as was done

for Figure 11 (see Section III.C.2). Selected ETOPO-5 isobaths were also included for visual reference

(Treacy, 2001).

Sighting location data were pooled over years with light ice (1982, 1986-87, 1989-90, 1993-2000), moderate

ice (1984-85, 1992), and heavy ice (1983, 1988, 1991) as defined in MMS survey reports (Treacy, 2000),

based on a severity index for the North Coast of Alaska (USDOC, NOAA, National Ice Center/USDOD, Navy,

Naval Ice Center, 2001). Thirteen of the 19 years (1982-2000) were in light ice years. The total number of

bowhead whales observable per hour of survey flight (1979-1997) was much higher for light ice years (2.96

WPUE) than for moderate ice years (1.55 WPUE) or heavy ice years (0.46 WPUE) (Treacy, 1998).

Visual inspection of a gridded map of sighting rates of bowhead whales by previously described ice severity

(Figs. 19-22) showed substantial overlap east of Kaktovik, Alaska, and west of Dease Inlet, Alaska, with more

distinct differences for the central Alaskan Beaufort Sea (142W. to 155W. longitudes). During light-ice

years, the highest sighting rates of central-area bowhead whales were generally in shallower, near-shore

waters reflecting coastal contours. During moderate-ice years, area whales occurred in mid-range waters,

albeit with some overlap of both light- and heavy-ice categories. During heavy-ice years, area whales

occupied deeper, offshore waters, with little overlap of whale sighting rates for light-ice years. The relationship

between distance from shore and sea-ice severity appears to be more geographically restricted than

previously noted (Moore, 2000; Treacy, 2000).

A preliminary analysis using the parametric ANOVA of cumulative distances of bowhead sightings from a


























  





















	











	












	











	














	






	



	



	 	
























 

	





 






	







 

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normalized shoreline in heavy, moderate, and light sea-ice categories over a 19-year period (1982-2000)

indicated significant differences (F=143.8 (2, 1294); p<0.0001). Post-hoc testing using both the Scheffe Test and

Tukey HSD test for unequal sample sizes (StatisticaTM StatSoft, Version 5.1) indicated significant differences

(p<0.0001) between the distances of bowhead whale sightings from a normalized shoreline under each pair

of sea-ice conditions.

These ice-severity categories were reflected in the mean distances of bowhead whales from the normalized

shoreline in the central Alaskan Beaufort Sea. Mean distances for the heavy ice years (1983, 1988, 1991)

ranged from 61.5 km to 80.1 km. Mean distances for the moderate ice years (1984, 1985, 1992) ranged from

46.3 km to 51.4 km. Mean distances for the light ice years (1982, 1986, 19897, 1989, 1990, 1993-2000)

ranged from 23.9 km to 42.1 km.

D. Key Results Summary (1979-2000)

 General sea ice severity north of Alaska during the 2000 navigation season was the 28th mildest for the 48-

year period from 1953 through 2000 (USDOC, NOAA, National Ice Center/USDOD, Navy, Naval Ice

Center, 2001). Sea ice was heavier in the east bathymetric region.

 Environmental conditions permitted 28 flights during Fall 2000. Of these, only 8 flights were made during

October, primarily due to high sea states and/or low cloud ceilings.

 Due to adverse environmental conditions, the annual total of 89.89 survey hours for 2000 was the third

lowest for the MMS surveys (1987-2000), considerably lower than the mean of 130.63 hours (SD=36.47,

n=13) for previous years (1987-1999).

 Also due to adverse environmental conditions, the 89 sightings for a total of 193 individual bowhead whales

in Fall 2000 ranked 10th for the 14 MMS project surveys (1987-2000), lower than the 417 annual mean

for whales in previous MMS surveys (1987-1999) (SD=455, n=13).

 A high percentage of bowheads were feeding (41%) when observed in Fall 2000. Of these, 77 (96%) of

the total 80 feeding bowheads were only observed on 12 September very near shore between Dease Inlet

and Smith Bay, Alaska (between 15438.5' W. and 15449.3' W.), further confirming the importance of

this area as an occasional feeding area.

 In 2000, the first bowheads observed were on 1 September. Sighting rates were highest on 12 September

(2.42 SPUE), 23 September (3.30 SPUE), and 10 October (2.42 SPUE). The data on daily relative

abundance (WPUE) showed that the peak (mode) of the bowhead migration occurred on 12 September

(16.36 WPUE), corresponding with the large feeding aggregations noted on that day. The midpoint

(median) of the total whales observed (n=193) also occurred on 12 September. The last sighting of a

bowhead in 2000 was made on 11 October.

 The axis of bowhead whale sightings in the West Region was much nearer to shore (median = 11.0 km)

during Fall 2000 than for any other year (1982-2000) as well as much less than the cumulative median

for those years (32.5 km). Likewise, the mean distance from shore for West Region bowheads in 2000

(17.7 km) was less than for any other year as well as much less than the cumulative mean for those years

(35.4 km). The Tukey test confirmed that bowheads in 2000 migrated significantly (p<0.05) nearer to

shore than for most (>9) other years.

 Bowhead whales occur farther offshore in heavy-ice years during fall migrations across the Central Alaskan

Beaufort Sea (142W. to 155W. longitudes). Bowheads generally occupy nearshore waters in years of

light sea-ice severity, somewhat more offshore waters in moderate ice years, and are even farther

offshore in heavy ice years. While factors other than sea ice may have localized effects on site-specific

distributions, broad-area distributions of bowhead whale sightings in the central Alaskan Beaufort Sea are

related to overall sea-ice severity.
54

 An ANOVA of cumulative distances of bowhead whale sightings from a normalized shoreline in heavy,

moderate, and light sea-ice categories over a 19-year period (1982-2000) indicated significant differences

(F=143.8 (2, 1294); p<0.0001). Post-hoc testing using both the Scheffe Test and Tukey HSD test for unequal

sample sizes indicated significant differences (p<0.0001) between the distances of bowhead whale

sightings from a normalized shoreline under each pair of sea-ice conditions.

 Other results of the present study were generally within the range of result values from previous MMSfunded endangered-whale monitoring conducted during September and October (1979-1999) in the

Beaufort Sea using similar survey methods (Ljungblad et al., 1987; Moore and Clarke, 1992; Treacy,

1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, and 2000).
55

V. DISCUSSION

A. Management Use of Real-Time Field Information

The MMS issues various types of permits to industry for gas and oil exploration, including vessel geophysical

permits for on-water exploration using an array of deep-seismic airguns; vessel geological-geophysical permits

for shallow-seismic exploration using an airgun; on-ice geophysical permits using VIBROSEIS technology;

both vessel and on-ice geological permits for obtaining core samples; and permits to drill for gas and oil.

During winter-spring of 1999-2000, two over-ice seismic programs proposed for the offshore Beaufort Sea

area were canceled because of thick ice conditions and difficulties in implementing regulatory restrictions

relative to ringed seals. During the open-water season, Western Geophysical conducted seismic-vessel

exploration from 28 July to 31 August, with no seismic exploration during September and October. In general,

to prevent potential operational effects on subsistence whaling, any geophysical-vessel explorations permitted

during the fall follow stringent restrictions—including a provision to stop seismic operations when whales are

visible from the vessel—as the bowhead whale migration progresses through the area of operations. For any

explorations that occur during the fall, daily summaries of survey information are transferred from the field to

Anchorage for use by MMS Resource Evaluation and by NMFS in implementing area-wide permit restrictions

on high-energy seismic operations during the whale migration.

During Spring 2000, the gravel island and pipeline associated with the Northstar Unit were completed. During

the open-water season, pre-fabricated facilities and a drill-rig were transported and installed at Northstar. 

There were no drilling operations, with associated helicopter and vessel support, in the Beaufort Sea in Fall

2000. In general, during any fall drilling operations, daily summaries of field information from this survey, and

other arctic surveys being conducted concurrently, are transferred by the MMS Team Leader to MMS Field

Operations in Anchorage. The MMS and NMFS review daily reports to determine the distributional patterns

of bowheads in the vicinity of oil-and-gas-industry activities and the timing of the bowhead whale migration,

especially the “end of the migration” past any drill sites.

The sighting data are typically used by management groups to monitor the progress of the overall fall

migration of bowhead whales across the Alaskan Beaufort Sea and to determine the position of their overall

migratory corridor relative to shore. Project ice and weather data were also transmitted daily to the

National/Naval Ice Center and National Weather Service for use in ground-truthing satellite imagery.

B. Management Use of Interannual Monitoring

The MMS bowhead whale monitoring began in 1979 and has continued every year up to the present. While

some aspects of this study have been updated from time to time, the data recorded have remained

remarkably parallel (especially data from 1982-2000), thus permitting many one-to-one comparisons between

years. Such continuous, long-term, wide-area, aerial monitoring of a large whale migration is indeed unique.

In addition to the use of real-time information by both MMS and NMFS when documenting the progress of

endangered bowhead whales past offshore drilling and seismic exploration operations (see Section VI.A.

above), the project has been helpful to managers in other ways. Some notable examples are:

 providing raw data to all parties (MMS, Western Geophysical, NMFS, ARCO Alaska, Inc., and Alaska

Eskimo Whaling Commission (AEWC) at an Oil/Whalers Agreement Post Season Meeting on 18

December 1990 to determine whether the Fall 1990 bowhead migration had been temporarily blocked due

to seismic exploration activities;

 providing all parties with annual reports from which data were subsequently cited in a declaration to a

lawsuit in 1993 (AEWC et al. vs. Dr. Nancy Foster et al., Civil Action No. 93-1629 HHG) on the effects of

Kuvlum drilling and seismic exploration operations on the bowhead migration corridor;

 providing upstream, offshore, and downstream sighting-and-effort data in order to enhance sample sizes

of many site-specific studies looking at the potential effects of oil-industry activity on bowhead whale

migrations;
56

 documenting geographic areas, especially migration corridors and feeding areas, used annually by

bowhead whales. Such data from previous surveys continue to be used by MMS in writing Environmental

Impact Statements and Environmental Assessments and in interpreting the results of site-specific studies.

 performing an analysis of the distances from shore to bowhead sightings relative to general sea ice

severity.

The BWASP was cited in the MMS Annual Report 1999, “What does it take to best manage America’s mineral

resources?”, as an example of how our agency manages the OCS in the Beaufort Sea;

The NMFS Administrator, Alaska Region, (letter dated 22 December 1998) commended MMS information

support to NMFS: “The BWASP has provided a critical element in our ability to evaluate the effects of

development in the Beaufort Sea on the bowhead whale. Additionally, the Minerals Management Service has

demonstrated the flexibility and willingness to allow this program to compliment and extend project-specific

monitoring required for authorizations under the Marine Mammal Protection Act (Incidental Harassment

Authorizations). The combined information of these efforts has greatly extended our knowledge and facilitated

conflict avoidance agreements. These agreements have allowed oil and gas activities to go forward while

minimizing interference with traditional Native subsistence hunting. We have found BWASP statistical

analysis and data presentation to be very useful in assessing potential impacts within the Beaufort Sea.”

C. Conclusions

We saw no indications that the migration was “stopped” in Fall 2000, including areas near the Northstar

production site.

Oil-industry studies, pooling our data with their own site-specific data, have detected localized deflections on

the order of 10 to 20 km by bowhead whales in the immediate vicinity of certain types of active seismic

exploration (USDOI, MMS, 1997b). Since preliminary power analysis of the ANOVA for distance of bowhead

whales from shore (=0.05, 0.01) showed minimum detectable differences of 7.8 km in the East Region

and 9.7 km in the West (Treacy, 1998), we should be able to detect any region-wide 10- to 20-km shifts

between years that may have derived from localized deflections.

Bowhead whales occur farther offshore in heavy-ice years during fall migrations across the Central Alaskan

Beaufort Sea (142W. to 155W. longitudes). Bowheads generally occupy nearshore waters in years of light

sea-ice severity, somewhat more offshore waters in moderate ice years, and are even farther offshore in

heavy ice years. While other factors (other than sea ice) may have localized effects on site-specific

distributions, broad-area distributions of bowhead whale sightings in the central Alaskan Beaufort Sea are

related to overall sea-ice severity. Both Kaktovik and Nuiqsut communities conduct subsistence whale hunts

each year in the central Alaskan Beaufort Sea, where the distance offshore to conduct this important

subsistence activity can be crucial to their safety and hunting success. To the extent villagers from Barrow

utilize the area east of 155W. longitude to hunt whales, distances from shore to the main migration corridor

would likewise be negatively affected in heavier ice years.

D. Field Coordination and Other Information Support

During the field season, we coordinated with AEWC, Barrow, Alaska; Whalers Communication Center,

Deadhorse, Alaska; NMFS, Anchorage, Alaska; and NSB, Department of Wildlife Management, Barrow,

Alaska.

Selected BWASP information-support activities during calendar year 2000 included:

 providing whale distribution data in support of site-specific/acoustic monitoring of marine mammals near

the Northstar pre-production facility;

 presenting a paper, “Fall 1997 Migration of Bowhead Whales Across the Alaskan Beaufort Sea as Noted

by the MMS Bowhead Whale Aerial Survey Project with Preliminary Fall 1998-99 Survey Results” (In MMS

Alaska Region Beaufort Sea Information Update Meeting, OCS Study MMS 2000-023), in Barrow, Alaska,

on 28 March 2000 (http://www.mms.gov/omm/alaska/ess);
57

 participating in annual interagency evaluations (with NMFS, NSB, AEWC) on BP Exploration (Alaska)’s and

WesternGeco’s site-specific planned and reported monitoring of marine mammals near seismic and

Northstar pre-production operations on 23-24 May 2000 at the National Marine Mammal Laboratory

(NMML);

 presenting project information at a Workshop on the Design of Studies Needed for the Evaluation of

Cumulative Impacts of Oil and Gas Exploration and Production on Fall Migrating Bowhead Whales and

the Fall Bowhead Whale Subsistence Hunt” , held 6-7 November 2000 at NMML;

 providing data to and coordinating with scientists and subsistence whalers in support of the MMS study

“Bowhead Whale Feeding in the Eastern Alaskan Beaufort Sea: Update of Scientific and Traditional

Information”;

 providing maps of bowhead whale distribution to the MMS Regional Director in support of a Briefing Book

for Lease Sale 176;

 providing BWASP maps Mr. Michael Baffrey, USDOI;

 providing a set of previous BWASP reports to Ms. Jan Philips, North Slope Borough, and to Dr. Stephen

R. Braund and Associates, Anchorage, Alaska.
59

VI. LITERATURE CITED

Aagaard, K. 1984. The Beaufort Undercurrent. In: The Alaskan Beaufort Sea: Ecosystems and Environment.

 P.W. Barnes, D.M. Schell, and E. Reimnitz (eds.). Academic Press., pp. 47-71.

Brower, W.A., R.G. Baldwin, C.N. Williams, J.L. Wise, and L.D. Leslie. 1988. Climatic Atlas of the Outer

Continental Shelf Waters and Coastal Regions of Alaska, Volume III. OCS Study MMS 87-0013. USDOI,

MMS, Alaska OCS Region, 524 pp.

Chapman, C.F. 1971. Piloting, Seamanship and Small Boat Handling. New York, NY: Hearst Books, 640

pp.

Cochran, W.G. 1963. Sampling Techniques. New York, NY: J. Wiley, 413 pp.

Endangered Species Act of 1973, as amended. 16 USC 1531-1543.

Houghton, J.P., D.A. Segar, and J.E. Zeh. 1984. Beaufort Sea Monitoring Program. In: Proceedings of a

Workshop (September 1983) and Sampling Design Recommendations. Prepared by Dames and Moore,

Seattle, WA, for the OCS Environmental Assessment Program, Juneau, AK, 111 pp.

Johnson, M.A., A.Y. Proshutinsky, and I.V. Polakov. 1999. Atmospheric Patterns Forcing Two Regimes of

Arctic Circulation: A Return to Anticyclonic Conditions? Geophys. Res. Lett 26: 1621-1624.

LaBelle, J.C., J.L. Wise, R.P. Voelker, R.H. Schulze, and G.M. Wohl. 1983. Alaska Marine Ice Atlas. Arctic

Environmental Information and Data Center, University of Alaska, Anchorage, AK, 302 pp.

Landino, S.W., S.D. Treacy, S.A. Zerwick, and J.B. Dunlap. 1994. A Large Aggregation of Bowhead Whales

(Balaena mysticetus) Feeding near Point Barrow, Alaska, in Late October 1992. Arctic 47 (3): 232-235.

LGL Ecological Research Associates, Inc. 1987. Importance of the Eastern Alaskan Beaufort Sea to Feeding

Bowhead Whales, 1985-86, W.J. Richardson, ed. OCS Study MMS 87-0037. Prepared for USDOI, MMS,

Alaska OCS Region.

Ljungblad, D.K., S.E. Moore, and J.T. Clarke. 1986. Assessment of Bowhead Whale (Balaena mysticetus)

Feeding Patterns in the Alaskan Beaufort and Northeastern Chukchi Seas via Aerial Surveys, Fall 1979-84.

 Rep. Int. Whal. Commn. 36 (SC/37/PS1): 265-272.

Ljungblad, D.K., S.E. Moore, J.T. Clarke, and J.C. Bennett. 1987. Distribution, Abundance, Behavior and

Bioacoustics of Endangered Whales in the Alaskan Beaufort and Eastern Chukchi Seas, 1979-86. OCS

Study MMS 87-0039. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 391 pp.

Marine Mammal Protection Act of 1972. 16 USC 1361-1407.

Moore, S.E. 2000. Variability of Cetacean Distribution and Habitat Selection in the Alaskan Arctic, Autumn

1982-91. Arctic 53 (4): 448-460.

Moore, S.E. and J.T. Clarke. 1992. Distribution, Abundance and Behavior of Endangered Whales in the

Alaskan Chukchi and Western Beaufort Seas, 1991: With a Review 1982-91. OCS Study MMS 92-0029.

 Anchorage, AK: USDOI, MMS, Alaska OCS Region, 211 pp.

Moore, S.E. and D.P. DeMaster. 1997. Cetacean Habitats in the Alaskan Arctic. J. NW Atlantic Fish. Sci.

22: 55-69.

National Environmental Policy Act of 1969. 42 USC 4321-4347.
60

Norton, D. and G. Weller. 1984. The Beaufort Sea: Background, History, and Perspective. In: The Alaskan

Beaufort Sea, P. Barnes, D. Schell, and E. Reimnitz, eds. Orlando, FL: Academic Press, Inc., 466 pp.

Outer Continental Shelf Lands Act of 1953, as amended in 1978. 43 USC 1331-1356 and 1801-1866.

Proshutinsky and Johnson. 1997. Two Circulation Regimes of the Wind-driven Arctic Ocean. Journal of

Geophysical Research 102(C6):12493-12514.

Rice, D.W. 1998. Marine Mammals of the World: Systematics and Distribution. Special Publication Number

4. The Society for Marine Mammalogy. 231 pp.

Treacy, S.D. 1988. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1987. OCS Study MMS

88-0030. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 141 pp.

Treacy, S.D. 1989. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1988. OCS Study MMS

89-0033. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 101 pp.

Treacy, S.D. 1990. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1989. OCS Study MMS

90-0047. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 104 pp.

Treacy, S.D. 1991. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1990. OCS Study MMS

91-0055. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 107 pp.

Treacy, S.D. 1992. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1991. OCS Study MMS

92-0017. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 92 pp.

Treacy, S.D. 1993. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1992. OCS Study MMS

93-0023. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 135 pp.

Treacy, S.D. 1994. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1993. OCS Study MMS

94-0032. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 132 pp.

Treacy, S.D. 1995. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1994. OCS Study MMS

95-0033. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 116 pp.

Treacy, S.D. 1996. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1995. OCS Study MMS

96-0006. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 120 pp.

Treacy, S.D. 1997. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1996. OCS Study MMS

97-0016. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 115 pp.

Treacy, S.D. 1998. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1997. OCS Study MMS

98-0059. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 143 pp.

Treacy, S.D. 2000. Aerial Surveys of Endangered Whales in the Beaufort Sea, Fall 1998-1999. OCS Study

MMS 2000-066. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 135 pp.

Treacy, S.D. 2001. Bowhead Whales (Balaena mysticetus) Occur Farther Offshore in Heavy-Ice Years

during Fall Migrations across the Central Alaskan Beaufort Sea. Abstract In: 14th Biennial Conference on

the Biology of Marine Mammals, Abstracts (28 Nov. – 3 Dec 2001; Vancouver B.C. Canada). p. 217.

USDOC, NOAA, NMFS. 1982. Endangered Species Act, Section 7 Consultation - Biological Opinion, Oil and

Gas Lease Sale 71 (Diapir Field). 19 May 1982. Washington, D.C.

USDOC, NOAA, NMFS. 1983. Endangered Species Act, Section 7 Consultation - Biological Opinion, Oil and

Gas Leasing and Exploration-Diapir Field Lease Offering (Sale 87). 19 December 1983. Washington, D.C.
61

USDOC, NOAA, NMFS. 1987. Endangered Species Act, Section 7 Consultation - Biological Opinion, Oil and

Gas Leasing and Exploration - Beaufort Sea Sale 97. 20 May 1987. Washington, D.C.

USDOC, NOAA, NMFS. 1988. Endangered Species Act, Section 7 Consultation - Biological Opinion, Oil and

Gas Leasing and Exploration - Arctic Region. 23 November 1988. Washington, D.C.

USDOC, NOAA, National Ice Center/USDOD, Navy, Naval Ice Center. 2001. Seasonal Outlook, Sea Ice

Conditions for the Alaskan North Coast, Summer 2001. Washington, D.C., 5 pp.

USDOD, Navy, Naval Hydrographic Office. 1956. Aerial Ice Reconnaissance and Functional Glossary of Ice

Terminology. Hydrographic Office Publication No. 609, 14 pp.

USDOI, MMS. 1979. State of Alaska, Department of Natural Resources; Federal/State Joint Beaufort Sea

Oil and Gas Lease Sale BF, November 7, 1979 (44 FR 64752).

USDOI, MMS. 1982. Memorandum from Director, BLM, to Secretary of the Interior, dated 30 April 1982;

subject: Decision on the Modification of the Seasonal Drilling Restriction.

USDOI, MMS. 1984. Outer Continental Shelf, Diapir Field, Oil and Gas Lease Sale 87, July 23, 1984 (49 FR

29726).

USDOI, MMS. 1988. Outer Continental Shelf, Beaufort Sea, Oil and Gas Lease Sale 97, February 12, 1988

(53 FR 4356).

USDOI, MMS. 1991. Outer Continental Shelf Beaufort Sea Oil and Gas Lease Sale 124, May 24, 1991 (56

FR 23966).

USDOI, MMS. 1996. Outer Continental Shelf Beaufort Sea Oil and Gas Lease Sale 144, August 16, 1996

(61 FR 42682).

USDOI, MMS. 1997. Arctic Seismic Synthesis and Mitigating measures Workshop. OCS Study MMS 97-

0014. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 71 pp. plus appendices.

USDOI, MMS. 1998. Alaska Outer Continental Shelf, Beaufort Sea Planning Area Oil and Gas Lease Sale

170 OCS EIS/EA MMS 98-0007.

USDOI, MMS. 2000. Project Management Plan, MMS Fall 2000 Bowhead Whale Aerial Survey Project,

August 1998. Anchorage, AK: USDOI, MMS, Alaska OCS Region, 14 pp.

Zar, S.H. 1984. Biostatistical Analysis. Englewood Cliffs, NJ: Prentice Hall, Inc., 620 pp.
63

APPENDIX A

FALL 2000 ICE CONCENTRATION MAPS FOR THE BEAUFORT SEA


























  





















	











	












	











	














	





	


	



	 	























 

	





 






	







 

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72
73

APPENDIX B

FALL 2000 BOWHEAD WHALE SIGHTING DATA
Table B-1

Selected Sighting Data for Bowhead Whales Observed, Fall 2000

 75

Flight

No. Day

Total

Whales

No. of

Calves Latitude Longitude Behavior

Compass

Heading

Ice

(%)

Wind

Force

1 1 Sep 3 0 7031.8' 14703.1' swim 130 1 3

1 1 Sep 1 0 7032.5' 14654.5' swim 330 1 3

1 1 Sep 1 0 7032.7' 14643.8' swim 230 1 3

1 1 Sep 1 0 7033.1' 14632.7' rest 250 1 3

1 1 Sep 1 0 7034.0' 14630.7' swim 120 1 3

1 1 Sep 1 0 7033.8' 14356.1' rest 180 0 O

1 1 Sep 1 0 7024.2' 14156.1' rest 160 0 1

1 1 Sep 1 0 7022.9' 14212.3' rest 90 30 1

1 1 Sep 1 0 7018.5' 14452.1' swim 50 0 1

1 1 Sep 1 0 7027.0' 14614.4' dive 250 1 2

2 2 Sep 2 0 7057.9' 15123.1' swim 70 1 4

2 2 Sep 7 0 7110.0' 15439.8' mill 1 0 3

2 2 Sep 1 0 7111.1' 15439.0' swim 180 0 3

2 2 Sep 1 0 7118.2' 15507.7' swim 170 0 3

2 2 Sep 1 0 7122.4' 15540.2' swim 80 0 3

2 2 Sep 1 0 7116.9' 15549.5' rest 130 0 4

2 2 Sep 1 0 7117.8' 15512.6' swim 290 0 2

2 2 Sep 1 0 7200.7' 15435.9' swim 340 0 2

3 3 Sep 1 0 7023.6' 14430.0' swim 240 0 1

3 3 Sep 1 0 7024.7' 14404.6' swim 240 0 1

3 3 Sep 2 0 7008.6' 14143.3' swim 60 1 1

3 3 Sep 1 0 7010.3' 14142.7' swim 30 1 1

3 3 Sep 2 0 7021.4' 14210.0' mill 1 10 1

3 3 Sep 2 0 7012.3' 14211.1' rest 180 0 1

3 3 Sep 2 0 7021.3' 14451.9' rest 250 0 1

3 3 Sep 4 0 7026.5' 14451.2' rest 50 0 1

3 3 Sep 2 0 7025.0' 14450.8' swim 250 0 1

3 3 Sep 1 0 7027.7' 14518.8' swim 60 1 1

3 3 Sep 1 0 7022.5' 14518.2' rest 240 1 1

6 9 Sep 1 0 7033.7' 14707.6' swim 270 0 2

7 12 Sep 9 0 7108.6' 15448.2' feed 1 0 4

7 12 Sep 1 0 7112.3' 15517.9' swim 240 0 4

7 12 Sep 3 0 7112.3' 15518.4' swim 340 0 4

7 12 Sep 1 0 7112.7' 15520.4' swim 1 0 4

7 12 Sep 1 0 7134.5' 15605.5' swim 240 0 4

7 12 Sep 1 0 7111.2' 15514.9' swim 190 0 4

7 12 Sep 1 0 7112.2' 15514.9' swim 220 0 4

7 12 Sep 1 0 7121.8' 15513.7' swim 10 0 4

7 12 Sep 1 0 7145.4' 15433.4' dead4 1 0 6

7 12 Sep 1 0 7108.1' 15449.3' swim 230 0 4

7 12 Sep 11 0 7107.4' 15449.7' feed 1 0 4

7 12 Sep 47 0 7104.8' 15443.4' feed 1 0 4
Table B-1

Selected Sighting Data for Bowhead Whales Observed, Fall 2000

 76

Flight

No. Day

Total

Whales

No. of

Calves Latitude Longitude Behavior

Compass

Heading

Ice

(%)

Wind

Force

7 12 Sep 10 0 7103.0' 15438.5' feed 1 0 4

7 12 Sep 1 0 7056.2' 15408.7' swim 180 0 2

8 13 Sep 1 0 7016.4' 14421.7' swim 300 0 2

11 15 Sep 1 0 7049.4' 15058.6' swim 290 0 4

11 15 Sep 1 0 7055.1' 15352.7' rest 290 0 2

11 15 Sep 1 0 7055.5' 15352.9' swim 150 0 2

11 15 Sep 1 0 7133.2' 15221.6' swim 40 0 3

11 15 Sep 1 0 7058.4' 15134.7' swim 240 0 6

11 15 Sep 1 0 7042.4' 14917.4' swim 240 1 3

13 17 Sep 1 0 7017.7' 14121.8' swim 220 1 4

13 17 Sep 1 0 6957.3' 14219.8' swim 90 10 3

13 17 Sep 1 0 7012.0' 14242.9' swim 290 1 5

13 17 Sep 1 0 7017.7' 14545.7' swim 210 1 4

15 20 Sep 1 0 7029.6' 14707.7' swim 290 1 5

17 23 Sep 1 0 7112.8' 15256.7' swim 220 0 5

17 23 Sep 1 0 7120.4' 15425.2' mill 1 0 5

17 23 Sep 1 0 7110.0' 15448.5' rest 310 0 6

17 23 Sep 1 0 7108.6' 15444.6' swim 310 0 6

17 23 Sep 1 0 7043.2' 15124.2' swim 180 0 5

17 23 Sep 1 0 7042.1' 15118.8' swim 300 0 5

18 25 Sep 1 0 7047.6' 14847.3' swim 270 0 3

18 25 Sep 1 0 7040.6' 14746.8' swim 270 0 2

18 25 Sep 1 0 7021.7' 14604.1' rest 1 0 3

18 25 Sep 1 0 7025.9' 14556.0' swim 160 1 2

18 25 Sep 1 0 7024.8' 14516.4' swim 230 1 3

22 5 Oct 2 0 7016.8' 14340.7' rest 150 0 3

24 10 Oct 1 0 7026.0' 14448.9' swim 260 30 2

24 10 Oct 1 0 7026.0' 14448.9' swim 260 30 2

24 10 Oct 1 0 7026.0' 14448.9' swim 360 30 2

24 10 Oct 1 0 7024.5' 14430.2' swim 260 0 2

24 10 Oct 1 0 7024.3' 14424.2' swim 260 0 2

24 10 Oct 1 0 7015.2' 14335.9' swim 250 30 2

24 10 Oct 1 0 7015.8' 14312.4' swim 270 65 2

24 10 Oct 1 0 7022.8' 14422.8' swim 245 50 2

24 10 Oct 1 0 7031.7' 14422.7' swim 60 85 2

24 10 Oct 1 0 7057.4' 14451.2' swim 180 10 4

24 10 Oct 1 0 7051.3' 14448.8' swim 180 10 5

24 10 Oct 2 0 7032.1' 14442.3' spy hop 270 90 2

25 11 Oct 1 0 7100.1' 15248.9' swim 270 50 2

25 11 Oct 1 0 7100.3' 15309.8' swim 270 50 2

25 11 Oct 1 0 7101.5' 15314.5' swim 210 50 2

25 11 Oct 1 0 7102.0' 15316.7' swim 200 50 2
Table B-1

Selected Sighting Data for Bowhead Whales Observed, Fall 2000

 77

Flight

No. Day

Total

Whales

No. of

Calves Latitude Longitude Behavior

Compass

Heading

Ice

(%)

Wind

Force

25 11 Oct 3 0 7100.7' 15332.0' swim 190 90 2

25 11 Oct 1 0 7102.5' 15344.8' swim 200 80 2

25 11 Oct 1 0 7108.1' 15305.6' swim 285 0 4

25 11 Oct 3 0 7104.2' 15210.1' feed 210 80 2

25 11 Oct 3 0 7103.0' 15209.0' tail slap 360 20 2

25 11 Oct 5 1 7103.2' 15153.3' swim 230 0 4

1

 Not recorded.

2

 Possible repeat sighting.

3

 Definite repeat sighting (excluded from analyses).

4

 Dead whale (excluded from analyses).
79

APPENDIX C

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109

APPENDIX D

GLOSSARY OF ABBREVIATIONS, ACRONYMS, AND INITIALISMS
111

GLOSSARY OF ABBREVIATIONS, ACRONYMS, AND INITIALISMS

AEWC Alaska Eskimo Whaling Commission

ANOVA analysis of variance

BLM Bureau of Land Management

BWASP Bowhead Whale Aerial Survey Project

CI confidence interval

e.g. for example

ESA Endangered Species Act

FR Federal Register

GPS Global Positioning System

hr hour

HSD “honestly significant difference” (Tukey statistical test)

i.e. that is

k number of samples

km kilometer

m meter

MMS Minerals Management Service

n sample size

NOAA National Oceanic and Atmospheric Administration

NOS Notice of Sale

NMFS National Marine Fisheries Service

nm nautical mile

NSB North Slope Borough

OAS Office of Aircraft Services

OCS Outer Continental Shelf

OCSLA Outer Continental Shelf Lands Act

p probability

SD standard deviation

SPUE sightings per unit effort; sighting rate

trSI transect sightings

USC U.S. Code

USDOC U.S. Department of Commerce

USDOD U.S. Department of Defense

USDOI U.S. Department of the Interior

WPUE whales per unit effort; relative abundance
The Department of the Interior Mission

As the Nation's principal conservation agency, the Department of the Interior has responsibility for

most of our nationally owned public lands and natural resources. This includes fostering sound use

of our land and water resources; protecting our fish, wildlife, and biological diversity; preserving the

environmental and cultural values of our national parks and historical places; and providing for the

enjoyment of life through outdoor recreation. The Department assesses our energy and mineral

resources and works to ensure that their development is in the best interests of all our people by

encouraging stewardship and citizen participation in their care. The Department also has a major

responsibility for American Indian reservation communities and for people who live in island

territories under U.S. administration.

The Minerals Management Service Mission

As a bureau of the Department of the Interior, the Minerals Management Service's (MMS) primary

responsibilities are to manage the mineral resources located on the Nation's Outer Continental

Shelf (OCS), collect revenue from the Federal OCS and onshore Federal and Indian lands, and

distribute those revenues.

Moreover, in working to meet its responsibilities, the Offshore Minerals Management Program

administers the OCS competitive leasing program and oversees the safe and environmentally

sound exploration and production of our Nation's offshore natural gas, oil and other mineral

resources. The MMS Royalty Management Program meets its responsibilities by ensuring the

efficient, timely and accurate collection and disbursement of revenue from mineral leasing and

production due to Indian tribes and allottees, States and the U.S. Treasury.

The MMS strives to fulfill its responsibilities through the general guiding principles of: (1) being

responsive to the public's concerns and interests by maintaining a dialogue with all potentially

affected parties and (2) carrying out its programs with an emphasis on working to enhance the

quality of life for all Americans by lending MMS assistance and expertise to economic development

and environmental protection.