U.S. Department of Commerce | National Oceanic and Atmospheric Administration | National Marine Fisheries Service

Endangered Species Act Recovery Plan for the Southern Distinct Population 

Segment of Eulachon (Thaleichthys pacificus)

Prepared by: National Marine Fisheries Service, West Coast Region

 
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Recovery Plan for

Southern Distinct Population Segment of

Eulachon

Thaleichthys pacificus
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Disclaimer

Endangered Species Act (ESA) recovery plans delineate such reasonable actions as may be 

necessary, based upon the best available scientific and commercial data available, for the 

conservation and survival of listed species. Plans are published by the National Marine Fisheries 

Service (NMFS). Recovery plans do not necessarily represent the views, official positions, or 

approval of any individuals or agencies involved in the plan formulation, other than NMFS. They 

represent the official position of NMFS only after they have been signed by the Assistant 

Administrator. ESA recovery plans are guidance and planning documents only; identification of 

an action to be implemented by any public or private party does not create a legal obligation 

beyond existing legal requirements. Nothing in this plan should be construed as a commitment or 

requirement that any Federal agency obligate or pay funds in any one fiscal year in excess of 

appropriations made by Congress for that fiscal year in contravention of the Anti-Deficiency Act, 

31 U.S.C. 1341, or any other law or regulation. Approved recovery plans are subject to 

modification as dictated by new information, changes in species status, and the completion of 

recovery actions. 

LITERATURE CITATION SHOULD READ AS FOLLOWS: 

National Marine Fisheries Service. September 2017. Recovery Plan for the Southern Distinct 

Population Segment of Eulachon (Thaleichthys pacificus). National Marine Fisheries Service, 

West Coast Region, Protected Resources Division, Portland, OR, 97232.

ADDITIONAL COPIES MAY BE OBTAINED FROM: 

National Marine Fisheries Service 

1201 NE Lloyd Blvd., Suite 1100

Portland, OR 97232

Phone: 503.230.5400

Recovery plans can also be downloaded from the NMFS website:

http://www.nmfs.wcr.gov

Photo Credit: Copyright: Michele Cornelius, www.123rf.com/profile_mscornelius
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Acknowledgements

Eulachon Recovery Team

The National Marine Fisheries Service gratefully acknowledges the contributions of the 

Eulachon Recovery Team, and thanks them for generously contributing their time and expertise 

in the development of this Recovery Plan.

The National Marine Fisheries Service expresses its solemn gratitude to the late Dr. Robert 

(Bob) Emmett for his contributions to this Recovery Plan.

Robert Anderson – National Marine Fisheries Service, West Coast Region

Dr. Rick Gustafson – National Marine Fisheries Service, Northwest Fisheries Science Center

Dr. Jeff Hard – National Marine Fisheries Service, Northwest Fisheries Science Center

Olaf Langness – Washington Department of Fish and Wildlife

Dr. Steve Munch – National Marine Fisheries Service, Southwest Fisheries Science Center

Dr. Tom Wainwright – National Marine Fisheries Service (retired), Northwest Fisheries Science 

Center

Eulachon Stakeholder Group

The National Marine Fisheries Service also acknowledges the contributions of the Eulachon 

Stakeholder Group for their time and contributions to this Recovery Plan: Taylor Aalvik, Cowlitz 

Indian Tribe; John Barco, Bonneville Power Administration; Michael Belchik, Yurok Indian 

Tribe; Dave Bingaman, Quinault Indian Tribe; Jeff Breckel, Lower Columbia Fish Recovery 

Board; Bobby Brunoe, Warm Springs Indian Tribe; Joyce Casey, U.S. Army Corps of Engineers;

Heather Brekke, Department of Oceans and Fisheries Canada; Cindy LeFleur, Washington 

Department of Fish and Wildlife; Mike McHenry, Elwha Indian Tribe; Lynn Palensky, 

Northwest Power and Conservation Council; Brad Pettinger, Oregon Trawl Commission; Kevin 

Shaffer, California Department of Fish and Wildlife; Tom Rien, Oregon Department of Fish and 

Wildlife; and Paul Ward, Confederation Tribes and Bands of the Yakama Nation. 

Recovery Plan Author

Robert Anderson – National Marine Fisheries Service, West Coast Region, Protected Resources 

Division 
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Recovery Plan Development

This recovery plan is the product of a collaborative process initiated by NMFS and strengthened 

through regional and local participation. The goal was to produce a Recovery Plan that would 

meet NMFS’ ESA requirements for recovery plans as well as broader needs. Throughout the 

recovery planning process, NMFS collaborated with the states of California, Oregon, and 

Washington, the Department of Fisheries and Oceans Canada, as well as with other Federal 

agencies, tribal and local governments, representatives of industry and environmental groups, 

other stakeholders, and the public. 

The collaborative process reflects NMFS’ belief that ESA recovery plans should be based on 

state, regional, tribal, local, and private conservation efforts already underway throughout the 

region. Local support of recovery plans by those whose activities directly affect the listed 

species, and whose actions will be most affected by recovery efforts, is essential to recovery plan 

implementation. 

NMFS developed this Recovery Plan by synthesizing the best available scientific and 

commercial data available with input from (1) the Eulachon Recovery Team, and (2) the 

Eulachon Stakeholder Group. On October 20, 2016, we released the Proposed ESA Recovery 

Plan for the southern DPS of Eulachon (Draft Recovery Plan), and published a notice of 

availability in the Federal Register (81 FR 72572) requesting comments. Four comment 

submissions were received during the 60-day public comments period on the Draft Recovery 

Plan. We considered all of the public comments received on the Draft Recovery Plan in 

developing the final version of the Recovery Plan.
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Table of Contents

Disclaimer ..................................................................................................................................................5

Acknowledgements...................................................................................................................................6

Eulachon Recovery Team...........................................................................................................................6

Eulachon Stakeholder Group.....................................................................................................................6

Recovery Plan Author................................................................................................................................6

Recovery Plan Development......................................................................................................................7

List of Tables...........................................................................................................................................11

List of Figures .........................................................................................................................................13

Abbreviations and Acronyms................................................................................................................14

Terms and Definitions ...........................................................................................................................15

EULACHON RECOVERY PLAN—EXECUTIVE SUMMARY....................................................................18

Introduction.............................................................................................................................................18

Current Status of the DPS ........................................................................................................................18

Abundance and Productivity ...................................................................................................................18

Threats and Limiting Factors ...................................................................................................................19

Eulachon Recovery—what does recovery look like, and how will we know when we are there? .........20

Recovery Strategy ..................................................................................................................................22

Priority Actions ........................................................................................................................................22

Near-Term Research Priorities ................................................................................................................23

Recovery Goal, Objectives, and Delisting Criteria ...............................................................................24

Recovery Goal.........................................................................................................................................24

Recovery Objectives...............................................................................................................................25

Delisting Criteria ....................................................................................................................................26

Adaptive Management...........................................................................................................................27

Time and Cost Estimates .......................................................................................................................28

Chapter 1. Introduction: Biology and Life History of Eulachon .............................................................29

Overview:.................................................................................................................................................29

A. Species Description.........................................................................................................................29

B. Distribution .....................................................................................................................................31

C. Morphology.....................................................................................................................................34

D. Genetic Differentiation ...................................................................................................................35
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E. Body Composition...........................................................................................................................38

F. Age, Growth, and Maturation.........................................................................................................40

G. Sex Ratio..........................................................................................................................................43

H. Spawning.........................................................................................................................................46

Chapter 2. Listing Factors........................................................................................................................51

1. Threats Assessment ........................................................................................................................51

A. Present or Threatened Destruction, Modification, or Curtailment of Habitat or Range ....................53

B. Over-utilization for Commercial, Recreational, Scientific, or Educational Purposes ..........................71

C. Disease or Predation............................................................................................................................79

D. Inadequacy of Existing Regulatory Mechanisms.................................................................................82

E. Other Natural or Manmade Factors Affecting its Continued Existence ..............................................83

2. Conservation Actions......................................................................................................................99

Fisheries Regulations.............................................................................................................................101

Chapter 3. Recovery Goals, Objectives, and Delisting Criteria ............................................................101

A. Recovery Goal...................................................................................................................................102

B. Recovery Objectives and Delisting Criteria ...................................................................................102

Recovery Objectives.............................................................................................................................105

Delisting Criteria ..................................................................................................................................105

Chapter 4. Recovery Strategy..............................................................................................................107

Primary Focus and Justification of Recovery Strategy......................................................................107

Chapter 5. Recovery Program .............................................................................................................108

Recovery Actions..................................................................................................................................108

ACTION 1: Establish a Eulachon Technical Recovery and Implementation Team .........................108

ACTION 2: Implement Outreach and Education Strategies ..............................................................108

ACTION 3: Near-Term Research Priorities ........................................................................................108

ACTION 4: Conserve Spatial Structure and Temporal Distribution.................................................110

ACTION 5: Eliminate or Sufficiently Reduce the Severity of Threats...............................................110

Marine Habitats....................................................................................................................................110

Bycatch..................................................................................................................................................110

Predation ..............................................................................................................................................111

Dams/Water Diversions ......................................................................................................................111

ACTION 6: Assess Regulatory Measures—Inadequacy of Existing Regulatory Mechanisms ........115
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ACTION 7: Develop a Research, Monitoring, Evaluation, and Adaptive Management Plan...........115

Implementation Schedule and Costs.....................................................................................................117

Anticipated Date of Recovery................................................................................................................118

Total Cost of Recovery...........................................................................................................................118

Table 5-1. Recovery Actions and Cost Estimates...................................................................................119

Literature Cited......................................................................................................................................129
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List of Tables

Table ES-1. Eulachon Level of Threat Severity in each Subpopulation.

Table 2-1. Eulachon qualitative threats rankings by subpopulation, and ESA Section 

4(a)(1)(b) Factors. 

Table 2-2. Eulachon Level of Threat Severity in each Subpopulation.

Table 2-3. Annual Columbia River eulachon run size 2000-2017.

Table 2-4. Annual Fraser River eulachon run size 1995-2017. 

Table 2-5. Numbers and weight of eulachon observed and bycatch ratios from ocean shrimp 

trawl vessels that landed their catch in Washington (2010–2015). Bycatch ratios 

were calculated for each year by dividing the observed catch of eulachon (in 

numbers of eulachon and in kg of eulachon) by the observed weight (in mt) of 

retained ocean shrimp. A fleet-wide bycatch estimate (in both weight and number 

of fish) was obtained by multiplying the bycatch ratios by fleet-wide ocean 

shrimp landings. 95% bootstrapped confidence intervals (CI) are provided for the 

estimates. Asterisks (*) signify strata with fewer than three observed vessels.

Table 2-6. Numbers and weight of eulachon observed and bycatch ratios from ocean shrimp 

trawl vessels that landed their catch in Oregon (2010–2015). Bycatch ratios were 

calculated for each year by dividing the observed catch of eulachon (in numbers 

of eulachon and in kg of eulachon) by the observed weight (in mt) of retained 

ocean shrimp. A fleet-wide bycatch estimate (in both weight and number of fish) 

was obtained by multiplying the bycatch ratios by fleet-wide ocean shrimp 

landings. 95% bootstrapped confidence intervals (CI) are provided for the 

estimates. Asterisks (*) signify strata with fewer than three observed vessels.

Table 2-7. Numbers and weight of eulachon observed and bycatch ratios from ocean shrimp 

trawl vessels that landed their catch in California (2010–2015). Bycatch ratios 

were calculated for each year by dividing the observed catch of eulachon (in 

numbers of eulachon and in kg of eulachon) by the observed weight (in mt) of 

retained ocean shrimp. A fleet-wide bycatch estimate (in both weight and number 

of fish) was obtained by multiplying the bycatch ratios by fleet-wide ocean 

shrimp landings. 95% bootstrapped confidence intervals (CI) are provided for the 

estimates. Asterisks (*) signify strata with fewer than three observed vessels.
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Table 2-8. Total estimated bycatch of eulachon (number of individuals and mt) in ocean 

shrimp fisheries observed by the West Coast Groundfish Observer Program from 

2004-2015. Ocean shrimp fisheries were not observed in 2006.

Table 2-9. Estimated bycatch of eulachon (number of individual fish) in U.S. west coast 

groundfish fisheries that were observed by the West Coast Groundfish Observer 

Program (WCGOP) and the At-Sea Hake Observer Program (A- SHOP) from 

2002–2015.

Table 5-1. Recovery Actions and Cost Estimates.
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List of Figures

Figure ES-1. Recovery strategy conceptual model.

Figure ES-2. The adaptive management process.

Figure 1-1. Distribution of eulachon spawning rivers (open circles) in the Northeast Pacific 

Ocean.

Figure 2-1. A working hypothesis on how changes in the Pacific Decadal Oscillation affect 

productivity in the northern California Current.

Figure 2-2. Number of eulachon caught in the Columbia River and Tributary commercial 

fishery, 1888-2017.

Figure 2-3. Annual Columbia River eulachon run size, harvest, and exploitation rate 

estimates, 2000- 2017.

Figure 2-4. Landings data for the commercial fishery on the Fraser River for the years, 1881 

through 2004.

Figure 2-5. Landings data for the BC coastal subpopulation, 1877-2009.

Figure 2-6. Commercial landings in ocean shrimp trawl fisheries off the U.S. west coast 

through 2016.

Figure 2-7. Percent length frequency of eulachon captured in ocean shrimp trawl nets with 

and without 1–4 LED lights attached in the vicinity of the bycatch reduction 

device and with and without 10 LED lights attached to the trawl fishing line.

Figure 2-8. Haul-by-haul comparison of the catch of eulachon (kg) in the two nets of a 

double-rigged shrimp trawl vessel with one side incorporating 10 LED lights on 

the fishing line and the other acting as a control. The ratio of control/treatment 

catch is also shown (solid line). Label “P” or “S” denotes the side of trawl gear 

(port or starboard) used as the control net.

Figure 3-1. Recovery strategy conceptual model.

Figure 5-1. The adaptive management process.
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Abbreviations and Acronyms

Biological Review Team BRT

Department of Fisheries and Oceans Canada DFO

Distinct Population Segments DPS

Environmental Species Act ESA

National Oceanic and Atmospheric Administration NOAA

Northwest Fisheries Science Center NWFSC

National Marine Fisheries Service NMFS

Oregon Department of Fish and Wildlife ODFW

United States Fish and Wildlife Service USFWS

Washington Department of Fish and Wildlife WDFW
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Terms and Definitions

Adaptive Management The process of adjusting management actions and/or directions 

based on new information.

Endangered Species A species in danger of extinction throughout all or a significant 

portion of its range.

ESA Recovery Plan A plan to recover a species listed as threatened or endangered 

under the U.S. Endangered Species Act (ESA). The ESA requires 

that recovery plans, to the extent practicable, incorporate (1) 

objective, measurable criteria that, when met, would result in a 

determination that the species is no longer threatened or 

endangered; (2) site-specific management actions that may be 

necessary to achieve the plan's goals; and (3) estimates of the time 

required and costs to implement recovery actions.

Delisting Criteria Criteria incorporated into ESA recovery plans that define both 

biological viability (biological criteria) and alleviation of the 

causes for decline (threats criteria based on the five listing factors 

in ESA section 4[a][1]), and that, when met, would result in a 

determination that a species is no longer threatened or endangered 

and can be proposed for removal from the Federal list of 

threatened and endangered species.

Diversity All the genetic and phenotypic (life history, behavioral, and 

morphological) variation within a population. Variations could 

include fecundity, run timing, spawn timing, behavior, age at 

maturity, egg size, developmental rate, ocean distribution patterns, 

male and female spawning behavior, physiology, molecular 

genetic characteristics, etc.

Escapement The amount of fish in a given population that does not get caught 

by commercial or recreational fisheries and return to their 

freshwater spawning habitat.

Factors for Decline Five general categories of causes for decline of a species, listed in 

the Endangered Species Act section 4(a)(1)(b): (A) the present or 

threatened destruction, modification, or curtailment of its habitat or 

range; (B) overutilization for commercial, recreational, scientific, 

or educational purposes; (C) disease or predation; (D) the 
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inadequacy of existing regulatory mechanisms; or (E) other natural 

or human-made factors affecting its continued existence.

Goal The end toward which effort is directed.

Limiting Factors Impaired physical, biological, or chemical features (e.g., 

inadequate spawning habitat, high water temperature, insufficient 

prey resources) that result in reductions in population parameters 

(abundance, productivity, spatial structure, and diversity). Key 

limiting factors are those with the greatest impacts on a 

population’s (or major population group’s or species’) ability to 

reach its desired status.

Monitoring Implementation monitoring to determine whether an activity was 

performed and/or completed as planned.

Objectives The parameters which, when taken together, characterize the 

conditions under Persistence Probability

Persistence Probability The complement of a population’s extinction risk (i.e., persistence 

probability = 1 – extinction risk).

Phenotypic Trait A phenotypic trait is an obvious, observable, and measurable trait; 

it is the expression of genes in an observable way.

Productivity The average number of surviving offspring per parent. Productivity 

is used as an indicator of a population’s ability to sustain itself or 

its ability to rebound from low numbers. The terms “population 

growth rate” and “population productivity” are interchangeable 

when referring to measures of population production over an entire 

life cycle. 

Recovery Strategy A statement that identifies the assumptions and logic—the 

rationale—for the species’ recovery program.

Self-sustaining A self-sustaining viable population has a negligible risk of 

extinction due to reasonably foreseeable changes in circumstances 

affecting its abundance, productivity, spatial structure, and 

diversity characteristics over a 100- year period and achieves these 

characteristics without dependence upon artificial propagation. 

Artificial propagation may be used to benefit threatened and 

endangered species and a self-sustaining population may include 

artificially propagated fish, but a self-sustaining population must 

not be dependent upon propagation measures to achieve its viable 
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characteristics. Artificial propagation may contribute to but is not a 

substitute for addressing the underlying factors (threats) causing or 

contributing to a species’ decline.

Threatened Species A species likely to become endangered within the foreseeable 

future throughout all or a significant portion of its range.

Threats Human activities or natural events (e.g., dams, road building, 

floodplain development, fish harvest, hatchery influences, and 

volcanoes) that cause or contribute to limiting factors. Threats may 

exist in the present or be likely to occur in the future.
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EULACHON RECOVERY PLAN—EXECUTIVE SUMMARY

Introduction

This Recovery Plan serves as a blueprint for the protection and recovery of the southern Distinct

Population Segment (DPS) of eulachon (Thaleichthys pacificus) using the best available science 

per the requirements of the Endangered Species Act (ESA). The Recovery Plan links threats and 

management actions to an active research program to fill data gaps, and a monitoring program to 

assess these actions’ effectiveness. Research and monitoring results will provide information to 

refine ongoing actions and prioritize new actions to achieve the Plan’s goal: to restore the listed 

species to the point where it no longer requires the protections of the ESA.

Current Status of the DPS

Eulachon are endemic to the northeastern Pacific Ocean; they range from northern California to 

southwest and south-central Alaska and into the southeastern Bering Sea. The southern DPS of 

eulachon is comprised of fish that spawn in rivers south of the Nass River in British Columbia to, 

and including, the Mad River in California (Gustafson et al. 2010), and was listed as a threatened 

species1under the ESA on March 18, 2010 (75 FR 13012). NMFS’ 2016 ESA five-year review 

concluded that the DPS’s threatened designation remained appropriate. Critical habitat was 

designated under the ESA for eulachon on October 20, 2011 (76 FR 65324). 

The Biological Review Team (BRT) concluded that, starting in 1994, the southern DPS of 

eulachon experienced an abrupt decline in abundance throughout its range (Gustafson et al.

2010). Although eulachon abundance in monitored rivers improved in the 2013–2015 return 

years, recent conditions in the northeast Pacific Ocean are likely linked to the sharp declines in 

eulachon abundance in monitored rivers in 2016 and 2017. The likelihood that these poor ocean

conditions will persist into the near future suggest that subpopulation declines may again be 

widespread in the upcoming return years. 

Abundance and Productivity

There are no reliable fishery-independent, historical abundance estimates for eulachon.

Spawning stock biomass estimations of eulachon in the Columbia River for the years 2000 

through 2017 have ranged from a low of 783,400 fish in 2005 to a high of 185,965,200 fish in 

2013, with an estimated 18,307,100 fish in 20172. Spawning stock biomass estimations of 

eulachon in the Fraser River for the years 1995 through 2017 have ranged from a low of 109,129 

 

1

In this document, “the species” and “eulachon” refers to the southern DPS of eulachon.

2 Annual Columbia River eulachon run size 2000-2017; pounds converted to numbers of fish at 11.16 fish/pound 

(WDFW 2017). The estimates were calculated based on methods developed by Parker (1985), Jackson and Cheng 

(2001), and Hay et al. (2002) to estimate spawning biomass of pelagic fishes. For 2000 through 2010 estimates were 

back-calculated using historical larval density data.
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to 146,606 fish in 2010 to a high of 41,709,035 to 56,033,332 fish in 1996, with an estimated 

763,330 to 1,026,251 fish in 20173. 

Threats and Limiting Factors 

The BRT categorized climate change impacts on ocean conditions as the most serious threat to 

the persistence of eulachon in all four subpopulations of the DPS: Klamath River, Columbia 

River, Fraser River, and British Columbia coastal rivers south of the Nass River. Climate change 

impacts on freshwater habitat and eulachon bycatch in offshore shrimp fisheries were also 

ranked in the top four threats in all subpopulations of the DPS. Dams and water diversions in the 

Klamath and Columbia rivers and predation in the Fraser and British Columbia coastal rivers 

filled out the last of the top four threats (Gustafson et al. 2010). These threats, together with large 

declines in abundance, indicated to the BRT that eulachon were at moderate risk of extinction 

throughout all of its range (Gustafson et al. 2010). Table ES-1 is the BRT’s qualitative threats 

assessment based on the modal score for each threat in each subpopulation. The BRT did not 

identify any limiting factors for eulachon. 

Table ES-1. Eulachon Level of Threat Severity in each Subpopulation.

Subpopulation

Threats Klamath Columbia Fraser BC

Severity

Climate change impacts on ocean conditions high high high high

Dams /water diversions moderate moderate very low very low

Eulachon bycatch moderate high moderate high

Climate change impacts on freshwater habitat moderate moderate moderate moderate

Predation moderate moderate moderate moderate

Water quality moderate moderate moderate low

Catastrophic events very low low very low low

Disease very low very low very low very low

Competition low low low low

Shoreline construction very low moderate moderate low

Tribal/First Nations fisheries very low very low very low low

Non-indigenous species very low very low very low very low

Recreational harvest very low low very low very low

Commercial harvest very low low low very low

Scientific monitoring very low very low very low very low

Dredging very low moderate low very low

 

3

 The estimates were calculated based on methods developed by (Parker 1985), Jackson and Cheng (2001), and Hay 

et al. (2002) to estimate spawning biomass of pelagic fishes. Spawning stock biomass estimates for the Fraser River 

subpopulation were based on 9.9 fish/pound and 13.3 fish/pound, respectively. 
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Eulachon Recovery—what does recovery look like, and how will we know when we 

are there?

There is more that is not known about eulachon (e.g., their distribution and abundance in the 

marine environment, or how the species responds to condition-shifts in the marine and 

freshwater environments), than is known. These uncertainties present a challenge in developing 

quantifiable parameters (e.g., abundance—numbers of spawners averaged over a time period 

sufficient to account for year-to-year fluctuations that are due to natural environmental variation)

that would indicate when eulachon are viable, self-sufficient, and no longer in danger of 

extinction or likely to become endangered in the foreseeable future. Therefore, what is provided 

here is a recovery concept which describes a set of qualitative conditions that if met, would 

indicate that the species is likely no longer in danger of extinction. 

What we don’t know—historically, eulachon have been a relatively poorly monitored 

species—compared to other commercial and recreational fisheries. As such, the data necessary to 

develop quantitative-based (e.g., life-cycle models, population viability analysis) recovery 

criteria for abundance and productivity does not exist. Likewise, the data to develop genetic, life 

history, and spatial diversity criteria for eulachon is too fragmented to develop subpopulationspecific recovery criteria. As such, and at this time, this Recovery Plan does not provide 

quantitative viability criteria for each biological parameter—abundance, productivity, spatial 

structure and temporal distribution, and genetic and life history diversity—for each 

subpopulation, but instead provides general recovery criteria based on the limited data we have 

and the principals of conservation biology. 

What we do know—the historical accounts of eulachon portray a species with sustained 

runs sufficient to provide a century-plus of unrestrained harvest opportunities throughout the 

range of the species. 

The historical landings data for the Columbia River subpopulation goes back as far as 18884 with 

newspaper reports as far back as 18665, and the sport dip net fishery was first reported in 18656.

As there are no historical fishery-independent abundance estimates for eulachon, the historical 

landings data can be considered a minimum measure of fish abundance7. Based on the landings 

 

4 Ceremonial and subsistence fishery for Washington and Oregon Indian Tribes in the Columbia River Basin has taken 

place for thousands of years. However, there are no reliable records for landings. 

5 The Oregonian, 24 February, 1866. 

6 Huntington 1963.

7 There are no reliable landings data available for the sport dip net fishery other than an exploratory sampling program 

conducted by the Washington Department of Fish and Wildlife (WDFW) in 1978 on the Cowlitz River. Based on the 

information collected from this exploratory sampling program, WDFW estimated that the sport dip net fishery was 

comparable to the commercial harvest. WDFW memorandum—Cowlitz River smelt sport dip net fishery total catch 

estimate.
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data8, we estimated that in order to maintain harvest rates of 12,000,000 to 128,000,0009fish per 

year, the total run size would have to have been substantially higher than the estimated range of

adult eulachon harvested per year. 

The historical landings data for the Fraser River subpopulation goes back as far as 1881. As there 

are no historical fishery-independent abundance estimates for eulachon, the historical landings 

data can be considered a minimum measure of fish abundance. Based on the landings data10, we 

estimated that in order to maintain harvest rates of 90,000 to 8,000,00011 fish per year, the total 

run size would have to have had to have been substantially higher than the estimated range of

eulachon harvested per year. 

The historical landings data for the BC subpopulation goes back as far as 1877. As there are no 

historical fishery-independent abundance estimates for eulachon, the historical landings data can 

be considered a minimum measure of fish abundance. Based on the landings data12, we estimated

that in order to maintain harvest rates of 9,000 to 5,000,00013 fish per year, the total run size 

would have to have had to have been substantially higher than the estimated range eulachon 

harvested per year.

The historical landings data for the Klamath River subpopulation is extremely limited. The only 

reliable landings data is for 196314, when a total of 650,000 fish were reported to have been 

landed. Based on the limited nature of the data we cannot estimate the fraction of the harvest 

relative to the total run (escapement15). Nonetheless, what is known is that harvest of eulachon in 

the Klamath River has been documented for more than 100 years, albeit intermittently, as far 

back as 1879, and in the years 1919, 1963, 1968, 1969, 1976, 1978, 1979, and 198016.

 

8 Commercial harvest data is available from 1888 – 2017 for the whole Columbia River system (most years, a few 

missing) and broken down by state (early years) and/or tributaries (mostly after 1935). Harvest is reported as pounds 

landed (converted to numbers of fish). We restrict the data to the period 1936 – 1992 so that we have a consistent set 

of tributary data, and because earlier data may be more unreliable. The geometric mean of the commercial landings 

data for the years 1936 through 1992 (range) was 6,000,000 to 64,000,000 fish. All landings estimates were rounded.

9 Combined estimate – commercial and sport dip net fishery.

10 Commercial harvest data is available from 1881 – 2004 for the Fraser River. Harvest is reported as metric tons 

landed (converted to numbers of fish). We restrict the data to the period 1936 – 1992 so that we have a consistent set 

of data with the Columbia River, and because earlier data may be more unreliable.

11 The geometric mean of the commercial landings data for the years 1936 through 1992 (range) was 90,000 to 

8,000,000 fish. 

12 Harvest data is available from 1887 – 2009 for the BC subpopulation (multiple rivers). Harvest is reported as metric 

tons landed (converted to numbers of fish). We restrict the data to the period 1936 – 1992 so that we have a consistent 

set of data with the Columbia and Fraser River, and because earlier data may be more unreliable.

13 The geometric mean of the commercial landings data for the years 1936 through 1992 (range) was 9,000 to 

5,000,000 fish. In 2001 DFO conducted a spawning stock biomass estimation for the Skeena River with a median 

estimate of 10,733,968 fish, Lewis et al. 2009. 

14 Gustafson et al. 2010.

15 The amount of fish in a given population that does not get caught by commercial or recreational fisheries and return 

to their freshwater spawning habitat.

16 Gustafson et al. 2010.
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Therefore, one way to answer “what does recovery look like, and how will we know when we are 

there?” is to have sustained eulachon runs that provide harvest opportunities in-line with the 

historical landings data described herein for each subpopulation—plus an escapement multiplier

to sustain each of the four subpopulations across multiple generations.

Recovery Strategy

There is much uncertainty in our knowledge regarding how threats (Table ES-1) influence 

eulachon. Nonetheless, we propose to work on what we can to advance the conservation of 

eulachon by working with our stakeholders to continue to implement actions that further reduce 

the severity of threats to eulachon, as well as develop a comprehensive research program to 

collect the data to enable a greater understanding of eulachon population abundance and 

demographics, and improve our understanding of the impact that large-scale threats like climate 

change impacts on ocean conditions have on eulachon productivity, recruitment, and persistence.

Therefore, we have developed an approach that includes a set of priority actions and near-term 

research priorities to be implemented in years 1 through 5 to expedite funding and 

implementation of recovery actions that will reduce the severity of threats, and to kick-start the

research necessary to answer some of the questions needed to improve our understanding of the 

species and the linkages between threats, marine and freshwater environments, and the species.

Although we have identified a set of priority recovery actions and near-term research priorities, 

this in no way implies that all recovery actions identified in this Recovery Plan should wait to be 

implemented. Based on these initial results, we will then make adjustments, via adaptive 

management, to this Recovery Plan to implement recovery action in years 5 through 25.

Priority Actions 

 Establish a eulachon technical recovery and implementation team to develop an overall 

framework for funding, prioritization, implementation, and reporting of recovery actions. 

 Develop outreach and education strategies regarding the ecological, economic, and 

cultural values of eulachon; foster stewardship of the marine ecosystem; expand funding 

and research partnerships; and increase involvement of existing regional and international 

organizations.

 Continue to work with the ocean shrimp trawl fisheries and the states of California, 

Oregon, and Washington to implement actions, e.g., fleet-wide implementation of light 

emitting diode lights, rigid grate bycatch reduction devices, and additional gear-type or 

operational modifications, to further reduce bycatch of eulachon in the ocean shrimp 

trawl fisheries.

 Continue to work with the states to implement a limited-opportunity eulachon fishery to:

(1) provide essential context for interpreting historical harvest data to better understand 

trends and variability in eulachon abundance; (2) filling critical information gaps such as 
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the length and age structure of spawning eulachon, as well as the temporal and spatial 

distribution of the run; (3) supporting the cultural traditions of Northwest tribes who rely

on eulachon as a seasonally important food source; and (4) providing a limited public and 

commercial opportunity for eulachon harvest to maintain a connection between people 

and the eulachon resource. This connection is important to sustaining public engagement 

in eulachon conservation and recovery.

 Continue to work with Federal and non-Federal entities that maintain and operate dams 

and channel-spanning water control structures to develop and implement actions to 

reduce the ecological effects caused by water management operations on riverine and 

estuarine habitats to support the full-range of biological requirements for eulachon.

 Continue to work with the U.S. Army Corps of Engineers to develop and implement 

actions to reduce impacts from dredging, e.g., entrainment, on eulachon.

 Continue to work with the states of California, Oregon, and Washington to implement 

programs that improve water quality for temperature.

 Continue to work with Federal agencies and the states of California, Oregon, and 

Washington to implement programs, e.g., revetment breaching and removal, to reduce the 

impacts of shoreline construction on eulachon and their habitats.

Near-Term Research Priorities

Abundance and Productivity

 Conduct annual in-river spawning stock biomass surveys in spawning areas with a 

high-to-moderate spawning frequency to develop long-term, high resolution 

abundance estimations for each subpopulation of eulachon.

 Conduct a gap analysis to identify the data needs to develop an at-sea survey method 

to create a reliable index of eulachon abundance in the marine environment.

o Develop and implement an at-sea survey method to create a reliable index of 

eulachon abundance in the marine environment.

Spawning Habitat

 Conduct a gap analysis to identify the data needs to develop a survey method to map 

eulachon spawning areas, with an emphasis on identifying high density spawning 

areas, for each subpopulation.

o Implement a high resolution mapping survey to identify high density eulachon 

spawning areas for each subpopulation. 

Subpopulation Structure

 Conduct a gap analysis to identify the data needs to develop a genetic mixed stock 

baseline analysis of eulachon spawning subpopulations.

o Conduct a genetic baseline analysis of eulachon spawning subpopulations to 

determine subpopulation-population structure of eulachon throughout the 

range of the DPS.
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 Conduct a gap analysis to identify the data needs to develop a genetic mixed stock 

baseline analysis of eulachon in the marine environment.

o Conduct a genetic mixed stock baseline analysis of eulachon in the marine 

environment.

 Conduct a gap analysis to identify the data needs to develop a method to correlate inriver and marine abundance estimations of eulachon. 

o Conduct an analysis that correlates in-river and marine abundance estimations 

of eulachon. 

Species-Ecosystem Interactions

 Conduct a gap analysis to identify the data needs to develop an ocean ecosystem 

indicators model of eulachon marine survival in the California Current Ecosystem.

o Develop an ocean ecosystem indicators model of eulachon marine survival in 

the California Current Ecosystem to determine how short-term and long-term 

variability in ocean conditions affect eulachon abundance and productivity for 

each subpopulation.

Subpopulation Viability Criteria

 Conduct a gap analysis to identify the data needs, e.g., age composition, lengthweight relationship, intrinsic mortality rates, sex ratios, fecundity; necessary to 

parameterize a population viability analysis and develop abundance and productivity 

criteria for each subpopulation of eulachon.

o Develop abundance and productivity criteria for each subpopulation of 

eulachon.

In addition to the actions directed at eulachon and their habitats, there are hundreds of habitat 

restoration projects each year that are implemented in California, Oregon, and Washington aimed 

at improving riverine and estuarine habitats. Some of these habitat restoration actions, e.g., 

actions that improve water quality, are likely to improve riverine and estuarine habitats for 

eulachon as well, resulting in direct and indirect benefits to eulachon.

Recovery Goal, Objectives, and Delisting Criteria

Recovery Goal

The goal of this Recovery Plan is to:

1. Increase the abundance and productivity of eulachon.

2. Protect and enhance the genetic, life history, and spatial diversity of eulachon 

throughout its geographical range; and

3. Reduce existing threats to warrant delisting of the species. 
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Figure ES-1 is a conceptual model that illustrates the linkages of the recovery strategy with the 

goal, objectives, delisting criteria, and actions.

Figure ES-1. Recovery strategy conceptual model.

Recovery Objectives

The recovery goal can be subdivided into discrete component objectives that, collectively, 

describe the conditions necessary for achieving the recovery goal. The Eulachon Recovery Team 

identified four recovery objectives:

1. Ensure subpopulation viability. 

2. Conserve spatial structure and temporal distribution patterns.

3. Conserve existing genetic and life history diversity and provide opportunities for 

interchange of genetic material between and within subpopulations.
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4. Eliminate or sufficiently reduce the severity of threats.

Delisting Criteria 

The Eulachon Recovery Team determined that meeting the following measurable criteria will 

indicate when the recovery objectives have been sufficiently achieved to propose removal of 

eulachon from the Federal list of threatened and endangered species.

1. Abundance: Each of the four subpopulations is self-sustaining, i.e., each subpopulation 

has less than 5% probability of extinction in 100 years.

2. Productivity: Each subpopulation has a stable or increasing growth rate greater than 1 

across multiple generations.

3. Spatial Structure and Temporal Distribution: Eulachon subpopulations are distributed in a 

manner that insulates against loss from local catastrophic events and provides for recolonization of a subpopulation that is affected by such an event.

4. Genetic and Life History Diversity: Eulachon subpopulations exhibit high certainty that 

genetic and life history diversity is sufficient to sustain natural production across a range 

of conditions, and eulachon subpopulations exhibit high certainty that changes in 

phenotypical traits represent positive natural adaptations to prevailing environmental 

conditions.

5. Threats: For each subpopulation, the threats listed in Table ES-1 have been diminished 

such that they do not limit attainment of the desired biological status of the DPS, and all 

the factors in section 4(a)(l) of the ESA have been addressed.

This Recovery Plan covers the status, threats, recovery goals, objectives, and delisting criteria for 

eulachon at the species’ scale. However, for the most part17, the recovery actions in this 

document are specific to eulachon subpopulations within the jurisdiction of the U.S. For the 

Fraser River and British Columbia Coast subpopulations, NMFS will, to the extent feasible, 

collaborate with the Department of Fisheries and Oceans Canada (DFO) and First Nations in 

Canada to develop recovery actions to address threats to eulachon for the Fraser River and BC 

subpopulations.

 

17 Due to the nature of the threats eulachon face, e.g., climate impacts on ocean conditions, as well as the distribution 

of eulachon in the marine environment, actions to address the species’ and the threats it faces will cross political 

jurisdictions. 
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Adaptive Management

In conjunction with a research, monitoring, and evaluation plan, adaptive management plays a 

critical role in recovery planning. The long-term success of recovery efforts will depend on the 

effectiveness of incremental steps taken to move eulachon from its current status to a viable 

level, and to restore self-sustaining eulachon subpopulations in the U.S. and Canada. 

Adjustments will be needed if actions do not achieve desired goals, and to take advantage of new 

information and changing opportunities. Adaptive management provides the mechanism to 

facilitate these adjustments. 

Adaptive management works by binding decision making with data collection and evaluation. 

Most importantly, it offers an explicit process through which alternative approaches and actions 

can be proposed, prioritized, implemented, and evaluated. Successful adaptive management 

requires that monitoring and evaluation plans be incorporated into overall implementation plans 

for recovery actions. These plans should link monitoring and evaluation results explicitly to 

feedback on the design and implementation of actions. 

Figure ES-2. The adaptive management process. 
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Time and Cost Estimates

It is important to consider the unique challenges of estimating time and cost for eulachon 

recovery given the complex relationship of these fish to the environment and to human activities 

on land and water. NMFS estimates that it will take approximately 25 to 100 years for the 

southern DPS of eulachon to achieve recovery. The recovery plan contains an extensive list of 

actions to recover the subpopulations; however, it recognizes that there are many uncertainties 

involved in predicting the course of recovery and in estimating total costs over such a long 

recovery period. Such uncertainties include biological and ecosystem responses to recovery 

actions.

NMFS has developed a set of recovery actions and cost estimates based on the best information 

currently available. With the many uncertainties involved in predicting the course of recovery 

and in estimating total costs, we focused on the first five years of implementation and in fiveyear intervals thereafter to coincide with our 5-year status reviews, with the understanding that 

before the end of each five-year implementation period, specific actions and costs will be 

estimated for subsequent years. Based on recovery actions for which we have cost estimates, the 

cost of implementation in the U.S. jurisdiction over the first 5 fiscal years is $12,205,000. A

gross estimate for the total cost of recovery actions to be implemented in the U.S jurisdiction is 

between $21,358,750 (25 years) to $32,038,125 (100 years). After the first 5 years, we will 

reevaluate the status of eulachon based on the information gathered over this period. It should be 

possible to make better informed projections about the time for and expense of recovery as more 

information is obtained.
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Chapter 1. Introduction: Biology and Life History of Eulachon

Overview: The southern DPS of eulachon is comprised of fish that spawn in rivers south of the 

Nass River in British Columbia to, and including, the Mad River in California (Figure 1-1), and 

were listed as a threatened species18 under the ESA on March 18, 2012 (52 FR 13012). NMFS’ 

2016 ESA five-year review concluded that the DPS’s threatened designation remained 

appropriate.

The Biological Review Team (BRT) concluded that, starting in 1994, the southern DPS of 

eulachon experienced an abrupt decline in abundance throughout its range (Gustafson et al.

2010). Although eulachon abundance in monitored rivers improved in the 2013–2015 return 

years, recent conditions in the North East Pacific Ocean are likely linked to the sharp declines in 

eulachon abundance in monitored rivers in 2016 and 2017. The likelihood that these poor ocean

conditions will persist into the near future suggest that subpopulation declines may again be 

widespread in the upcoming return years. 

There are many “populations” of eulachon within the range of the species. For their threats 

analysis, the BRT did not include all known or possible eulachon spawning areas (Table A-1, 

Gustafson et al. 2010). As such, the BRT partitioned the southern DPS of eulachon into 

geographic areas, i.e., subareas/subpopulations, for their threats assessment. As such, the 

subpopulation structure used by the BRT leaves out some “populations” within the DPS, e.g., 

Elwha River, Naselle River, Umpqua River, Smith River, that we now know may have (or had) 

some important contribution to the overall productivity, spatial distribution, and genetic and life 

history diversity of the species. As such, it is impossible to know, whether or not, the DPS is one 

large metapopulation, where local spawning populations come and go and some areas are sinks 

and some are sources, or whether the DPS is comprised of multiple demographically independent 

populations. Therefore, until we have the data necessary to determine whether eulachon are one 

large metapopulation or comprised of multiple demographically independent populations, we 

will consider the four subpopulations identified by the BRT—the Klamath River, the Columbia 

River, the Fraser River, and the British Columbia coastal rivers—as the minimum set of 

“populations” that need to meet biologically-based (abundance, productivity, spatial distribution, 

and genetic and life history diversity) and threats-based delisting criteria in this Recovery Plan. 

A. Species Description

Eulachon are an anadromous smelt in the family Osmeridae. The genus Thaleichthys has only 

one species and valid subspecies have not been described (McAllister 1963). The binomial 

species name is derived from Greek roots; thaleia meaning rich, ichthys meaning fish, and 

pacificus meaning of the Pacific (Hart 1973). McAllister (1963) provides a taxonomic synonymy 

 

18 In this document, “the species” and “eulachon” refers to the Southern DPS of eulachon.
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for the species, which was originally described from the Columbia River as Salmo (Mallotus) 

pacificus by Richardson (1836). 

Eulachon have been classified previously in various other ways and placed in different genera 

(Scott and Crossman 1973), but the present systematic classification follows Mecklenburg et al. 

(2002): 

 Phylum: Chordata 

 Subphylum: Vertebrata 

 Superclass: Gnathostomata 

 Grade: Teleostomi 

 Class: Actinopterygii 

 Subclass: Neopterygii 

 Division: Teleostei 

 Subdivision: Euteleostei

 Superorder: Protacanthopterygii 

 Order: Osmeriformes 

 Suborder: Osmeroidei 

 Superfamily: Osmeroidea 

 Family: Osmeridae (smelts) 

 Genus and species: Thaleichthys pacificus (Richardson, 1836)

Common Names

English

Eulachon: derived from the Chinook jargon (Tsinuk Wawa), a synthetic trading language derived 

from French, English, and various First Nations languages (Hay and McCarter 2000); candlefish; 

less commonly salvation fish, saviour fish, fathom fish. 
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Native Languages 

Many variants of eulachon, including hoolakan, hooligan, hoolikan, olachan, ollachan, oolachan, 

oolichan, oulachan, oulachon, ulchen, ulichan, uthlecan; also yshuch, swavie, chucka, juk’wan or 

za’xwen meaning ‘jittery fish’ in Haisla language, saak in Tlingit. 

B. Distribution

Freshwater Distribution

Eulachon, an anadromous smelt in the northeast Pacific Ocean, is composed of numerous 

populations that spawn in rivers from northern California to southwestern Alaska (Figure 1-1). 

Figure 1-1. Distribution of eulachon spawning rivers (open circles) in the northeast Pacific 

Ocean (Gustafson et al. 2010).

In the portion of the species’ range that lies south of the U.S.–Canada border, most eulachon 

production originates in the Columbia River Basin, including the Columbia River, the Cowlitz 

River the Grays River, the Kalama River, the Lewis River, and the Sandy River (Gustafson et al. 

2010). 

Smith and Saalfeld (1955) stated that eulachon were occasionally reported to spawn up to the 

Hood River on the Oregon side of the Columbia River prior to the construction of Bonneville 
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Dam in the 1930s. In times of great abundance (e.g., 1945, 1953), eulachon have been known to 

migrate as far upstream as Bonneville Dam (Smith and Saalfeld 1955, WDFW and ODFW 2008;

as cited in Gustafson et al 2010) and may extend above Bonneville Dam by passing through the 

ship locks (Smith and Saalfeld 1955). Eulachon likely reached the Klickitat River on the 

Washington side of the Columbia River in 1945 via this route (Smith and Saalfeld 1955). 

Williams (2009, as cited in Gustafson et al. 2010) also reported on the onetime observation by an 

ODFW stream surveyor in February 1991 of eulachon in Conyers Creek, a tributary of the 

Clatskanie River, which is in turn a tributary of the lower Columbia River on the Oregon side of 

the river. The stream surveyor reported that eulachon were seen holding in pools within the 

lower 0.8 km (0.5 mile) of Conyers Creek during a daytime flood tide, but none were observed in 

the main stem of the Clatskanie River. 

Historically, the only other large river basins in the contiguous United States where large, 

consistent spawning runs of eulachon have been documented are the Klamath River in northern 

California and the Umpqua River in Oregon. However, eulachon have been found both 

frequently and infrequently in several, but not all, coastal rivers in northern California (including 

the Mad River, Redwood Creek, and Humboldt Bay in California (Monaco et al. 1990, Willson 

et al. 2006; as cited in Gustafson et al 2010); Oregon (including Tenmile Creek the Siuslaw 

River, the Winchuck River, the Chetco River, the Pistol River, the Rogue River, the Elk River,

the Sixes River, the Coquille River, the Coos River, the Yaquina River, Hunter Creek, and

Euchre Creek (Willison et al. 2006, as cited in Gustafson et al. 2010); Washington (including the 

Elochoman River, the Washougal River, Germany Creek, Mill Creek, Willapa Bay (North, 

Naselle, Nemah, Bear, and Willapa Rivers), Grays Harbor (Humptulips, Chehalis, and 

Wynoochee Rivers), the Copalis, Moclips, Quinault, Queets, and Bogachiel Rivers, the Elwha 

River, as well as Puget Sound (Monaco et al. 1990, Willson et al. 2006; as cited in Gustafson et 

al. 2010). 

Eulachon may have historically occurred in the Sacramento River system and even farther south 

along the California and Baja California coast, in areas where they may have been extirpated 

(Minckley et al. 1986, as cited in Willson et al 2006). Although Minckley et al. (1986, their 

Table 15.1, p. 541; as cited in Willson et al 2006) indicate that eulachon were native to the 

Sacramento River and drainages within the south California Coastal to Baja California region, no 

verifying references for these assertions were given. In 2007 Vincik and Titus (California 

Department of Fish and Game) reported on the capture of a single mature male eulachon in a 

screw trap at RKM 228 (RM 142) on the Sacramento River (Gustafson et al. 2010). 

In the portion of the species’ range that lies north of the U.S.–Canada border, a large portion of 

eulachon production originates in the Fraser River. Early reference to eulachon being caught by 

First Nations groups on the Fraser River in 1827–1830 appear in the journals of the Hudson’s 

Bay Company post Fort Langley, located on the south bank of the lower Fraser River near the 

Salmon River (MacLachlan 1998, as cited in Gustafson et al. 2010). 
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In British Columbia, north of the Fraser River, eulachon production originates in the Kingcome 

River (Berry and Jacob 1998, as cited in Gustafson et al. 2010), Wannock River (Berry and 

Jacob 1998, Moody 2008, as cited in Gustafson et al. 2010), Bella Coola River (Moody 2008), 

Kemano River (Lewis et al. 2002, Ecometrix 2006; as cited in Gustafson et al. 2010), Kitimat 

River (Pedersen et al. 1995, Kelson 1997, Ecometrix 2006; as cited in Gustafson et al. 2010 ), 

Skeena River (Lewis, 1997, Stoffels 2001; as cited in Gustafson et al. 2010), and the Nass River 

(Langer et al. 1977, as cited in Gustafson et al. 2010) 

In Alaska, Moffitt et al. (2002, as cited in Gustafson et al. 2010) indicated that at least 35 rivers 

have spawning runs of eulachon, including one in a glacial stream on Unimak Island, the first 

island in the Aleutian Island chain off the western end of the Alaska Peninsula. Aspects of the 

biology of eulachon have been studied in the Stikine River (Franzel and Nelson 1981, as cited in 

Gustafson et al. 2010), the Taku River (Flory 2008b, as cited in Gustafson et al. 2010), the 

Chilkoot River (Betts 1994, as cited in Gustafson et al. 2010), the Chilkat River (Mills 1982, 

Betts 1994; as cited in Gustafson et al. 2010), the Copper River (Moffitt et al. 2002, as cited in 

Gustafson et al. 2010), the Eyak River, the Alaganik River (Moffitt et al. 2002, Joyce et al. 2004; 

as cited in Gustafson et al. 2010), Twentymile River (Kubik and Wadman 1977, 1978, Spangler 

2002, Spangler et al. 2003; as cited in Gustafson et al. 2010 ), and the Susitna River (Barrett et 

al. 1984, Vincent-Lang and Queral 1984; as cited in Gustafson et al. 2010). 

Oceanic Distribution 

Although they spend 95–98% of their lives at sea (Hay and McCarter 2000), little is known 

concerning the saltwater existence of eulachon. They are reported to be present in the “food rich” 

and “echo scattering layer” of coastal waters (Barraclough 1964, p. 1,337; as cited in Gustafson 

et al, 2010), and “in near-benthic habitats in open marine waters” of the continental shelf 

between 20 and 150 m depth (Hay and McCarter 2000, p. 14). Hay and McCarter (2000, their 

Figure 5) illustrated the offshore distribution of eulachon in British Columbia as determined in 

research trawl surveys, which indicate that most eulachon were taken at around 100 m depth, 

although some were taken as deep as 500 m and some at less than 10 m. Schweigert et al. (2007, 

p. 11, as cited in Gustafson et al. 2010) stated that “the marine distribution of adults in British 

Columbia includes the deeper portions of the continental shelf around Dixon Entrance, Hecate 

Strait, Queen Charlotte Sound, and the west coast of Vancouver Island, generally at depths of 

80–200 m.” Mueter and Norcross (2002, as cited in Gustafson et al. 2010) reported eulachon 

were present in 32% of triennial bottom trawl surveys on the upper slope and continental slope in 

the Gulf of Alaska between 1984 and 1996 and were caught at depths down to 500 m in the 

Kodiak, Yakutat, and southeast areas of Alaska. Armstrong and Hermans (2007, as cited in 

Gustafson et al. 2010) indicated that eulachon are commonly caught in trawls in the coastal 

fjords of southeast Alaska. 

Smith and Saalfeld (1955, p. 12, as cited in Gustafson et al. 2010) reported the occasional 

capture of eulachon in the offshore “otter trawl fishery,” particularly in November to January 
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near the mouth of the Columbia River “as the mature smelt approach the Columbia River.” 

Emmett et al. (2001) reported the capture of small numbers of eulachon by nighttime surface 

trawls targeted on pelagic fishes off the Columbia River in April to July of 1998 and 1999. 

About 10% of hauls in 1999 contained from one to a maximum of eight eulachon (Emmett et al. 

2001). Eulachon also occur as bycatch in some U.S.-based groundfish fisheries (Bellman et al. 

2008) off the U.S. West Coast and more commonly in the California and Oregon ocean shrimp 

(Pandalus jordani) fisheries (NWFSC 2008, as cited in Gustafson et al. 2010). The Pacific 

Fishery Management Council has prohibited at-sea directed harvest of eulachon in U.S. West 

Coast waters and eulachon are not an actively managed or monitored species (PFMC 2008, as 

cited in Gustafson et al. 2010); therefore there is a paucity of data on at-sea distribution of 

eulachon off the U.S. West Coast.

C. Morphology

Eulachon are a slender-bodied fish with an average weight of 40 grams (g) and typically reach 

150 to 200 millimeters (mm) standard length, although a few may reach 250 mm standard length. 

Eulachon have compressed, elongated bodies and large mouths, the maxilla usually extending 

just past the middle of the eye (Moyle 1976). The operculum possess strong concentric striations 

and the pectoral fins, when pressed against the body, reach about two-thirds of the way to the 

bases of the pelvic fins. The lateral line is complete, with 7 to 78 scales. There are 8 to 11 pyloric 

ceca, 18 to 23 dorsal rays, 8 pelvic rays, 10 to 12 pectoral rays, 18 to 23 anal rays, 17 to 23 

slender gill rakers on the first arch, and 7 to 8 branchiostegal rays (Moyle 1976). The jaws have 

small, pointed teeth which may be missing from spawning fish, especially males. The lining of 

the gut cavity is pale with dark speckles. Live fish are dark brown to dark blue on the back and 

head with a silvery white belly and unmarked fins. Spawning males develop a distinct midlateral 

ridge and numerous distinct tubercles on the head, body, and fins. Females may also have 

tubercles but they are poorly developed (Moyle 1976). 

Sexual Dimorphism 

Spawning male eulachon can be told readily from females by the rougher skin produced by 

tubercles on the scales, especially near the lateral line and on the head, by a more rigid body and 

less cylindrical cross section caused by a raised lateral ridge, and by slightly larger paired fins 

(Hart and McHugh 1944, Hay and McCarter 2000, as cited in Willson et al 2006). Lewis et al. 

(2002, as cited in Willson et al. 2006) note that in another species of smelt, the lateral ridges of 

the males are used to press females down to the substrate, perhaps encouraging extrusion of 

eggs. Females also have more abdominal vertebrae (Hart and McHugh 1944, as cited in Willson

et al. 2006). Males often tend to be slightly larger than females, even when controlling for age 

(Willson et al. 2006), but are not always larger (Warner and Shafford 1979, Langer et al 1977; as 

cited in Willson et al. 2006). Morphological hermaphrodites are sometimes reported (Lewis et al 

2002, as cited in Willson et al. 2006). 
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D. Genetic Differentiation

The BRT reviewed four published genetic studies of genetic population structure in eulachon. 

One of these studies (McLean et al. 1999) used RFLP analysis to examine variation in 

mitochondrial deoxyribonucleic acid (mtDNA). The other studies (McLean and Taylor 2001, 

Kaukinen et al. 2004, Beacham et al. 2005) analyzed microsatellite loci. 

McLean et al. (1999) examined mtDNA variation in two fragments (each containing two genes 

NADH-5/NADH-6 and 12S/16S rRNA) in 285 eulachon samples collected at 11 freshwater sites 

ranging from the Columbia River to Cook Inlet, Alaska, and also in 29 ocean-caught fish 

captured in the Bering Sea. Samples were taken at two sites (Columbia and Cowlitz Rivers) in 

two years and all other locations were sampled in single years. Overall, 37 mtDNA composite 

haplotypes were observed in the study. Two haplotypes were found in all sampling locations and 

together accounted for approximately 67% of the samples in the study. Eight additional 

haplotypes were present at multiple sites and the remaining 27 haplotypes were “private” (found 

only in one location). 

An analysis of the nucleotide substitutions separating the 37 haplotypes revealed that the 

haplotypes were all closely related, with the number of substitutions ranging between 1 and 13. 

The mtDNA haplotypes clustered into two major groups and the frequencies of the two 

haplotype groups differed among sampling sites, particularly in the Alaska and Bering Sea 

collections compared to samples from further south, although these differences were not 

statistically significant. Approximately 97% of mtDNA variation occurs within populations and 

about 2% is found among regions (FST = 0.023). McLean et al. (1999) also found that genetic 

distance among sampling locations was correlated with geographic distance (r2 = 0.22, P = 

0.0001). Based on these results, McLean et al. (1999) concluded that there was little genetic 

differentiation among distinct freshwater locations throughout the eulachon range. However, 

McLean et al. (1999) noted that association of geographic distance and genetic differentiation 

among eulachon populations suggested an emerging population subdivision throughout the range 

of the species. 

In a later study, McLean and Taylor (2001) used five microsatellite loci to examine variation in 

the same set of populations as McLean et al. (1999). The populations in the Columbia and 

Cowlitz rivers were represented by 2 years of samples with a total sample size of 60 fish from 

each river. However, several populations were represented by very few samples including just 5 

fish from the 3 rivers in Gardner Canal and just 10 fish from the Fraser River. Results from a 

hierarchical analysis of molecular variance test were similar to that of the McLean et al. (1999) 

mtDNA study, with 0.85% of variation occurring among large regions and 3.75% among 

populations within regions. 

Tests of differentiation were significant among several pairs of populations in the microsatellite 

study (27% of tests after correction for multiple comparisons), particularly comparisons that 
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included populations in the Columbia and Cowlitz rivers and those with the Nass River sample 

and samples taken further south. FST (a commonly used metric to evaluate population 

subdivision) was estimated as 0.047 when sample sites were considered separately, and was 

significantly different from zero. In contrast to the mtDNA analysis, genetic distances among 

populations using these five microsatellite loci were not correlated with geographic distances. 

Overall, however, McLean and Taylor (2001) concluded that their microsatellite results were 

mostly consistent with the mtDNA findings of McLean et al. (1999) and that both studies 

indicated that eulachon have some degree of population structure. 

The most extensive study of eulachon, in terms of sample size and number of loci examined, is 

that of Beacham et al. (2005). Beacham et al. (2005) examined microsatellite DNA variation in 

eulachon collected at 9 sites ranging from the Columbia River to Cook Inlet, Alaska, using the 

14 loci developed by Kaukinen et al. (2004). Sample sizes per site ranged from 74 fish in the 

Columbia River to 421 from the Fraser River. Samples collected in multiple years were analyzed 

from populations in the Bella Coola and Kemano rivers (2 years of sampling) and also in the 

Nass River (3 years of sampling). 

Beacham et al. (2005) observed much greater microsatellite diversity within populations than 

that reported by McLean and Taylor (2001) and all loci were highly polymorphic in all of the 

sampled populations. Significant genetic differentiation was observed among all comparisons of 

the nine populations in the study and FST values for pairs of populations ranged from 0.0014 to 

0.0130. A cluster analysis of genetic distances showed genetic affinities among the populations 

in the Fraser, Columbia, and Cowlitz rivers and also among the Kemano, Klinaklini, and Bella 

Coola rivers along the central British Columbia coast. In particular, there was evidence of a 

genetic discontinuity north of the Fraser River, with Fraser and Columbia/Cowlitz samples being 

approximately 3–6 times more divergent from samples further to the north than they were to 

each other. Similar to the mtDNA study of McLean et al. (1999), Beacham et al. (2005) also 

found that genetic differentiation among populations (FST) was correlated with geographic 

distances (r = 0.34, P < 0.05). 

Beacham et al. (2005) found stronger evidence of population structure than the earlier genetic 

studies, and concluded that their results indicated that management of eulachon would be 

appropriately based at the level of the river drainage. In particular, the microsatellite analysis 

showed that populations of eulachon in different rivers are genetically differentiated from each 

other at statistically significant levels. The authors suggested that the pattern of eulachon 

differentiation was similar to that typically found in studies of marine fish, but less than that 

observed in most salmon species. 

Although Beacham et al. (2005) found clear evidence of genetic structure among eulachon 

populations; the authors also noted that important questions remained unresolved. The most 

important one in terms of identifying a DPS or DPSs for eulachon is the relationship between 

temporal and geographic patterns of genetic variation. In particular, Beacham et al. (2005) found 
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that year-to-year genetic variation within three British Columbia coastal river systems was 

similar to the level of variation among the rivers, which suggests that patterns among rivers may 

not be temporally stable. However, in the comparisons involving the Columbia River samples, 

the variation between the Columbia samples and one north-of-Fraser sample from the same year 

was approximately five times greater than a comparison within the Columbia from two different 

years. Taken together, there appears to be little doubt that there is some genetic structure within 

eulachon and that the most obvious genetic break appears to occur in southern British Columbia 

north of the Fraser River. 

Two genetic studies have been published since the 2010 status review (Gustafson et al. 2010) 

was released, one utilizing microsatellite DNA differentiation to study population structure 

among samples of eulachon in Alaska (Flannery et al. 2009, 2013; as cited in Gustafson 2016) 

and another utilizing newly developed putatively neutral and adaptive single nucleotidepolymorphisms (SNPs) (Candy et al. 2015; as cited in Gustafson 2016). 

Flannery et al. (2009, 2013; as cited in Gustafson 2016) examined eulachon population structure 

among 26 rivers in Alaska by analyzing variation at the same 14 microsatellite DNA loci used by 

Beacham et al. (2005) to analyze population structure in British Columbia and the Columbia 

River. All collections occurred in either 2003 or 2004, and there was no temporal sampling at 

any of the 26 locations (Flannery et al. 2013; as cited in Gustafson 2016). Eulachon in Alaska 

exhibited a low degree of genetic divergence, with a broad scale regional level of population 

structure. Samples from the northern region (Yakutat Forelands, Cook Inlet, and Prince William 

Sound) were significantly different from samples obtained from the southern region (Behm and 

Lynn canals, Stikine Strait, and Berners Bay) (Flannery et al. 2013; as cited in Gustafson 2016); 

however, there was little inter-regional differentiation. According to Flannery et al. (2013, p. 

1040; as cited in Gustafson 2016), “The level of genetic divergence between regions was four 

times as great as that within regions.” The fine scale genetic population structure that Beacham 

et al. (2005) described, based on samples of eulachon from British Columbia and the Columbia 

River, was absent in Alaskan eulachon (Flannery et al. 2013; as cited in Gustafson 2016. 

Candy et al. (2015; as cited in Gustafson 2016) examined eulachon population structure among 

12 sampling locations ranging from Washington (Columbia and Cowlitz rivers) to south-central 

Alaska (Twenty-mile and Kenai rivers in Cook Inlet) by analyzing genetic variation among a 

panel of 3,911 putatively neutral SNPs and a panel of 193 putatively adaptive SNPs. There was 

no temporal sampling at any of the 12 locations included in the study by Candy et al. (2015; as 

cited in Gustafson 2016). 

According to Candy et al. (2015), the neutral and adaptive eulachon SNP panels showed a 

regional population structure that was similar to that observed by Beacham et al. (2005) using 

microsatellite DNA markers. Candy et al. (2015; as cited in Gustafson 2016) interpreted their 

results as indicating that: 
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... there is a three-population southern Columbia-Fraser group (Cowlitz, Columbia, and 

Fraser rivers), a seven-population British Columbia (BC) – SE Alaska group (Stikine, 

Nass, Skeena, Klinaklini, Kingcome, Kemano and Bella Coola rivers) and a twopopulation northern Gulf of Alaska (GOA) group (Twenty Mile and Kenai rivers)

Surprisingly, pairwise FST comparisons for the neutral SNPs showed that Columbia River 

eulachon were not significantly differentiated from any other population (all pairwise FST ≤ 

0.0000) (Candy et al. 2015, their table 2; as cited in Gustafson 2016). However, the adaptive 

SNPs displayed statistically significant pairwise FST values for the Columbia River sample 

compared to all other rivers, with the exception of the Cowlitz River. The Columbia River 

sample consisted of larval eulachon collected downstream of the Cowlitz River, so these larvae 

may have originated from the Cowlitz River (Candy et al. 2015; as cited in Gustafson 2016). 

Small et al. (2015; as cited in Gustafson 2016) described preliminary results of a study using 

microsatellite DNA variation to examine potential temporal differences in genetic population 

structure of eulachon in the Columbia River Basin. Samples examined included: 1) 95 larval 

samples from the putative “pilot run” in the Cowlitz River; 2) a mainstem Columbia River 

collection of 95 larval eulachon near the end of the larval outmigration period; and 3) 95 tissue 

samples from Sandy River eulachon. Additional eulachon samples were also analyzed from 

samples collected near Ucluelet and Pachena Bay, offshore of the west coast of Vancouver 

Island (WCVI) (Small et al. 2015; as cited in Gustafson 2016). The pilot run samples proved not 

to be eulachon, and the mainstem larval Columbia River samples and Sandy River sample were 

genetically indistinguishable. The pilot run samples were most likely longfin smelt (Spirinchus 

thaleichthys), another closely related anadromous osmerid, and not eulachon. Considering that 

Sandy River eulachon are the latest spawning population in the Columbia River Basin it is not 

surprising that they would be genetically similar to larvae collected downstream of the Sandy 

River at the end of the larval outmigration period in the Columbia River mainstem. Small et al. 

(2015; as cited in Gustafson 2016) also stated that samples collected off of WCVI showed no 

detectable genetic differences with Columbia River eulachon. Earlier studies (Schweigert et al. 

2012; as cited in Gustafson 2016) had determined that about 56% of eulachon collected off of 

WCVI could be genetically assigned as originating in the Columbia River. More recent 

estimates indicate that about two-thirds of the eulachon collected off WCVI could be genetically 

assigned back to the Columbia River19.

E. Body Composition 

Eulachon have a high energy density, averaging 7.7 kcal/g ash-free dry mass, markedly higher 

than herring (Clupea pallasi) and capelin (Mallotus villosus) (6.8 and 6.6 kcal/g, respectively) or 

 

19 Sean MacConnachie, Fisheries and Oceans Canada, Nanaimo, BC, Canada. Powerpoint presentation at Eulachon 

State of the Science and Science to Policy Forum, Portland, OR., August 21, 2015.
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cod, pollock, and arrowtooth flounder (5.5-5.8 kcal/g) (Perez 1994, as cited in Willson et al. 

2006). Specimens from the Gulf of Alaska had significantly higher caloric content in March (7.8 

kcal/g; before spawning, for most populations) than in August (7.5 kcal/g) (Willson et al. 2006). 

Eulachon are notable for the high concentration of oils (mostly mono-unsaturated fatty acids, 

particularly oleic acid (Kuhnlein et al. 1982, as cited in Willson et al. 2006) in the body. Among 

the lipids occurring in eulachon is squalene, which is typical of elasmobranchs rather than 

teleosts (Ackman et al. 1968, as cited in Willson et al. 2006). The fatty-acid ‘signature’ of 

eulachon is quite distinct from that of other species of forage fishes (Iverson et al. 2002, as cited 

in Willson et al. 2006). Samples collected in March and April contained 18% lipids (wet mass; 

Willson et al. 2006). There was a slight but significant increase in body lipids of Gulf of Alaska 

eulachon from February-March to June-September (Payne et al. 1999, as cited in Willson et al. 

2006). 

Samples obtained from February to June in the Gulf of Alaska contained 18-20% oil (wet mass), 

a value higher than that for other common forage fishes, such as sand lance (Ammodytes 

hexapterus; 3-6%) or capelin (2-10%) during the same time frame (Payne et al. 1999, Ref. 35

Willson et al. 20060). Iverson et al. 2002, as cited in Willson et al. 2006 reported similar average 

values for spring samples from Prince William Sound (eulachon 19% lipid [wet mass], capelin 

3%, but sand lance 1.5%). “Large” (>100 mm standard length) eulachon from the northern Gulf 

of Alaska, collected from May to September, contained 50% lipid (by dry mass; (approximately 

equivalent to 14.5% lipid by wet mass), similar to the lipid content of northern lampfish 

(Stenobrachius leucopsarus) but higher than lipid content from capelin, sand lance, or herring 

(Anthony et al. 2000, as cited in Willson et al. 2006). 

Protein content was slightly lower for eulachon (12-13%) than for the other species (13-15% for 

capelin, 16-18% for sand lance) (Payne et al. 1999, as cited in Willson et al. 2006). When 

samples from the Gulf of Alaska and the eastern Bering Sea were matched for body size and 

month, there were no differences in protein and lipid content (Payne et al. 1999, as cited in 

Willson et al. 2006). Eulachon from the Columbia River were reported to have about 13-15% 

protein and 5-9% oil in muscle tissue (Stansby 1976, as cited in Willson et al. 2006). Eulachon 

also contain high levels of vitamins A and E (Kuhnlein et al. 1996, as cited in Willson et al. 

2006) and are good sources of calcium, iron, and zinc (Kuhnlein et al. 1996, as cited in Willson

et al. 2006). 

Eulachon can take up and store pollutants from their spawning rivers, despite the fact that they 

do not feed in fresh water and remain there only a few weeks (Rodgers et al. 1990, 

WDFW/ODFW 2001; as cited in Willson et al. 2006); eulachon avoid polluted waters when 

possible (Smith and Saalfeld 1955). Specimens from the Cowlitz River in Washington contained 

phenolics derived from the eruption of Mount St. Helens (Campbell et al. 1982, as cited in 

Willson et al. 2006). Eulachon returning to the lower Fraser River contained contaminants from 

wood-treatment processes (Rodgers et al. 1990, as cited in Willson et al. 2006), apparently 
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acquired after river entry (Birtwell et al. 1988, Rodgers et al. 1990; as cited in Willson et al. 

2006). Concentrations of some contaminants differed between males and females and increased 

with increasing distance upstream (Rodgers et al. 1990, as cited in Willson et al. 2006). 

Industrial effluent into the Kitimat River after 1972 has tainted eulachon flesh and made it 

unpalatable (Mikkelson et al. 1996, as cited in Willson et al. 2006). Nass River eulachon 

acquired detectable levels of metals derived from mine tailings (Futer and Nassichuk 1983, as 

cited in Willson et al. 2006). However, contaminant levels in eulachon (the edible portion only) 

from the Nass, Kitimat, Bella Coola, Kingcome, and Knights Inlet rivers were judged to be 

below the limits set by health regulations, although they increased from north to south (Futer and 

Nassichuk 1983, Chan et al. 1996, Kuhnlein et al. 1996; as cited in Willson et al. 2006).

F. Age, Growth, and Maturation 

Age determination of eulachon is reported to be difficult, because both otoliths and scales may 

yield inaccurate assessments, and age estimates from otoliths are commonly 1-3 years higher 

than estimates from scales (Ricker et al. 1954, as cited in Willson et al. 2006). This discrepancy 

occurred for Fraser River fish, but there was much better correspondence of age estimates from 

the two methods in eulachon from the Nass River (Langer et al. 1977, as cited in Willson et al. 

2006). Methodological differences may account for some of the differences among reports in the 

age of eulachon at spawning. 

Age at Spawning 

Most studies conclude that eulachon commonly spawn at age 3 or 4, but some fish spawn at age 

2 or age 5 (Barrett et al. 1984, as cited in Willson et al. 2006); some 9-year old adults are 

recorded from the Columbia River system (Washington Department of Fish and Wildlife and 

Oregon Department of Fish and Wildlife 2001). The mean age of fish in the Meshik River was 

3.1 years, with a few fish of ages 2, 4, and 5 years (based on otoliths, Warner and Shafford 1979, 

as cited in Willson et al. 2006), and the dominant age class on the Susitna River was 3 years 

(Willson et al. 2006). Biologists on the Kalsin River in Kodiak, Alaska reported, on the basis of 

otolith analysis, that most fish were 2 years old, some were 3 years old, and a few were 4 years 

old (Blackburn et al. 1981, as cited in Willson et al. 2006). On the Twentymile River, spawners 

ranged from age 2 to age 5 (and a few age-1 females in one year), but most spawners were age 3, 

with a broader distribution of ages in 2000 than in 2001 (Spangler 2002, as cited in Willson et al. 

2006). In the Copper River, spawning eulachon ranged from 2 to 6 years old, with age-4 fish 

predominant in one year and age-5 fish in another (Moffitt et al. 2002, as cited in Willson et al. 

2006). On the Stikine River, incoming fish were 2-4 years old; 3-year-olds were most common, 

and the frequency of 2- and 4-year-olds differed between sample years (based on otolith analysis; 

Franzel and Nelson 1981, as cited in Willson et al. 2006). 

There was annual variation in the dominant year class of spawners in the Nass River also, with 3-

year-olds dominant in one year and 4-year-olds in another Willson et al. 2006). Kitimat River 
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female eulachon, aged by otoliths, were mostly age 3, with some age 4, 5, and 6 years (Willson

et al. 2006), but the dominant age class in the Kemano River was 4 years (range 2-7 years, Lewis 

et al. 2002; Triton 1990 (in Pedersen et al. 1995); as cited in Willson et al. 2006). By scale and 

otolith analysis, most Fraser River fish spawned at age 2 and a few at age 3 according to Hart 

and McHugh (1944, as cited in Willson et al. 2006), but most spawned at age 4-5 (and a few up 

to age 7) according to other researchers (otolith analysis; Higgins et al. 1987, Ref. 215; Rogers et 

al. 1990, Ref. 375). Most fish in the Columbia River were age 3-4, with some fish age 5 (based

on otoliths: Smith and Saalfeld 1955; WDFW/ODFW 2001). Judging from research to date, the 

age distribution of eulachon in a spawning run probably varies among rivers. It also varies 

between sexes in some years and among years in the same river system (in the Kemano River, 

Lewis et al. 2002, as cited in Willson et al. 2006). 

Age and Length 

It is difficult to compare body lengths among reports because different length measures 

(standard, fork, total) have been used. We lack the data to convert one measurement to another, 

and reports sometimes may not state which measurements were used, so here we merely 

summarize the findings. As expected, both length and body mass increase with age (Willson et 

al. 2006). Eulachon on the Twentymile River averaged about 180-200 mm and 40-58 g at age 2, 

to 220-225 mm and 80-90 g at age 5; at age 3, the most common age of spawners, fork length 

averaged about 200-215 mm and body mass averaged about 60-65 g (estimated from graph, 

Spangler 2002, as cited in Willson et al. 2006). For the Fraser River population, fork-length 

distribution was as follows: age 0+ fish were about 20-50 mm, age 1+ about 50-80 mm, age 2+ 

about 75-105 mm, age 3+ about 105-135 mm, and age 4+ about 135-160 mm (estimated from 

graph; Barraclough 1964, as cited in Willson et al. 2006). Eulachon in the Kemano, Kitimat, 

Nass, Stikine, and Columbia rivers reportedly have similar distributions of size-at-age, but the 

increase of size-at-age is small for both sexes (10 mm and 7.2 g from age 3 to 4, 4 mm and 3.1 g 

from age 4 to 5; Lewis et al. 2002, as cited in Willson et al. 2006). 

Despite the assorted measurements reported regarding body size, it is clear that body size differs 

among river systems. Some reports indicate annual variation as well, so some of the apparent 

variation among river systems might also reflect differences among years. As noted by Spangler 

(2002, as cited in Willson et al. 2006), body size of eulachon at the northern and western end of 

their geographic range seems to be greater than in the south and east. Average body length in the 

Twentymile, Susitna, and Meshik rivers all exceed 200 m, whereas small samples from the 

Oregon coast indicate much smaller body lengths there. 

Fecundity 

Hart and McHugh (1944, as cited in Willson et al. 2006) noted that fecundity in the Fraser River 

ranged about 17,300–39,600 eggs in female eulachon measuring 145–188 mm SL. Average 

fecundity was about 25,000 eggs per female (Willson et al. 2006). Smith and Saalfeld (1955, p. 
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22) report a fecundity of 20,000–60,000 for female eulachon ranging 140–195 mm length from 

the Columbia River. Both Clemens and Wilby (1967) and McPhail and Lindsey (1970, as cited 

in Willson et al. 2006) report fecundity to be about 25,000 eggs in an average size female. Hay 

and McCarter (2000, as cited in Willson et al. 2006) reported total fecundity range of 20,000–

40,000 eggs, the number generally increasing with fish size. Depending on fish size, fecundity 

can range 7,000–31,000 eggs on the Columbia River (Willson et al. 2006). 

Cowlitz River—during the run year (2014-2015), the Cowlitz Tribe carried out systematic 

plankton tows in the Cowlitz River with the intent to develop an SSB estimate for that tributary 

of the Columbia River (Langness et al. 2015, as cited in Gustafson 2016). The Cowlitz River 

SSB estimation can be compared to the mainstem Columbia River eulachon SSB estimation 

(being done by WDFW), to see how much of the Columbia River eulachon production during 

2014-2015 is attributable to the Cowlitz River (Langness et al. 2015, as cited in Gustafson 2016). 

Preliminary estimates of the mean cumulative plankton flux of eulachon eggs and larvae in the 

Cowlitz River in 2015 was on the order of about 690 billion20, which is about 34% of the 

calculated total eulachon plankton flux for the Columbia River Basin, above the Grays River, of 

about 2 trillion, as calculated by Langness (2015, as cited in Gustafson 2016). Using a sex ratio 

of 4.33 males to females and an estimated fecundity of 35,155 eggs per female (derived from 

sampling in the Cowlitz River) an SSB of approximately 4,400 mt for the Cowlitz River in 2015 

was calculated.21 This equates to approximately 108 million spawning eulachon in the Cowlitz 

River in 201522.

Naselle River—in 2015, WDFW began plankton tows in the Naselle River, a tributary of 

Willapa Bay, in order to produce a eulachon SSB estimate (Langness 2015, as cited in Gustafson 

2016). Using the same methods described above for estimating the Columbia River SSB, 

WDFW estimated that mean eulachon egg and larval production was over 592 million in 2015. 

Mean egg and larval density was ~12 per cubic meter over the 17 days of sampling, and mean 

estimated SSB amounted to 1.5 mt for the period between 11 January and 23 May 2015 (Table 5, 

Langness 2015; as cited in Gustafson 2016). An estimated 36,400 eulachon spawned in the 

Naselle River in 2015 (Table 5, Langness 2015; as cited in Gustafson 2016). 

Chehalis River—the Quinault Indian Tribe (QIN 2014, as cited in Gustafson 2016) 

sampled for eulachon larvae during 2013 and 2014 in the Chehalis River, a tributary of Grays 

Harbor, Washington. In 2013 and 2014, 29 and 66 larval eulachon were captured, respectively. 

Putative eulachon larvae were captured in 5% of samples (19/360) in 2013 and in 9% of samples 

 

20 Nathan Reynolds, Cowlitz Indian Tribe. Powerpoint presentation at Eulachon State of the Science and Science to 

Policy Forum, Portland, OR., August 21, 2015.

21 Nathan Reynolds, Cowlitz Indian Tribe. Powerpoint presentation at Eulachon State of the Science and Science to 

Policy Forum, Portland, OR., August 21, 2015.

22 Nathan Reynolds, Cowlitz Indian Tribe. Powerpoint presentation at Eulachon State of the Science and Science to 

Policy Forum, Portland, OR., August 21, 2015.
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(34/377) in 2014 (QIN 2014, as cited in Gustafson 2016). After normalization of data, (QIN 

2014, p. 24, as cited in Gustafson 2016) stated that: ... eulachon were present in similar numbers 

in 2013 and 2014. The mean density of all daytime samples in 2013 was 0.021 larvae/m3and in 

2014 it was 0.023 larvae/m3. 

WDFW produced a mean eulachon SSB estimate for the Chehalis River in 2015 of 11 mt, which 

at 11.2 fish per pound equates to a mean estimate of about 272,000 adult spawners (Table 6, 

Langness 2015, as cited in Gustafson 2016). This estimate was developed using methods similar 

to those outlined above for the Columbia River (Langness 2015, as cited in Gustafson 2016). 

The mean eulachon egg and larval outflow from the Chehalis River was estimated at 4.4 billion 

(Table 6, Langness 2015; as cited in Gustafson 2016).

Fraser River—mean total fecundity in Fraser River eulachon ranged from a low of about 

31,200 to a high of about 34,100 when estimated between 1995 and 1998 (Hay et al. 2002). 

Mean relative fecundity (total fecundity divided by female body weight) of Fraser River 

eulachon ranged from a low of 683 eggs/g in 1995 to a high of 898 eggs/g in 1997 (Hay et al. 

2002). There are significant differences in fecundity among years in Fraser River eulachon, 

which are likely related to “significant interannual differences in mean size (length and weight)” 

(Hay et al. 2002, p. 11). 

British Columbia Coastal Rivers—mean fecundity of 58 eulachon from the Kitimat 

River, British Columbia, in 1993 was about 22,900 eggs with a range of 3,242 to 47,798 

(Pedersen et al. 1995, as cited in Willson et al. 2006). Relative fecundity in the Kitimat River 

was calculated at 504 eggs/g female body weight (Pedersen et al. 1995, as cited in Willson et al. 

2006). Based on 5 years of data, mean eulachon fecundity in Kemano River, British Columbia, 

was about 27,000 and ranged 6,744–57,260 eggs. Mean relative fecundity of Kemano River 

eulachon over this 5-year data set was 544 eggs/g female body weight (Lewis et al. 2002, as 

cited in Willson et al. 2006). 

Alaska—mean fecundity of eulachon in the Copper River, Alaska, was estimated at about 

35,520 (range: 12,202–52,722) in 2000 and 36,200 (range: 18,645–62,855) in 2001 (Moffitt et al. 

2002, as cited in Willson et al. 2006). From these data, Moffitt et al. (2002) estimated relative 

fecundity of eulachon from the Copper River in 2000 and 2001 as 790 and 792 eggs/g female 

body weight, respectively. Fecundity in the Twentymile River, Alaska, ranged from as low as 

8,530 to as high as 67,510 and reportedly increased with increasing length, weight, and age (as 

determined by otolith increment analysis) (Spangler 2002, Spangler et al. 2003; as cited in 

Willson et al. 2006).

G. Sex Ratio 

Many studies have reported that sex ratios in eulachon are either biased in favor of males (Smith 

and Saalfeld 1955, Kubik and Wadman 1977, 1978, Franzel and Nelson 1981, Higgins et al. 

1987, Lewis 1997, Lewis et al. 2002, Moffitt et al. 2002, Spangler 2002, Spangler et al. 2003; as 
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cited in Gustafson et al. 2010) or are highly variable depending on time and location of sampling 

(McHugh 1939, Hart and McHugh 1944, Langer et al. 1977, Pedersen et al. 1995; as cited in 

Gustafson et al. 2010). On the other hand, Hay and McCarter (2000, as cited in Gustafson et al. 

2010) and Hay et al. (2002, as cited in Gustafson et al. 2010) report that the ratio of spawning 

male to female eulachon in their gill net samples from the Fraser River in 1995–2002 was 

approximately 1 to 1, with the exception of 1998 when the sex ratio was 1.7 to 1. 

All reports of eulachon sex ratio should be viewed with caution, as proportions of male to female 

eulachon have been reported to vary with fishing gear type, distance upriver, distance from the 

river shoreline, time of the day, and migration time (McHugh 1939, Langer et al. 1977, Moffit et 

al. 2002, Lewis et al. 2002, Spangler 2002, Spangler et al. 2003; as cited in Gustafson et al. 

2010). Langer et al. (1977, p. 33; as cited in Gustafson et al. 2010) reported that “sex ratios 

varied with location, within the duration of the run, and between years in the Nass River.” Lewis 

(1997, as cited in Gustafson et al. 2010) suggested that sex ratios skewed in favor of males may 

be due to longer residence time of male eulachon in freshwater compared to females. Moffit et 

al. (2002, as cited in Gustafson et al. 2010) postulated that as spawning commences, females 

may avoid the riverbank and disperse to the center of the river, thus skewing sex ratios calculated 

from dip net sampling along riverbanks. Spangler (2002, as cited in Gustafson et al. 2010) and 

Spangler et al. (2003, as cited in Gustafson et al. 2010) reported that sampling with different gear 

types (gill nets versus dip nets) resulted in different sex ratios in the Twentymile River, Alaska. 

However, Franzel and Nelson (1981, as cited in Gustafson et al. 2010) reported that fishing gear 

did not significantly change the sex ratio of eulachon captured in the Stikine River, Alaska. 

Mc Hugh (1939, as cited in Gustafson et al. 2010) and Hart and McHugh (1944, as cited in 

Gustafson et al. 2010) reported that the sex ratio varied during the fishing season in 1939 and 

1941 in the Fraser River; males predominated in the early part of the eulachon run, but in the 

latter part females came to predominate. A similar situation may obtain in the Columbia River 

basin, where WDFW and ODFW (2001, p. 15, as cited in Gustafson et al. 2010) stated that 

analysis of sex ratios indicated that “female return timing is skewed later than that of males,” 

although females never appear to dominate. Pedersen et al. (1995, p. 16, as cited in Gustafson et 

al. 2010) reported that earlier studies in the Nass River had found “a changing sex ratio during 

the spawning season,” whereas another study based on daily monitoring had found 55% males 

and 45% females. Lewis et al. (2002, as cited in Gustafson et al. 2010) also reported changing 

sex ratios over the duration of the eulachon run in the Kemano River, British Columbia; 

however, there appeared to be two pulses of female returns, and males rather than females 

appeared to dominate the later part of the run. The proportion of males was also found to 

increase as the run progressed in 1971 on the Nass River (Langer et al. 1977, as cited in 

Gustafson et al. 2010) and at Flag Point Channel on the Copper River in 1998 and 2000–2002 

(Moffit et al. 2002, as cited in Gustafson et al. 2010).
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The overall sex ratio reported by Smith and Saalfeld (1955, as cited in Gustafson et al. 2010) for 

the Columbia River basin was 4.5 males to 1 female. Similarly, Higgins et al. (1987, as cited in 

Gustafson et al. 2010) and Rogers et al. (1990, as cited in Gustafson et al. 2010) found a sex ratio 

of 3.4 males to 1 female in Fraser River samples collected in April 1986 and Rogers et al. (1990,

as cited in Gustafson et al. 2010) reported the ratio to be 5.9 to 1 in 1988. Sex ratios in the early 

1930s in Cowlitz River dip net, Lewis River dip net, and Columbia River gill net samples were 

3.2 to 1, 12.3 to 1, and 6.8 to 1, respectively (Smith and Saalfeld 1955, as cited in Gustafson et 

al. 2010). In 1946 sex ratios in commercial fisheries were 10.5 to 1 in the Cowlitz River and 2.8 

to 1 in the Sandy River, which may reflect the bias in the fishery for the more marketable male 

eulachon (Smith and Saalfeld 1955, as cited in Gustafson et al. 2010). Since males dominate the 

early part of the run in the Columbia River, they are more prevalent in both the sport and 

commercial fisheries, which preferentially target the first fish to return (WDFW and ODFW 

2001, as cited in Gustafson et al. 2010). 

Sex ratio of male to female eulachon in the Kemano River, British Columbia, ranged from 1.1 to 

1 to 10.7 to 1 with a mean of 4.4 to 1 between 1989 and 1997; however, when weighted by fish 

abundance over the duration of the run, the true sex ratio was estimated at 1.6 to 1 (Lewis et al. 

2002, p. 72; as cited in Gustafson et al. 2010). Males predominated in upriver locations in both 

1970 and 1971 in the Nass River (Langer et al. 1977, as cited in Gustafson et al. 2010). 

However, in the Fraser River the proportion of male to female eulachon was independent of the 

distance of upriver capture (along a 31 km gradient) among April 1986 (Higgins et al. 1987, 

Rogers et al. 1990; as cited in Gustafson et al. 2010) and April/May 1988 (Rogers et al. 1990, as 

cited in Gustafson et al. 2010) samples. 

Franzel and Nelson (1981, as cited in Gustafson et al. 2010) found that gill net–sampled 

eulachon in the Stikine River, Alaska, over two years had a sex ratio of males to females of 17.5 

to 1. Eulachon sex ratios on the Copper River, Alaska, and nearby systems were also dominated 

by males in all samples (Moffitt et al. 2002, as cited in Gustafson et al. 2010). The percentages of 

males at Flag Point Channel on the Copper River in 1998, 2000, 2001, and 2002 were 78%, 60%, 

72%, and 69%, respectively. At 60-km Channel on the Copper River in 2002, males represented 

61%–85% of the captured eulachon (Moffit et al. 2002, as cited in Gustafson et al. 2010). On the 

Copper River delta, the percentages of males in 1998 and 2000 were 91% and 66%, respectively, 

in Alaganik Slough and ranged from 82% to 98% in January to February 2001 in Ibeck Creek 

(Moffit et al. 2002, as cited in Gustafson et al. 2010). Eulachon collected in Twentymile River, 

Alaska, from May 15 to June 2, 1976, and from April 29 to June 5, 1977, had a cumulative sex 

ratio of 5 males to 1 female (n = 204) (Kubik and Wadman 1977, as cited in Gustafson et al. 

2010) and 7.4 males to 1 female (n = 408) (Kubik and Wadman 1978, as cited in Gustafson et al. 

2010), respectively. Sampling by dip net in the Twentymile River resulted in male to female 

ratios of 6.7 to 1 in 2000 (n = 394) and 2.1 to 1 in 2001 (n = 2,711) (Spangler 2002, Spangler et 

al. 2003; as cited in Gustafson et al. 2010). Barrett et al. (1984, as cited in Gustafson et al. 2010) 

reported average male to female sex ratios of prespawning eulachon of 1.6 to 1 in late May 1982, 
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1.3 to 1 in early June 1982, 1.2 to 1 in mid-May 1983, and 0.6 to 1 in mid-May and early June 

1983. Spawning and postspawning ratios were higher due to the shorter stream residence time of 

female eulachon (Barrett et al. 1984, as cited in Gustafson et al. 2010). 

Smith and Saalfeld (1955, p. 22, as cited in Gustafson et al. 2010) first hypothesized “that the 

type of spawning of smelt may necessitate an excess of males.” Moffitt et al. (2002, p. 26; as 

cited in Gustafson et al. 2010) postulated that in the case of eulachon, which broadcast-spawn 

eggs and sperm in fast moving rivers, “a large number of males upstream may increase the 

probability of egg fertilization.” Spangler et al. (2003, p. 46; as cited in Gustafson et al. 2010) 

also postulated that a sex ratio skewed in favor of males “may be a key element to successful 

spawning” and that “fertilization would increase with more available milt in the water increasing 

the probability of eggs being fertilized.” Hay and McCarter (2000, p. 23; as cited in Gustafson et 

al. 2010) stated that spawning involves groups of fish and eulachons must closely synchronize 

the timing of spawning between sexes, because the duration of sperm viability in freshwater is 

short, perhaps only minutes. 

H. Spawning 

Eulachon are fundamentally semelparous, although some individuals may spawn twice in a 

lifetime. The frequency of iteroparity might vary among populations—an issue still not 

completely resolved (Hay and McCarter 2000, Lewis et al. 2002, Barraclough 1964, Blackburn 

et al. 1981, Hart and McHugh 1944; as cited in Willson et al. 2006). 

Spawning appears to occur at night (Hay and McCarter 2000, Parente and Snyder 1970, Prince 

Rupert Forest Region 1998, Lewis et al. 2002; as cited in Willson et al. 2006) or possibly 

afternoon (Langer et al. (1977), as cited in Willson et al. 2006). Spawning can occur at various 

depths: up to 25 ft in the Fraser River (Hart and McHugh 1944, as cited in Willson et al. 2006), 

but much less in the Kemano River (0.2-4 m, Lewis et al. 2002, as cited in Willson et al. 2006), 

the Susitna River (1-5 ft, Vincent-Lang and Queral 1984, as cited in Willson et al. 2006). Smith 

and Saalfeld (1955) recovered eggs from depths ranging from 3 in to greater than 20 ft and 

suspected that eggs were present at much greater depths. Egg deposition in the Nass River was 

greater at depths around 3.7-5.2 m than at shallower depths; deeper waters were not sampled 

(Langer et al. 1977, as cited in Willson et al. 2006). The sexes must synchronize their activities

closely, unlike some other group spawners such as herring, because eulachon sperm are said to 

remain viable for only a short time, perhaps only minutes (Hay and McCarter 2000). Males are 

reported to lie next to females, either beside or on top of them, in riffles (Lewis et al. 2002). This 

description differs markedly from that in Langer et al. (1977, as cited in Willson et al. 2006), in 

which males were said to congregate upstream of groups of females, releasing milt 

simultaneously, and females laid eggs as the milt drifted over them; the spent fish then drifted 

downstream. 
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Spawning substrates can range from silt, sand, or gravel to cobble and detritus (Barrett et al. 

1984, Vincent-Lang and Queral 1984; as cited in Willson et al. 2006, and Smith and Saalfeld 

1955), but sand appears to be most common (Langer et al. (1977), Lewis et al. 2002; as cited in 

Willson et al. 2006). It is possible that the substrate favored for the spawning events themselves 

may be different from those where the eggs accumulate (Langer et al. 1977, as cited in Willson

et al. 2006). Egg mortality was higher on silt or organic debris than on sand or gravel (Langer et 

al. 1977, as cited in Willson et al. 2006). 

Spawning rivers may be turbid or clear, but all are thought to have spring freshets, characteristic 

of rivers draining large snow packs or glaciers (Hay and McCarter 2000). Many, but not all, of 

the reported spawning rivers in Alaska are glacial in origin, whereas the more southerly ones are 

not. In general, eulachon would spawn at low water levels before spring freshets (Lewis et al. 

2002, as cited in Willson et al. 2006), although runs in the Fraser River appear to occur at midlevels of river discharge (Langer et al. 1977, as cited in Willson et al. 2006). Most spawning in 

the Susitna River occurred at water velocities of 0.5-2.5 ft/s (Vincent-Lang and Queral 1984, as 

cited in Willson et al. 2006). Spawning sites may vary among years within the same river system 

(Hay and McCarter 2000, Pedersen et al. 1995, Moffitt et al. 2002; as cited in Willson et al. 

2006), and the age distribution of spawners may vary among sites within the same system 

(Moffitt et al. 2002, as cited in Willson et al. 2006). Some small rivers near large runs may have 

occasional spawning populations (Prince Rupert Forest Region 1998, McCarter and Hay 1999; 

as cited in Willson et al. 2006). 

In many rivers, the spawning reach is more or less limited to the part of the river that is 

influenced by tides (Lewis et al. 2002, as cited in Willson et al. 2006). In the Berners Bay 

system, the greatest abundance of eulachon was observed in tidally-influenced reaches, but some 

fish ascended well beyond the tidal influence (Willson et al. 2006). Eulachon are reported to go 

as far as 80 km up the Susitna River (Barrett et al. 1984, Vincent-Lang and Queral 1984; as cited 

in Willson et al. 2006), possibly because of a low gradient (Lewis et al. 2002, Ref. 269). 

Eulachon once ascended more than 160 km in the Columbia River system. There is some 

evidence that water velocity greater than 0.4 m/s begins to limit upstream movements, at least for 

a segment of the eulachon population (Lewis et al. 2002, as cited in Willson et al. 2006). 

Run Timing 

Entry into the spawning rivers appears to be related to water temperature and the occurrence of 

high tides (Ricker et al. 1954, Eulachon Research Council 2000, Prince Rupert Forest Region 

1998, Bishop et al. 1989b, Lewis et al. 2002, WDFW/ODFW 2001, Spangler 2002; as cited in 

Willson et al. 2006). In the Berners Bay rivers in 1996-98, runs appeared to begin during a 

period of higher tides, but not necessarily at the highest tide (>16 ft; M. F. Willson et al. 2006). 

Low levels of river discharge may also contribute to the timing of in-migration (Spangler 2002, 

as cited in Willson et al. 2006). 
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Spawning is reported to occur at temperatures from 4° to 10°C; colder temperatures may stop 

migration (WDFW/ODFW 2001), at least in some rivers. Run timing (as estimated from harvest 

rates) in the Fraser River tended to be earlier in years with somewhat warmer temperatures 

(r = −0.47; Ricker et al. 1954, as cited in Willson et al. 2006). In the Nass River, peak eulachon 

in-migration occurred at temperatures between 0° and 2°C, noticeably colder than in most other 

rivers, and this run is earlier than the eulachon run that occurs at warmer temperatures in the 

Fraser River (Langer et al. 1977, as cited in Willson et al. 2006). In the Stikine River, the 

eulachon run began at temperatures lower than about 2°C, corresponding to the breakup of ice, 

and peaked at about 2 - 3.5°C; some fish were still present at about 8°C (Franzel and Nelson 

1981, as cited in Willson et al. 2006). In the Kemano River, mean water temperature was 3.1°C 

(range 1.1 - 6.5°C) during spawning, 4.1°C (range 2.2 - 5.4°C) during incubation, but 5.9 - 6.0°C 

(range 0.0 - 8.2°C) during larval outmigration (Lewis et al. 2002, as cited in Willson et al. 2006). 

Presumably as a result of temperature dependence and perhaps other factors, eulachon run timing 

does not show a simple latitudinal trend from early in the south to later in the north (Hay and 

McCarter 2000). In the Columbia River, spawning runs typically occur in January, February, and 

March (Hay and McCarter 2000, Eulachon Research Council 2000, WDFW/ODFW 2001; as 

cited in Willson et al. 2006), but small runs (often referred to as “pilot runs,”) can occur as early 

as November or December. The Fraser River runs occur in April (Northcote 1974, in Rogers et 

al. 1990; as cited in Willson et al. 2006) or May, and the nearby Klinaklini River runs occur 

earlier than runs in the Fraser River (Hay and McCarter 2000). Eulachon runs in central and 

northern British Columbia typically occur in late February or March (Hay and McCarter 2000; 

Pedersen et al. 1995, Lewis and O’Connor 2002; as cited in Willson et al. 2006) or late Marchearly April (Eulachon Research Council 2000, Langer et al. 1977, Lewis et al. 2002, Lewis and 

O’Connor 2002; as cited in Willson et al. 2006). Stikine River runs occur in early to mid-April 

(Franzel and Nelson 1981, as cited in Willson et al. 2006). Eulachon runs in rivers on the

Yakutat forelands occur in late February to early April, or even January (Catterson and Lucey 

2002, Lucey 2001; as cited in Willson et al. 2006), markedly earlier than runs in Berners Bay 

rivers (mid-April to early May). The principal run in the Copper River occurred from mid-May 

to late May over four sampling years, with peaks from 23 to 28 May, but timing sometimes 

differed in other streams on the Copper River Delta (Moffitt et al. 2002, as cited in Willson et al. 

2006). Susitna River runs occur in May and June (Vincent-Lang and Queral 1984, as cited in 

Willson et al. 2006), and runs on the Alaska Peninsula occur in June and early July (Warner and 

Shafford 1979, as cited in Willson et al. 2006). 

Some eulachon runs are very reliable from year to year; others occur more sporadically (Stacey 

1995, Hinrichsen 1998, Hay and McCarter 2000, Eulachon Research Council 2000, Smith and 

Saalfeld 1955, as cited in Willson et al. 2006). Some rivers have two eulachon runs per year. For 

example, the Chilkat River has a regular run in May and possibly a smaller, more sporadic one in 

February (Bishop et al. 1989b, Betts 1994; as cited in Willson et al. 2006). The Nass River has 

(or had) a run in March and a smaller one in June (Langer et al. 1977, as cited in Willson et al. 
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2006), and the Dean and Susitna rivers also have two runs (Eulachon Research Council 2000,

Vincent-Lang and Queral 1984, Barrett et al. 1984; as cited in Willson et al. 2006). The 

Twentymile River has pulses of eulachon spawners in May and June (Eulachon Research 

Council 2000, as cited in Willson et al. 2006), and a run duration longer than most others 

reported (Spangler 2002, as cited in Willson et al. 2006). The Copper River system has a small 

but prolonged winter run and a substantial run in May and June; run timing tends to differ among 

the sloughs and river outlets in this area (Moffitt et al. 2002, as cited in Willson et al. 2006). 

Eggs and Larvae 

Eggs are greater than 1 mm in diameter (Hay and McCarter 2000). Eggs are enclosed in a double 

membrane; the outer membrane breaks and turns inside out, making a sticky stalk by which the 

egg adheres to sand grains and small gravels (Hay and McCarter 2000, Hart and McHugh 1944; 

as cited in Willson et al. 2006). Eggs do not adhere to sand immediately but drift downstream for 

a short time; even after adherence, water velocity can move the sand grains farther downstream 

(Lewis et al. 2002, as cited in Willson et al. 2006). Incubation is temperature-dependent, and so 

incubation times can differ among rivers and years.

Eggs can accumulate on the substrate at densities of several to many thousand per square meter 

(Lewis et al. 2002, as cited in Willson et al. 2006). Very large masses of eggs (up to 500 

eggs/ml) sometimes accumulate in areas of low water velocity and may cover many square 

meters (Lewis et al. 2002, as cited in Willson et al. 2006). Survival of eggs during the first 10 

days of incubation in these masses is very low (< 1%). In contrast, early survival of “drifting 

eggs” averaged from 69% to 82% in some years, with as much as 97% survival in some 

locations; however, in another year, average survival was only 9% (up to 23% in some locations; 

Lewis et al. 2002, as cited in Willson et al. 2006). Overall egg-to-larva survival was estimated as 

2.9 - 4.8% in the Kemano River, but less than 1% in the adjacent Wahoo River (Lewis et al. 

2002, as cited in Willson et al. 2006). Egg survival is greatly influenced by salinity: exposure to 

salt water, especially salinity greater than 16 ppt, can be lethal (Farara 1996 cited in Lewis et al. 

2002, as cited as cited in Willson et al. 2006). Major temperature changes also affect survival 

(e.g., a change from 5° to 11°C; Lewis et al. 2002, as cited in Willson et al. 2006). 

Hatching and early development are described briefly by Parente and Snyder 1970, as cited in 

Willson et al. 2006) and DeLacy and Batts (1963), as cited in Willson et al. 2006). The 

“diaphanous” (Smith and Saalfeld 1955) larvae, 4-8 mm long, are immediately carried by 

currents to the sea and may rear in estuaries (Hay and McCarter 2000; Lewis et al. 2002, as cited 

in Willson et al. 2006). Peaks in larval outmigration are thought to occur during periods of 

relatively stable water temperatures and at low light intensities (Spangler 2002, as cited in 

Willson et al. 2006). Out-migrating larvae may be damaged by dredging operations (Dutta 1976, 

as cited in Willson et al. 2006). 
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Young eulachon appear to occupy a variety of depths in the water column. Yolk-sac fry captured 

at the mouth of the Cowlitz River were found near the bottom or at intermediate depths (Smith 

and Saalfeld 1955), but larval eulachon were distributed through the water column in the Fraser 

River estuary (Levings 1980, as cited in Willson et al. 2006). Larvae and young juveniles 

become widely distributed in coastal waters, mostly at depths up to 15 m (Hay and McCarter 

2000) but sometimes as deep as 182 m (Barraclough 1964, as cited in Willson et al. 2006). 

Larvae from southern British Columbia Rivers reach the west coast of Vancouver Island by 

midsummer (Hay et al. 1992). Young eulachon may occur in extensive mixed-species schools 

with young herring and anchovy (Hay et al. 1992). Larvae turn up in ichthyoplankton surveys in 

rivers and bays even when few or no adults have been observed. Thus, larvae found near a 

spawning river may not have originated from that river (Hay and McCarter 2000); larvae might 

originate from undocumented spawning streams or be brought in by oceanic currents. 
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Chapter 2. Listing Factors

1. Threats Assessment

As part of the recovery planning process, threats comprising the listing factors leading to the 

species’ threatened status have been assessed with regard to their geographic extent, severity, life 

stage affected, and responsiveness to management. A threats assessment includes consideration 

of both natural and human threats, which can result from either intentional or unintentional 

actions. The current or potential severity of each threat on the species is affected by a variety of 

characteristics of that threat including the immediate or long-term impact on the species, the 

geographic extent of the threat and the consideration of the specific life stage(s) affected by that 

threat.

An assessment of an individual threat not only includes consideration of its severity, but also the 

responsiveness of that threat to potential management actions and the feasibility of implementing 

those actions. While there may be concern with a particular threat to a species, if there are no 

effective measures that can be implemented to minimize or mitigate that threat, then abatement 

of this threat may not be a high priority recovery action. The ability to implement management 

actions to address a threat and the likelihood that those actions will be effective are critical 

considerations when formulating a strategy for the recovery of a listed species.

An assessment of threats must also recognize the interrelationship among various threats. There 

may be synergistic effects that must be taken into consideration. Evaluation of the individual 

threats in isolation may lead to an underestimate of their impact on eulachon. Attention needs to 

be paid to cumulative impacts of threats or interrelationships between threats in order to ensure 

an accurate assessment.

Threats include human activities or natural events (e.g., fish harvest, volcanoes) that alter key 

physical, biological and/or chemical features and reduce a species’ viability. It is imperative that 

these physical/biological/chemical factors limiting eulachon viability are evaluated, and that the 

causal threats are identified in order to successfully document and implement actions that will 

lead to the recovery of eulachon. In this Recovery Plan, both natural and human-related threats 

are addressed as they relate to section 4(a)(1)(b) of the ESA: A) destruction or modification of 

habitat; B) overutilization for commercial, recreational, scientific, or educational purposes; C) 

disease or predation; D) inadequacy of existing regulatory mechanisms; or E) other natural or 

human factors. Table 2-1 is the BRT’s qualitative threats rankings, and Table 2-2 is the BRT’s 

qualitative threats assessment based on the modal score for each threat in each subpopulation. 

Based on the BRT’s qualitative threats assessment, priority threats (those threats with a 

qualitative threats level of high) facing eulachon are climate change impacts on ocean conditions 

and bycatch in the offshore shrimp trawl fisheries.
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Since the listing of eulachon in 2010, no new significant information, with the possible exception 

of measures to reduce bycatch in the ocean shrimp fisheries, has been discovered or brought to 

our attention regarding the 16 threats identified by the BRT to suggest that these threats have 

changed in an appreciable manner, especially the most pressing threats: climate change impacts 

on ocean conditions, dams/water diversions, eulachon bycatch, climate change impacts on 

freshwater habitats, and predation. In addition, we are not aware of any new data that suggests 

that there are any new threats that have emerged since the 2010 listing that will reduce the 

species’ viability. In 2015 we published a Federal Register notice (80 FR 6695) regarding the 

initiation of a 5-year status review for eulachon; we received no new information or data on 

eulachon. 

Table 2-1. Eulachon qualitative threats rankings by subpopulation23, and ESA Section 

4(a)(1)(b) Factors. 

 Subpopulation

Threats Klamath Columbia Fraser BC §4 

Factor

 Ranking

Climate change impacts on ocean conditions 1 1 1 1 A

Dams/water diversions 2 4 8 11 A

Eulachon bycatch 3 2 2 2 E

Climate change impacts on freshwater 

habitats 

4 3 4 4 A

Predation 5 7 3 3 C

Water quality 6 5 5 8 A

Catastrophic events 7 8 10 5 A

Disease 8 11 11 7 C

Competition 9 12 12 9 E

Shoreline construction 10 10 9 6 A

Tribal/First Nations fisheries 11 14 13 10 B

Nonindigenous species 12 15 15 13 E

Recreational harvest 13 13 14 14 B

Scientific monitoring - 16 16 15 B

Commercial harvest - 9 6 - B

Dredging - 6 7 12 A

(-) no ranking due to insufficient data. 

 

23 For a description of the qualitative threats assessment see Gustafson et al. 2010, p. 166-170. 
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Table 2-2. Eulachon Level of Threat Severity in each Subpopulation.

Subpopulation

Threats Klamath Columbia Fraser BC

Severity

Climate change impacts on ocean conditions high high high high

Dams /water diversions moderate moderate very low very low

Eulachon bycatch moderate high moderate high

Climate change impacts on freshwater habitat moderate moderate moderate moderate

Predation moderate moderate moderate moderate

Water quality moderate moderate moderate low

Catastrophic events very low low very low low

Disease very low very low very low very low

Competition low low low low

Shoreline construction very low moderate moderate low

Tribal/First Nations fisheries very low very low very low low

Non-indigenous species very low very low very low very low

Recreational harvest very low low very low very low

Commercial harvest very low low low very low

Scientific monitoring very low very low very low very low

Dredging very low moderate low very low

Threats 

The following sections provide a summary on the threats to eulachon with respect to the five 

ESA section 4(a)(1)(b) factors, and an assessment of the threat from a recovery perspective. The 

BRT Rankings are from Gustafson et al. 2010; the BRT Threats Severity assessment is the level 

of threat severity based on the BRTs modal score for each threat in each subpopulation, threat 

levels are rated as Very Low, Low, Moderate, High, or Very High (Gustafson et al. 2010). 

A. Present or Threatened Destruction, Modification, or Curtailment of Habitat or 

Range 

Threat—Climate Change Impacts on Ocean Conditions

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 1 1 1 1

BRT Threat Severity High High High High

Listing Factor A A A A

Threat—Climate Change Impacts on Freshwater Habitats

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 4 3 4 4

BRT Threat Severity Moderate Moderate Moderate Moderate

Listing Factor A A A A
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Environmental conditions in both marine and fresh waters inhabited by eulachon are influenced, 

in large part, by two ocean-basin scale drivers, the Pacific Decadal Oscillation (PDO) (Mantua et 

al. 1997) and the El Niño Southern Oscillation Index (ENSO). 

Climate change impacts on ocean conditions, i.e., as measured by large-scale spatial and 

temporal shifts in oceanic-atmospheric patterns in the northeast Pacific Ocean associated with 

both natural climate variability and anthropogenic-forced climate change, is likely the principal 

threat to eulachon, as it is the one phenomenon that correlates with the recent species-wide 

declines in abundance. While the specific characteristics that provide favorable marine 

conditions for eulachon in the northeast Pacific Ocean are unknown, the available information 

suggests that there is a link between the (PDO) (Gustafson et al. 2010), as well as other marine 

indices such as the ENSO, the Oceanic Niño Index (ONI), and the Northern Oscillation Index 

(NOI), and eulachon survival, abundance, and recruitment potential. One hypothesis is that coolphase PDO cycles are associated with greater primary and secondary productivity in the northern 

California Current (Figure 2-1) that provide abundant food resources for multiple age classes, 

especially larval eulachon entering the marine environment.

Figure 2-1. A working hypothesis on how changes in the Pacific Decadal Oscillation affect 

productivity in the northern California Current Peterson et al. (2013).

Likely changes in temperature, precipitation, wind patterns, and sea level height have profound 

implications for survival of eulachon, in both their freshwater and marine habitats. Recent 

descriptions of expected changes in Pacific Northwest climate that are relevant to eulachon

include Elsner et al. (2009), Mantua et al. (2009), Mote and Salathe (2009), Salathe et al. (2009), 

and Gustafson et al. (2010). Reviews of the effects of climate change in the Columbia River 

basin include ISAB (2007), Hixon et al. (2010), Dalton et al. (2013), and NMFS (2014). 
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The following is a summary of expected climate change-related effects on eulachon and their 

habitats derived from the above sources.

Freshwater Environments

Climate records show that the Pacific Northwest has warmed about .07°C since 1900, or about 

50% more than the global average warming over the same period (Dalton et al. 2013). The 

warming rate for the Pacific Northwest over the next century is projected to be in the range of 

0.1°C to 0.6°C per decade. While total precipitation changes are predicted to be minor (+1% to 

2%), increasing air temperature will alter the snow pack, stream flow timing and volume, and 

water temperature in the Columbia Basin. Climate scientists predict the following physical 

changes to rivers and streams in the Columbia River Basin:

• Warmer temperatures will result in more precipitation falling as rain rather than 

snow.

• Snow pack will diminish, water temperatures will increase, and stream flow 

volume and timing will be altered.

Estuarine and Plume Environments

Climate change will also affect eulachon in the estuarine and plume environments. In the estuary, 

eulachon would be primarily affected by increased in water temperatures, flow-related changes, 

altered phytoplankton and zooplankton prey, and increased predation. Eulachon may be affected 

by habitat changes in the plume environment due to flow- or sediment-related changes; however, 

use of plume habitat by eulachon remains poorly understood. Effects of climate change on 

eulachon in the estuary and plume may include the following:

• Higher winter freshwater flows and higher sea levels may increase sediment 

deposition in the plume, possibly reducing the quality of rearing habitat.

• Lower freshwater flows in late spring and summer may lead to upstream 

extension of the salt wedge, possibly influencing the distribution of eulachon prey 

and predators.

• Increased temperature of freshwater inflows and seasonal expansion of freshwater 

habitats may extend the range of non-native, warm-water species that are 

normally found only in freshwater.

In all of these cases, the specific effects on eulachon abundance, productivity, spatial distribution 

and diversity are poorly understood.
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Marine Environments

Effects of climate change in marine environments include: increased ocean temperature, 

increased stratification of the water column, changes in intensity and timing of coastal upwelling, 

and ocean acidification. Hypotheses differ regarding whether coastal upwelling will decrease or 

intensify, but even if it intensifies, the increased stratification of the water column may reduce 

the ability of upwelling to bring nutrient-rich water to the surface. There are also indications in 

climate models that future conditions in the North Pacific region will trend toward conditions 

that are typical of the warm phases of the PDO, but the models in general do not reliably 

reproduce the oscillation patterns. Hypoxic conditions observed along the continental shelf in 

recent years appear to be related to shifts in upwelling and wind patterns that may be related to 

climate change.

Climate-related changes in the marine environment are expected to alter primary and secondary 

productivity, the structure of marine communities, and in turn, the growth, productivity, and 

survival of eulachon, although the degree of impact on eulachon is currently poorly understood. 

A mismatch between larval survival (because of earlier peak spring freshwater flows and 

decreased incubation period) and altered upwelling may reduce marine survival rates.

Ocean warming also may change migration patterns, increasing distances to feeding areas. 

Rising atmospheric carbon dioxide concentrations drive changes in seawater chemistry, 

increasing the acidification of seawater and thus reducing the availability of carbonate for shellforming invertebrates. This process of acidification is under way, has been well documented 

along the Pacific coast of the United States, and is predicted to accelerate with increasing 

greenhouse gas emissions.

Ocean acidification has the potential to reduce survival of many marine organisms, including 

eulachon. However, because there is currently a paucity of research directly related to the effects 

of ocean acidification on salmon and their prey, potential effects are uncertain. Laboratory 

studies on prey taxa have generally indicated negative effects of increased acidification, but how 

this translates to the population dynamics of eulachon prey and the survival of eulachon is

uncertain. Modeling studies that explore the ecological impacts of ocean acidification and other 

impacts of climate change concluded that salmon landings in the Pacific Northwest and Alaska 

are likely to be reduced.

Conclusion

Based on this information, the threat occurs at a high severity and there is a high level of 

uncertainty. Thus, the relative impact to recovery is ranked high.
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Threat—Water Quality

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 8 5 5 8

BRT Threat Severity Moderate Moderate Moderate Low

Listing Factor A A A A

Water quality is divided here into two groups: (1) as the chemical, physical, biological, and 

radiological characteristics largely determined by climatic, geomorphological and geochemical 

conditions; and (2) anthropogenic, largely affected by man, directly or indirectly, via the 

introduction of substances, natural or synthetic, or energy which result in detrimental effects on 

aquatic ecosystems from industrial activities, such as the manufacture of computer, electrical, 

and optical products; manufacture of automobiles, trucks, trains, ships; dam construction; 

urbanization; and agricultural activities, such as crop and animal production, mining and 

quarrying, and forestry.

The following is a summary of expected water quality-related effects on eulachon based on 

Gustafson et al. (2010).

General Contaminants— Contaminants enter fresh and marine waters and sediments 

from numerous sources such as atmospheric transport and deposition, ocean current transport, 

and terrestrial runoff, but are typically concentrated near populated areas of high human activity 

and industrialization. The high lipid content of eulachon suggests they are susceptible to 

absorption of lipophilic organic contaminants (Higgins et al. 1987, Pickard and Marmorek 2007; 

as cited in Gustafson et al. 2010). Contaminants considered of most concern include: 1) synthetic 

chlorinated organic chemicals, such as hexachlorobenzene, DDTs, and the polychlorinated 

biphenyls (PCBs); 2) polycyclic aromatic hydrocarbons (PAHs) from petroleum and creosoted 

pilings; 3) dioxins and a host of other organic compounds; 4) metals such as mercury, arsenic, 

and lead; and 5) endocrine-disrupting compounds and new toxics like PBDE (polybrominated 

diphenyl ether). 

The Environmental Protection Agency (EPA 2002; as cited in Gustafson et al. 2010) examined 

contaminants in fish, including whole eulachon, from the Columbia River in 1996–1998. In 

general, these eulachon had some of the lowest levels of organic chemicals of all the fishes tested 

but had the highest average concentrations of arsenic (0.89 μg/g whole body weight) and lead 

(0.50 μg/g). 

Hall (1976, p. 45; as cited in Gustafson et al. 2010) reviewed water quality and sources of 

pollution in the lower Fraser River and stated that: 

There appear to be two main water quality problems in the lower Fraser, both apparently 

attributable to the urban-industrial complex of metropolitan Vancouver, namely 

pathogens and trace metals. ... Potential problems are apparent regarding toxic 

substances such as trace metals. Concentrations are not high enough to be acutely toxic to 
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fish but the sporadic occurrence of higher concentrations of trace metals such as lead, 

mercury, and zinc in the lower reaches of the river and accumulations in sediments give 

some cause for concern, especially since these substances are not biodegradable and 

bioamplification through food chain concentration or direct absorption by the organism 

cannot be ignored in the sensitive estuarine areas of the lower Fraser. 

Types and sources of contaminants in the lower Fraser River consist of insecticides and 

herbicides used in agricultural production; wood preservatives associated with the lumber 

industry (e.g., chromium, copper, arsenic, chlorinated phenols, dioxins, polynuclear aromatic 

hydrocarbons, phenolics, and creosote); leachates from landfills; a wide range of contaminants in 

stormwater discharge; industrial effluents associated with metal, cement, forest products, and 

food industries; and municipal effluents (Birtwell et al. 1988, as cited in Gustafson et al. 2010). 

Temperature—Smith and Saalfeld (1955) reported that eulachon are present in the 

Columbia River when water temperatures are between 2°C and 10°C and delay migration into 

spawning tributaries until temperatures are above about 4.4°C (WDFW/ODFW 2001). When 

river temperatures vary above or below normal, eulachon may fail to spawn in normal areas, 

delay spawning, or migrate into other tributaries (Smith and Saalfeld 1955, WDFW/ODFW 

2001). 

Snyder (1970, as cited in Gustafson et al. 2010) reported on studies in 1968 and 1969 that 

examined the temperature tolerance of adult eulachon and eggs taken from the Columbia and 

Cowlitz rivers and found that eggs were more tolerant to temperature increases than were adults. 

Increases of 2.8°C and 5.6°C killed 50% and 100% of adult smelt, respectively, within 8 days. 

Even when exposed to temperatures elevated by 9°C for a single hour, 50% of adult eulachon 

were dead after 32 hours. When placed in water 3.9°C above river temperatures, females failed 

to deposit eggs (Snyder 1970, as cited in Gustafson et al. 2010). Slightly different results were 

reported by Blahm and McConnell (1971, as cited in Gustafson et al. 2010) on effects of 

increased temperature on eulachon collected from the Cowlitz River in 1968 and 1969. They 

reported that the incipient lethal temperature for eulachon acclimated to 5°C was 11°C. All 

eulachon exposed to 11°C were dead after 8 days exposure. When eulachon had been acclimated 

to 10°C, a sudden exposure to 18°C for one hour followed by return to 10°C resulted in at least 

50% mortality within 50 hours (Blahm and McConnell 1971, as cited in Gustafson et al. 2010). 

All female fish exposed to elevated temperatures failed to deposit eggs within 50 hours, in 

contrast to female eulachon in control conditions that successfully deposited eggs (Snyder and 

Blahm 1971, as cited in Gustafson et al. 2010). 

When evaluating temperature criteria for Washington’s water quality standards, Hicks (2000, p. 

99; as cited in Gustafson et al. 2010) stated that: 

The studies on smelt indicate they have a lower lethal temperature limit than do the 

salmonids and a lower optimum temperature preferendum...given that adult spawners 
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and outgoing juveniles may be in fresh waters as late as March to mid-April, and their 

temperature requirements may be stricter than most salmonids, the protection of smelt is 

an important consideration in setting water quality standards. In waters supporting smelt, 

it is recommended that the 7-day average of the daily maximum temperatures not exceed 

12–14°C prior to May 1, with no single daily maximum temperature greater than 16°C. 

In 2014 (NMFS 2014), NMFS evaluated the effects of the Federal Columbia River Power 

System (FCRPS) on eulachon and their habitat and concluded that:

[the FCRPS] will continue to alter the hydrograph of the Columbia River in a manner that 

will continue to alter water quality (reduced spring turbidity levels), water quantity 

(seasonal changes in flows and consumptive losses resulting from use of stored water for 

agricultural, industrial, or municipal purposes), water temperatures, and water velocity 

(reduced spring flows and increased cross-sectional areas of the river channel). 

In general, flow regulation has increased minimum winter temperatures when adult 

eulachon are migrating through and spawning in the Columbia River and has reduced 

average spring temperatures compared to an undeveloped system. These patterns are due 

to the increased thermal inertia of large volumes of stored water, increased solar radiation 

over the larger surface area of the reservoirs, and altered seasonal flow regimes. 

Temperatures in the reach below Bonneville Dam are also affected by tidal exchange 

with the ocean and by tributaries to the estuary (especially the Lewis, Cowlitz, 

Elochoman, and Grays rivers in Washington and the Willamette and Clatskanie rivers 

and several smaller streams in Oregon). 

Hicks (2000) evaluated proposed water quality standards for temperature in Washington 

State proposed for the protection of salmonids and char and their protectiveness for other 

indigenous fish species in Washington State, including eulachon. Hicks identified a 

temperature range of 2°C to 10°C for spawning and migration; for successful egg 

deposition, Hicks noted water temperatures of less than 13°C were protective; and Hicks 

identified 18°C as rapidly lethal to adult eulachon. 

Water temperatures measured at tidal freshwater sites, in the mixing zone, and at marine 

sites near the mouth of the estuary ranged from about 4°C to 10°C during January 

through April in 2003 to 2006. These data indicate that temperatures eulachon encounter 

within the Columbia River estuary during the months of January through April do not 

exceed the range needed for the conservation of the species. 

The months of January through April are considered the peak activity level for all 

eulachon life stages. To look at water temperature effects to eulachon during the nonpeak activity level of May through July, we used the U.S. Geological Survey (USGS) 

water temperature data for the Columbia River, and the EPA Region 10 Guidance for 

Pacific Northwest State and Tribal Temperature Water Quality Standards (USEPA 2003). 
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First, we looked at water temperatures measured by the USGS between May 30, 2013 

through July 30, 2013 at Washougal, WA, RM 121; during this period, water 

temperatures ≥16°C were first reported on June 6, 2013, continuing through the end of 

July with temperatures ≥18°C reported on June 18, 2013, and water temperatures 

reaching a high 22.1°C on July 27, 2013 (USGS 2013). Second, we looked at water 

temperatures measured by the USGS between May 30, 1998 through July 30, 1998 

(available time series), at Wauna, OR, RM 42. During this period, water temperatures 

≥16°C were first reported on June 9, 1998, continuing through the end of July with 

temperatures ≥18°C reported on June 24, 1998, and water temperatures reaching a high 

of 23.4°C on July 29, 1998 (USGS 2013). The range of temperatures ≥16°C overlap with 

the presence of all eulachon life stages (non-peak activity level) in the Columbia River. 

As with salmon and steelhead, eulachon exposed to temperatures ≥16°C, measured as the 

7-day average of the daily maximum, are likely to be subjected to adverse water quality 

conditions with an increased risk of reduced egg viability, disease, reduced growth, and 

mortality (USEPA 2003). 

Conclusion 

Based on this information, the threat occurs at a moderate severity and there is a medium-to-high 

level of uncertainty. Thus, the relative impact to recovery is ranked moderate. 

Threat—Catastrophic Events

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 7 8 10 5

BRT Threat Severity Very Low Low Very Low Low

Listing Factor A A A A

Catastrophic events, such as volcanic eruptions and large-scale wildfires, can, depending on the 

nature, magnitude, extent, and duration of the event, increase a species’ extinction risk. 

Emmett et al. (1990, as cited in Gustafson et al. 2010) documented the effects of the dramatic 

increase in turbidity in the Columbia River on fishes in the estuary following the May 18, 1980 

eruption of Mount St. Helens, which resulted in introduction of large quantities of volcanic ash 

and sediment into the Columbia River. Although hampered by the absence of long-term preeruption data, Emmett et al. (1990, as cited in Gustafson et al. 2010) showed that densities of 

benthic invertebrates, particularly amphipods, were significantly reduced and feeding habits and 

distribution of estuarine fishes were altered following the eruption.

Conclusion 

Based on this information, the threat occurs at a low to very low severity and there is a high level 

of uncertainty. Thus, the relative impact to recovery is ranked low. 
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Threat—Shoreline Construction

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 7 8 10 5

BRT Threat Severity Very Low Moderate Moderate Low

Listing Factor A A A A

Adverse effects of shoreline construction to natural resources include: reduced or degraded 

habitat for breeding, spawning, feeding, growing, and thermoregulation for a variety of fish and 

wildlife species; impaired movement of organisms between aquatic and terrestrial habitat; altered 

physical structure of the water's edge, with resultant changes to hydrology; local changes in 

water quality, including changes to temperature, nutrients and contaminants; and increased 

erosion of the adjacent natural shorelines and scouring in front of the structure. Together these 

factors may reduce the amount and quality of spawning and rearing habitats available to 

eulachon, limit access to other historically productive habitats, and degraded watershed 

processes and functions that once created healthy ecosystems for eulachon production. 

The following is a summary of shoreline construction-related effects on eulachon based on 

Gustafson et al. (2010).

Columbia River—Estuarine habitat in the Columbia River has been modified through 

“shoreline armoring and construction of structures over water, channel dredging and removal of 

large woody debris, channelization by pile dikes, and other structures” (Bottom et al. 2005, p. 18; 

as cited in Gustafson et al. 2010). Thomas (1983, as cited in Gustafson et al. 2010) estimated that 

estuarine acreage at the time of his study was only about 76% of the acreage of the estuary in 

1870. This reduction was largely the result of dike and levee construction. Approximately 43% 

of tidal marshes and 77% of tidal swamps in the Columbia River estuary were estimated to have 

been lost since 1870 (Thomas 1983, as cited in Gustafson et al. 2010). Sherwood et al. (1990, p. 

299; as cited in Gustafson et al. 2010) also reviewed historical changes in the Columbia River 

estuary and found that “large changes in the morphology of the estuary have been caused by 

navigational improvements (jetties, dredged channels, and pile dikes) and by the diking and 

filling of much of the wetland area.” Sherwood et al. (1990, as cited in Gustafson et al. 2010) 

suggested that the greatest cause of change in the morphology of the Columbia River estuary was 

due to construction of permeable pile dikes and jetties, particularly jetties at the mouth of the 

river. LCFRB (2004a, p. A-157; as cited in Gustafson et al. 2010) reported that: 

Artificial channel confinement has altered river discharge and hydrology, as well as 

disconnected the [Columbia] river from much of its floodplain. ... Additionally, channel 

manipulations for transportation or development have also had substantial influence on 

river discharge and hydrologic processes in the river. 

Bottom et al. (2005, p. xxii; as cited in Gustafson et al. 2010) provided a chronology of changes 

in the Columbia River estuary and stated that: 
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The productive capacity of the estuary has likely declined over the past century through 

the combined effects of diking and filling of shallow-water habitats.... Loss of 

approximately 65% of the tidal marshes and swamps that existed in the estuary prior to 

1870, combined with the loss of 12% of deep-water area, has contributed to a 12–20% 

reduction in the estuary’s tidal prism. 

Columbia River Tributaries—The LCFRB (2004a, p. E-89; as cited in Gustafson et al. 

2010) observed that “the mainstem Cowlitz below Mayfield Dam has been heavily altered due to 

adjacent land uses including agriculture, rural residential development, transportation corridors, 

urbanization, and industry.” The LCFRB (2004a, p. E-30; as cited in Gustafson et al. 2010) also 

reported that “the lower 20 miles of the Cowlitz has experienced severe loss of floodplain 

connectivity due to dikes, riprap, or deposited dredge spoils originating from the Mount St. 

Helens eruption.” Major population centers in the lower Cowlitz River basin with their 

associated industrial and residential development include the towns of Castle Rock, Longview, 

and Kelso (LCFRB 2004a, as cited in Gustafson et al. 2010). 

The only urban area in the Kalama River basin is the City of Kalama, located near the river’s 

mouth where dikes have been constructed in the historical floodplain to protect nearby roads and 

industrial developments (Wade 2000a, LCFRB 2004a; as cited in Gustafson et al. 2010). Future 

development is likely to be concentrated along the lower mainstem Kalama River, where 

increasing residential development has also occurred in recent years (LCFRB 2004a, as cited in 

Gustafson et al. 2010). 

Much of the lower mainstem Lewis River is also “disconnected from its floodplain by dikes and 

levees” (LCFRB 2004a, p. G-55; as cited in Gustafson et al. 2010) and “the largest urban 

population center, the City of Woodland, lies near the mouth of the river” (Wade 2000a, p. 23; as 

cited in Gustafson et al. 2010). According to (LCFRB 2004a, p. G-87; as cited in Gustafson et al. 

2010), “the mainstem Lewis below Merwin Dam has been heavily altered due to adjacent land 

uses including agriculture, residential development, transportation corridors, and industry.” 

British Columbia—Pickard and Marmorek (2007, as cited in Gustafson et al. 2010) 

reported that results of a DFO workshop to determine research priorities for eulachon indicated 

that shoreline construction in the form of roads, bridges, dikes, piers, wharfs, and so forth may 

have an impact on eulachon in the Skeena, Kitimat, Kemano, Fraser, and Columbia rivers. 

According to Pickard and Marmorek (2007, p. 14; as cited in Gustafson et al. 2010): 

There is evidence of change in the habitat in developed rivers such as the Fraser and 

Kitimat. These changes include the loss of side channels, loss of habitat 

complexity/diversity, and increase in velocity. These habitat changes are thought to affect 

eulachon, however the magnitude of the effect is not clear. 

Pickard and Marmorek (2007, as cited in Gustafson et al. 2010) also suggested that an increase in 

river velocities likely would result in eggs and larvae being rapidly washed downstream, where 
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they may encounter high salinities at an early age. The fate of eggs and larvae that may be 

prematurely washed out to sea is unknown. 

The largest city in British Columbia, Vancouver, together with all of its associated industrial and 

urban development, abuts the Fraser River estuary (Birtwell et al. 1988, as cited in Gustafson et 

al. 2010). Moody (2008) indicated that an extensive system of dikes was constructed in the lower 

Fraser River following the 1948 flood. According to Plate (2009, p. 3 and p. iii; as cited in 

Gustafson et al. 2010), recent plans to construct “a new 10-lane Port Mann Bridge [over the 

Fraser River] represents a major addition to shoreline and in-river construction on the lower 

Fraser River” and is of concern because “eulachon spawn directly beneath the [current] Port 

Mann Bridge pillars and in the close upstream vicinity of the bridge, and as expected eulachon 

use all channels under the bridge for migration to upstream areas.” 

Conclusion 

Based on this information, the threat occurs at a very low to moderate severity and there is a 

medium level of uncertainty. Thus, the relative impact to recovery is ranked moderate. 

Threat—Dams/Water Diversions

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 2 4 8 11

BRT Threat Severity Moderate Moderate Very Low Very Low

Listing Factor A A A A

Both individually and cumulatively, dams fundamentally transform river ecosystems in several 

ways: (a) They alter the downstream flux of water and sediment, which modifies biogeochemical 

cycles as well as the structure and dynamics of aquatic and riparian habitats; (b) they change 

water temperatures, which influences organismal bioenergetics and vital rates; (c) and they 

create barriers to upstream–downstream movement of organisms and nutrients, which hinders 

biotic exchange. These fundamental alterations have significant ecological ramifications at a 

range of spatial and temporal scales (Poff and Hart 2002). 

Klamath River and Trinity Rivers—The six hydroelectric dams on the Klamath and 

Trinity Rivers, as well as associated irrigation withdrawals in the upper Klamath River basin, 

have shifted the spring peak flow of the lower Klamath River from its historical peak in April to 

its current peak in March, one full month earlier (NRC 2004, as cited in Gustafson et al. 2010). 

Columbia River Basin—In the Columbia River Basin, there are more than 470 dams, 

with more than 150 hydroelectric projects throughout the basin, and a vast network of dams and 

irrigation canals. These dams and water control structures have significantly altered the natural 

hydrologic pattern of the Columbia River (Sherwood et al. 1990, Bottom et al. 2005, as cited in 

Gustafson et al. 2010). Development of a large-scale hydropower system in the Columbia River 

Basin has changed seasonal flow rates, reduced sediment transport, and discharge (i.e., the rate 
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of flow) to the nearshore ocean environment (ISAB 2000). Physical changes in the estuary and 

regulation of river flow have also altered the dynamics of seawater intrusion, circulation, and 

sedimentation processes in the estuary, and have had large ecosystem-level consequences (ISAB 

2000).

Since the development of the Canadian and Federal Columbia River Power System (FCRPS)

storage projects in the upper Columbia basin (1940s through 1970s), water is store during spring 

and released for power production and flood control during winter, shifting the annual 

hydrograph. Water withdrawals and flow regulation have reduced the Columbia River’s average 

flow, altered its seasonality, and altered sedimentation processes and seasonal turbidity events, 

e.g., estuary turbidity maximum (Simenstad et al. 1982, 1990; Sherwood et al. 1990; NRC 1996; 

Weitkamp 1994, as cited in NMFS 2008a). Water withdrawals and flow regulation have 

significantly affected the timing, magnitude and duration of the spring freshet through the 

Columbia River estuary such that they are about one-half of the pre-development levels (NMFS 

2008a), all of which are important for eulachon adult, larval, and egg life stages.

In the Columbia River estuary, both the quantity and timing of instream flows have changed 

from historical conditions (Fresh et al. 2005). Jay and Naik (2002) reported a 16% reduction of 

annual mean flow over the past 100 years and a 44% reduction in spring freshet flows. Jay and 

Naik (2002) also reported a shift in flow patterns in the Columbia to 14 to 30 days earlier in the 

year, meaning that spring freshets are occurring earlier in the seasons. In addition, the 

interception and use of spring freshets (for irrigation, reservoir storage, etc.) has caused increased 

flows during other seasons (Fresh et al. 2005). It is unknown what effect these changes in 

hydrology may have on eulachon habitat

The Columbia River plume is a freshwater/saltwater interface where freshwater exiting the 

Columbia River meets and rises above the denser saltwater of the Pacific Ocean. The plume’s 

location varies seasonally with discharge, prevailing near-shore winds, and ocean currents. In 

summer, the plume extends far to the south and offshore along the Oregon coast. During the 

winter, it shifts northward and inshore along the Washington coast. Strong density gradients 

between ocean and plume waters create “fronts” (i.e., interfaces or transition zones) where 

organic matter and organisms are concentrated (Fresh et al. 2005, as cited in Gustafson et al. 

2010). Water management in the Columbia basin has reduced the size, shape and intensity of the 

plume. 

NMFS (2014) evaluated the effects of the FCRPS on eulachon and their habitat and concluded 

that:

[The FCRPS] will continue to alter the hydrograph of the Columbia River in a manner 

that increases flows during the fall–winter period by 8.9%, 12.4%, 15.1%, 27%, 19.7%, 

and 10.2%, respectively, during the months of October through March, and diminishes 

flows during the spring–summer period by 0.7%, 10.4%, 12.7%, 10.4%, 2.5%, and 1.4%, 
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respectively, during the months of April through September, relative to pre-development 

of the dams in the basin. These operational effects on the hydrograph have the potential 

to affect eulachon spawning production, egg incubation, and larval and juvenile growth, 

development, and survival in the estuary–plume environment. 

The fraction of the hydrograph of the Columbia River that is due to the operations of the 

FCRPS is approximately 30% (BPA et al. 2001) of the overall change in the hydrograph 

under the 2008/2010 RPA. NOAA Fisheries calculated these net changes in flows based 

on the HYDSIM model simulated-mean monthly Columbia River flows at Bonneville 

Dam for the water years 1929–1978 (USBR 1999, as cited in NOAA 2015; BPA et al. 

2001). 

Although habitat–related effects to eulachon as a result of the continued operations of the 

FCRPS has the potential to affect eulachon spawning behavior; egg viability; and larvae 

and juvenile growth, development, and survival, the principal habitat-related effects to 

eulachon as a result of the continued operations of the FCRPS are the hydrological effects 

on the estuary–plume environment, which is utilized by eulachon larvae and juveniles for 

rearing and maturation. Continued operations of the FCRPS, especially during the April 

through July period, a period that coincides with eulachon larval ocean entry and 

residence timing, is likely to affect the chemical and physical processes of the estuary–

plume environment (NMFS 2008a, as cited in NOAA 2015), and therefore may have 

negative impacts on marine survival of eulachon larvae and juveniles during the 

freshwater–ocean transition period.

The extent to which freshwater-derived dissolved and particulate matter to the ocean may 

influence the survival of eulachon larvae during the freshwater–ocean transition period is 

unclear. However, Gustafson et al. (2010) noted that variable year-class strength in 

marine fishes with pelagic larvae is dependent on survival of larvae prior to recruitment 

and is driven by match-mismatch of larvae and their planktonic food supply, 

oceanographic transport mechanisms, and variable environmental ocean conditions. 

Based on this link between planktonic food supply, environmental ocean conditions, and 

eulachon larvae, decreased freshwater inputs during the months of April through 

September are likely to affect the chemical and physical processes of the estuary–plume 

environment, and thus planktonic food supply, as a result of water management 

operations via the FCRPS.

In a ten-year study on the biotic and abiotic factors influencing forage fish and pelagic 

nekton communities in the Columbia River plume throughout the upwelling season, Litz 

et al. (2013, as cited in NMFS 2014) examined the assemblages of forage fish, predator 

fish, and other pelagic nekton in coastal waters associated with the Columbia River 
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plume. They found that resident euryhaline24 forage fish species, such as smelts, showed 

a high affinity for inshore habitat and the lower salinity plume during spring. Overall, 

their study revealed that temporal dynamics in abundance and community composition 

were associated with seasonal abiotic phenomenon, but not interannual, large-scale 

oceanographic processes. Forage fish assemblages differed seasonally and spatially from 

the assemblages of major piscivorous predators, suggesting a potential role of the plume 

as refuge for forage fish.

These studies highlight the connection between river-derived nutrients, coastalupwelling, chemical and physical process in the estuary–plume environment, primary 

productivity, and the importance of the estuary–plume environment to eulachon, 

especially eulachon larvae and juveniles. In the absence of direct data on the link between 

decreases in freshwater inputs into the estuary-plume environment and effects on 

eulachon larvae and juveniles to assess the significance of effects, we determined, based 

on available information, that the magnitude of reduced freshwater delivery to the 

estuary–plume environment via water management operations under the FCRPS during 

the months of April through September (0.7%, 10.4%, 12.7%, 10.4%, 2.5%, and 1.4% 

reduction, respectively is likely to be of a magnitude, duration, frequency, and spatial 

extent sufficient to adversely affect primary productivity such that eulachon larvae and 

juveniles in the estuary-plume environment will be subjected to decreases in food 

availability and quality (caloric content), which is likely to reduce the species’ fitness and 

survival potential.

Bonneville Dam (RKM 235) also impedes migration of eulachon to historical spawning 

habitat above the dam in the Hood River and possibly the Klickitat River (Smith and 

Saalfeld 1955, WDFW and ODFW 2008; as cited in Gustafson et al. 2010). Eulachon 

reportedly are unable to ascend fish ladders designed for Pacific salmon (LCFRB 2004a, 

as cited in Gustafson et al. 2010).

Overall, the available evidence indicates that shifts in the timing, magnitude, and duration 

of the hydrograph of the Columbia River via water management operations are likely to 

continue to affect the Columbia River subpopulation of eulachon. These effects will 

disproportionately manifest on eulachon larvae compared to habitat–related effects on 

adult and juvenile eulachon that reside in the estuary–plume environment, especially 

during the months of May through July when freshwater inputs to the estuary–plume are 

significantly diminished, which in turn may affect phytoplankton production—the 

primary food resource for eulachon larvae in the estuary–plume. 

 

24 Species that are able to live in waters of a wide range of salinity.
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Columbia River Tributaries—In the Cowlitz River watershed, there are two major 

dams on the mainstem Cowlitz River: Mayfield Dam at RKM 83.7 forms Mayfield Lake 

and Mossyrock Dam at RKM 104.6 forms Riffe Lake (Wade 2000b, as cited in Gustafson 

et al. 2010). These dams and other run-of-river dams in the hydropower system largely 

control flow in the mainstem Cowlitz River. Following the eruption of Mount St. Helens 

in 1980, the USACE constructed a sediment retention structure (SRS) on the North Fork 

Toutle “to prevent the continuation of severe downstream sedimentation of stream 

channels, which created flood conveyance, transportation, and habitat degradation 

concerns” (LCFRB 2004a, p. E-374, as cited in Gustafson et al. 2010). The SRS was 

constructed in 1989 about 49 km above the confluence of the Toutle and Cowlitz rivers, 

is approximately 50 m in height, and extends 600 m across the valley of the North Fork 

Toutle River. The SRS continues to be a source of fine sediment to the lower Cowlitz 

River (LCFRB 2004a, as cited in Gustafson et al. 2010). Anderson (2009, p. 5 as cited in 

Gustafson et al. 2010,) stated that: 

The SRS [on the Toutle River], constructed by the USACE, has become 

ineffective at trapping sediments. Lower Cowlitz River eulachon spawning habitat 

is considered degraded while the Toutle River is assumed absent of spawning 

habitat due to this fine sediment inundation. ... WDFW considers past and 

continued fine sediment deposition in the Toutle and Cowlitz rivers as a moderate 

to high risk for eulachon. 

There are three major dams on the mainstem Lewis River, also known as the North Fork Lewis 

River: Merwin Dam (aka Ariel Dam) at RKM 31.4, built in 1931, forms Lake Merwin; Yale 

Dam at RKM 55, built in 1953, forms Yale Lake; and Swift Dam at RKM 77.1, built in 1958, 

forms Swift Creek Reservoir (Wade 2000a, as cited in Gustafson et al. 2010). The Lower 

Columbia Fish Recovery Board (LCFRB 2004a, p. G-35, as cited in Gustafson et al. 2010) stated 

that: 

Hydropower regulation has altered the hydrograph of the lower mainstem [of the Lewis 

River].... Pre-dam data reveals peaks due to fall/winter rains, winter rain-on-snow, and 

spring snowmelt. Post-dam data shows less overall flow variation, with a general increase 

in winter flows due to power needs. Post-dam data shows a decrease in spring snowmelt 

flows due to reservoir filling in preparation for dry summer conditions.... The risk of 

extreme winter peaks has also been reduced, with the trade-off being the reduction of 

potentially beneficial large magnitude channel-forming flows. ... The long-term effects 

on channel morphology and sediment supply have not been thoroughly investigated.

Canada—In British Columbia there are an estimated 802 licensed dams in the Fraser 

River Basin, mostly for irrigation purposes in the dryer areas above Hope (Birtwell et al. 1988, 

as cited in Gustafson et al. 2010). The impact on eulachon of water withdrawals associated with

reservoirs in the Fraser River has not been studied. The other eulachon river in British Columbia 
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where hydrology has been significantly altered by water diversions is the Kemano River where a 

hydroelectric plant began operating in 1954 (Lewis et al. 2002, as cited in Gustafson et al. 2010).

Conclusion 

Based on this information, the threat occurs at a very low to moderate severity and there is a high 

level of uncertainty. Thus, the relative impact to recovery is ranked moderate-to-high. 

Threat—Dredging

Subpopulation Klamath Columbia Fraser BC

BRT Ranking No Ranking 6 7 12

BRT Threat Severity Not Scored Moderate Very Low Very Low

Listing Factor A A A A

Dredging impacts physical habitat features by altering the geomorphic structure of the river 

bottom with resultant changes in hydraulic geometry (Leopold and Maddock 1953) and sediment 

transport, negatively affecting habitat forming processes and ecological and biological 

interactions. 

The following is a summary of expected dredging-related effects on eulachon based on 

Gustafson et al. (2010).

Potential dredging impacts on eulachon consist of direct effects of entrainment of adults and eggs 

and potential for smothering of eggs with sediment (Howell and Uusitalo 2000, Howell et al. 

2001; as cited in Gustafson et al. 2010). Indirect effects may consist of altering the freshwater 

spawning habitat and estuarine nursery habitat. Larson and Moehl (1990) documented direct 

entrainment of small amounts of eulachon by hopper dredge at the mouth of the Columbia River 

during May-October 1985–1988. Johnston (1981, p. 427; as cited in Gustafson et al. 2010) 

reviewed dredging activities in estuarine environments and listed “increased turbidity; altered 

tidal exchange, mixing, and circulation; reduced nutrient outflow from marshes and swamps; 

increased saltwater intrusion; and creation of an environment highly susceptible to recurrent low 

dissolved oxygen levels” as negative impacts. 

Hay and McCarter (2000) indicated that dredging during the eulachon spawning season in the 

Fraser River continued until the late 1990s. Tutty and Morrison (1976, as cited in Gustafson et 

al. 2010) estimated about 0.9 mt of adult eulachon were directly entrained during hopper 

dredging activities between March 15 and June 4, 1976, on the lower Fraser River. Hay and 

McCarter (2000, p. 38) stated that “the direct loss of about 1 tonne of eulachons may have been 

small relative to potential deleterious impacts on survival of eulachons eggs—either from the 

direct effect of entrainment of spawned eggs, or the silt-induced smothering of eggs deposition 

[sic] in waters downstream of the dredging operations.” Hay and McCarter (2000) suggested 

dredging [in the Fraser River] should be confined to periods outside of the spawning season to 
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minimize impacts on eulachon and that the effects of sediment removal on eulachon spawning 

habitats should be a topic of research.

FREMP (2007, as cited in Gustafson et al. 2010) estimated that from 0.76 to 3.22 million cubic 

meters of sediment were dredged annually from the lower Fraser River during the years 1997–

2007 to prevent grounding of commercial shipping. Increases in vessel size have required 

deepening of the shipping channel in recent years (FREMP 2007, as cited in Gustafson et al. 

2010). As mentioned in Pickard and Marmorek (2007, as cited in Gustafson et al. 2010), suction 

dredging is currently restricted to months when eulachon are not spawning in the Fraser and 

Kitimat rivers. According to FREMP (2006, p. 40; as cited in Gustafson et al. 2010), “hydraulic 

suction dredging and large-scale clamshell dredging undertaken in the Fraser River estuary is 

restricted so that there is no dredging conducted from March 1 to June 15 of any given year.” 

It has been suggested that eulachon spawning distribution in the Fraser River has changed in 

response to dredging and channelization and that dredging, even outside of the spawning period, 

affects eulachon by destabilization of substrates (Pickard and Marmorek 2007, as cited in 

Gustafson et al. 2010). Pickard and Marmorek (2007, p. 8; as cited in Gustafson et al. 2010) 

reported in their summary of findings of a DFO workshop to determine research priorities for 

eulachon that “there is consensus that dredging is not the cause of the coastwide decline in 

eulachon, but there is disagreement about the importance of dredging impacts on eulachon 

resilience in rivers where it occurs.” 

USACE (2007, as cited in Gustafson et al. 2010) stated that: 

...as much as 414 million cubic yards (mcy) of material will erode from the Mount St. 

Helens sediment avalanche through year 2035. In addition, it was estimated that over the 

period from 2000 to 2035 as much as 27 mcy of this material would be deposited in the 

lower Cowlitz River and will need to be removed in order to maintain flood protection 

levels in Kelso, Longview, Castle Rock, and Lexington. ... This trend is a result of 

increased sedimentation from the Toutle River watershed from sediments being passed 

through the sediment retention structure (SRS) in greater amounts. The ability of the SRS 

to trap sand has decreased since 1998 when the sediment reservoir behind the dam filled 

in. All flow now passes through the spillway as designed, carrying sediment downstream. 

... Significant sand deposition ... continues to occur at the mouth of the Cowlitz River, 

which has severely reduced the capacity of the river channel to transport sand. ... 

Channel capacity and the authorized levels of flood protection for Kelso, Longview, 

Lexington, and Castle Rock have been reduced below authorized levels due to sediment 

deposition in the lower Cowlitz River. ... In addition to the initial dredging effort, annual 

follow-on dredging from the transition area to Cowlitz RM 2.5 [RKM 4.0] to maintain 

the dredged channel depths and bottom widths will be needed to maintain flood 

protection levels for the next 5 years. The Corps is also investigating long-term dredging 
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and non-dredging alternatives that would maintain the authorized levels of flood 

protection for the communities on the lower Cowlitz River through the year 2035. 

Furthermore, USACE’s environmental assessment of interim dredging activities on the Cowlitz 

River (USACE 2007, p. 33; as cited in Gustafson et al. 2010) indicated that: 

The proposed ... dredging action may affect spawning adults, outmigrating juveniles, and 

larvae [of eulachon] in the water column by entrainment. Eggs may be affected by 

removing substrate needed to allow egg adhesion for incubation and by covering of 

incubating eggs by increasing suspended sediment. 

Sherwood et al. (1990, as cited in Gustafson et al. 2010) provided a detailed analysis of historical 

dredging activities in the Columbia River estuary through the 1980s. They estimated that about 

300 million cubic meters of largely sand-sized material were removed from the estuary and river 

channels between 1909, when substantial dredging started, and 1982. Currently, USACE 

routinely dredges the mainstem Columbia River shipping channel. The Washington and Oregon 

Eulachon Management Plan (WDFW/ODFW 2001, p. 25; as cited in Gustafson et al. 2010) 

stated that this “Dredging should not be conducted in winter and early spring to avoid 

entrainment of eulachon adults or larvae.” Romano et al. (2002) suggested that the dynamic 

nature of sand sediments in areas proposed for channel deepening in the Columbia River were 

unlikely to support eulachon egg incubation and that direct effects of dredging in these areas on 

eulachon would be minimal. However, “[eulachon] eggs incubating in near-shore areas in the 

proximity of dredging activities might be affected if these activities alter flow patterns or 

increase sedimentation” (Romano et al. 2002, p. 8).

In response to an earlier draft of the present status review document, Anderson (2009, p. 4–5; as 

cited in Gustafson et al. 2010) stated that: 

Risks dependent on timing, location, and life history stage in relation to dredging and inwater dredge material disposal pose a low to moderate threat for adult eulachon and a 

high risk for incubating eggs. ... WDFW considers dredging effects on adult eulachon as 

a low risk in the mainstem Columbia River and a low to moderate risk in the tributaries. 

... The risk to larval eulachon from mainstem Columbia River dredging activities is low 

and in the tributaries is moderate. ... Dredging activities can affect egg survival through 

direct entrainment and from suffocation through burial. The risk to eulachon eggs from 

dredging and in-water dredge material disposal in eulachon spawning habitat is high.

Conclusion

Based on this information, the threat occurs at a very low to moderate severity and there is a 

medium level of uncertainty. Thus, the relative impact to recovery is ranked moderate.
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B. Over-utilization for Commercial, Recreational, Scientific, or Educational Purposes 

Threat—Commercial Harvest

Subpopulation Klamath Columbia Fraser BC

BRT Ranking No Ranking 9 6 No Ranking

BRT Threat Severity Not Scored Low Low Not Scored

Listing Factor B B B B

Threat—Tribal/First Nations Fisheries

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 11 14 13 10

BRT Threat Severity Very Low Very Low Very Low Low

Listing Factor B B B B

Threat—Recreational Harvest

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 13 13 14 14 

BRT Threat Severity Very Low Low Very Low Very Low 

Listing Factor B B B B 

Historically, eulachon were caught in commercial, recreational, and tribal/First Nations fisheries 

along the West Coast of the United States and Canada. 

Columbia River Subpopulation: 

The historical landings data for the Columbia River subpopulation goes back as far as 

188825 (Figure 2-2) with newspaper reports as far back as 186626. For the Columbia River 

subpopulation, we considered the historical landings data (commercial and sport dip net 

fishery) as a minimum measure of fish abundance. Based on the commercial landings 

data, we assumed that in order to maintain a commercial fishery of 22,000,00027 (the 

geometric mean of the commercial landings data for the years 1936 through 199228; 

range 6,000,000 to 64,000,000 fish) fish per year over the 56-year period (1936 through 

1992), that the total run size must have been substantially higher than the geometric mean 

of 22,000,000 fish29 landed. In addition to the commercial fishery, is the sport dip net 

 

25 Ceremonial and subsistence fishery for Washington and Oregon Indian Tribes in the Columbia River Basin has 

taken place for thousands of years. However, there are no reliable records for landings. 

26 The Oregonian, 24 February, 1866. 

27 All landings estimates were rounded. 

28 Commercial harvest data is available from 1888 – 2010 for the whole Columbia River system (most years, a few 

missing) and broken down by state (early years) and/or tributaries (mostly after 1935). Harvest is reported as pounds 

landed (converted to numbers of fish). We restrict the data to the period 1936 – present so that we have a consistent 

set of tributary data, and because earlier data may be more unreliable. 

29 For example, based on results from the spawning stock biomass estimations in 2013-2014, the estimated run size of 

eulachon in the Columbia River ranged from 83,000,000 to 330,000,000 fish, with a mean estimate of 186,000,000 

fish. 
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fishery, first reported in 186530. However, there are no reliable landings data available for 

the sport dip net fishery other than an exploratory sampling program conducted by the 

WDFW in 1978 on the Cowlitz River31. Based on the information collected from this 

exploratory sampling program, WDFW estimated that the sport dip net fishery was 

comparable to the commercial harvest. As this exploratory sampling program is the only 

reliable landings data for the sport dip net fishery available, we used it as a proxy for the 

sport dip net fishery for the years 1936 through 1992 as part of our run size estimations. 

This approach results in a recreational harvest potential of 22,000,000 fish per year, and a 

combined commercial and sport fishery of 12,000,000 to 128,000,000, adult eulachon per 

year. 

 

30 Huntington 1963.

31 WDFW memorandum—Cowlitz River smelt sport dip net fishery total catch estimate.
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Table 2-3. Annual Columbia River eulachon run size 2000-2017; pounds converted to numbers of fish at 

11.16 fish/pound (WDFW 2016). The estimates were calculated based on methods developed by (Parker 

1985), Jackson and Cheng (2001), and Hay et al. (2002) to estimate spawning biomass of pelagic fishes. For 

2000 through 2010 estimates were back-calculated using historical larval density data.

Maximum 

Estimates

Mean 

Estimates

Minimum 

Estimates

Year

8,971,500 5,421,500 3,205,200 2000

128,960,500 77,512,900 35,121,600 2001

76,645,800 59,114,500 42,541,900 2002

99,395,400 64,670,000 45,137,700 2003

— — — 2004

1,450,800 783,400 226,500 2005

3,527,700 1,233,200 387,300 2006

3,272,100 1,605,900 863,800 2007

6,510,700 2,418,400 713,100 2008

10,034,000 4,873,600 1,984,200 2009

4,281,000 1,759,900 612,700 2010

69,661,800 36,775,900 17,860,400 2011

61,437,400 35,722,100 20,008,600 2012

197,943,400 107,794,900 45,546,700 2013

323,778,300 185,965,200 84,243,100 2014

207,570,500 123,582,000 57,525,700 2015

111,991,000 54,556,500 21,654,800 2016

34,071,100 18,307,100 8,148,600 2017
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Figure 2-2. Number of eulachon caught in the Columbia River and Tributary commercial fishery, 1888-2017.

0

10,000,000

20,000,000

30,000,000

40,000,000

50,000,000

60,000,000

70,000,000

18881891189418971900190319061909191219151918192119241927193019331936193919421945194819511954195719601963196619691972197519781981198419871990199319961999200220052008201120142017

Number of fish

Year

Number of eulachon caught in Columbia River and 

Tributary Commercial Fishery (11.2 fish/pound)
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Figure 2-3. Annual Columbia River eulachon run size, harvest, and exploitation rate estimates, 2000- 2017

(WDFW).
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Fraser River Subpopulation:

The historical landings data for the Fraser River subpopulation goes back as far as 1881 (Figure 

2-4). For the Fraser River subpopulation, we considered the historical landings data as a 

minimum measure of fish. Based on the landings data, we assumed that in order to maintain a 

commercial fishery of 1,100,00032 (geometric mean; range 90,000 to 8,000,000 fish) fish per 

year over a 56 year period (1936 through 1992)33, that the total escapement must have had to 

have been substantially higher than the geometric mean of 1,100,000 fish landed. 

Figure 2-4. Landings data for the commercial fishery on the Fraser River for the years 1881 through 2004.

 

32 All landings estimates were rounded.

33 Commercial harvest data is available from 1881 – 2004 for the Fraser River. Harvest is reported as metric tons 

landed (converted to numbers of fish). We restrict the data to the period 1936 – present so that we have a consistent 

set of data with the Columbia River, and because earlier data may be more unreliable.

0.00

50.00

100.00

150.00

200.00

250.00

300.00

350.00

400.00

18811885188918931897190119051909191319171921192519291933193719411945194919531957196119651969197319771981198519891993199720012005

Catch (metric tons)

Year

Fraser River Commercial Fishery Catch
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Table 2-4. Annual Fraser River eulachon run size 1995-2017. The estimates were calculated based on 

methods developed by Parker (1985), Jackson and Cheng (2001), and Hay et al. (2002) to estimate spawning 

biomass of pelagic fishes.

Combined 

Biomass/Pounds

Number of Fish at 9.9 

Fish/Pound

Number of Fish at 13.3 

Fish/Pound

Year

665,796 6,591,380 8,855,087 1995

4,213,034 41,709,037 56,033,352 1996

163,142 1,615,106 2,169,789 1997

299,829 2,968,307 3,987,726 1998

921,532 9,123,167 12,256,376 1999

286,601 2,837,350 3,811,793 2000

1,342,615 13,291,889 17,856,780 2001

1,089,084 10,781,932 14,484,817 2002

586,430 5,805,657 7,799,519 2003

72,753 720,255 967,615 2004

35,274 349,213 469,144 2005

63,934 632,947 850,322 2006

90,390 894,861 1,202,187 2007

22,046 218,255 293,212 2008

30,865 305,564 410,505 2009

11,023 109,128 146,606 2010

68,343 676,596 908,962 2011

264,555 2,619,095 3,518,582 2012

220,462 2,182,574 2,932,145 2013

145,505 1,440,500 1,935,217 2014

698,865 6,918,764 9,294,905 2015

97,003 960,330 1,290,140 2016

77,162 763,901 1,026,251 2017
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BC Subpopulation:

The historical landings data for the BC subpopulation goes back as far as 1877 (Figure 2-5). For 

the BC subpopulation, we considered the historical landings data as a minimum measure of fish. 

Based on the landings data, we assumed that in order to maintain a First Nations fisheries of 

800,00034 (geometric mean; range 9,000 to 5,000,000 fish35) fish over a 56 year period (1936 

through 1992)36, that the total escapement must have been substantially higher than the mean of 

800,000 fish landed.

Figure 2-5. Landings data for the BC coastal subpopulation 1877-2009.

Klamath River Subpopulation:

The historical landings data for the Klamath River subpopulation is extremely limited. The only 

reliable landings data is for 1963, when a total of 650,00037 fish were reported to have been 

landed. Based on the limited nature of the data we cannot estimate the fraction of the harvest 

relative to the total run (escapement). Nonetheless, what is known is that eulachon harvests have 

 

34 All landings estimates were rounded.

35 In 2001 DFO conducted a spawning stock biomass estimation for the Skeena River with a mean estimate of 

10,733,968 fish, Lewis et al. (2009).

36 Harvest data is available from 1887 – 2009 for the BC subpopulation (multiple rivers). Harvest is reported as metric 

tons landed (converted to numbers of fish). We restrict the data to the period 1936 – present so that we have a consistent 

set of data with the Columbia and Fraser River, and because earlier data may be more unreliable.

37 All landings estimates were rounded.

0

50

100

150

200

250

18771883188918951901190719131919192519311937194319491955196119671973197919851991199720032009

Landings (mt)

Year

Knight Inlet

(Klinaklini River)

Rivers Inlet

Bella Coola River

Kemano River

Skeena River
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been documented for this subpopulation for more than 100 years, albeit intermittently, as far 

back as 1879, and in the years 1919, 1963, 1968, 1969, 1976, 1978, 1979, and 1980 (Gustafson 

et al. 2010). Recent reports from Yurok tribal fisheries biologists report capturing adult eulachon 

in presence/absence surveys (seine/dip nets) in the Klamath River over a four-year period [2011 

(7 eulachon), 2012 (40 eulachon), 2013 (112 eulachon), and 2014 (1,000 eulachon)]38. 

Conclusion 

Based on this information, the threat occurs at a very low to low severity and there is a medium 

level of uncertainty. Thus, the relative impact to recovery is ranked low-to-moderate. 

Threat—Scientific Monitoring

Subpopulation Klamath Columbia Fraser BC

BRT Ranking No Ranking 16 16 15

BRT Threat Severity Not Scored Very Low Very Low Very Low

Listing Factor B B B B

Scientific monitoring on eulachon is very limited. 

Conclusion 

Based on this information, the threat occurs at a very low severity and there is a low level of 

uncertainty. Thus, the relative impact to recovery is ranked very low. 

C. Disease or Predation 

Threat—Disease

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 8 11 11 7

BRT Threat Severity Very Low Very Low Very Low Very Low

Listing Factor C C C C

The following is a summary of disease-related effects on eulachon based on Gustafson et al. 

(2010).

Eulachon can be infected by a variety of bacterial, viral, fungal, and microparasitic pathogens. 

Numerous diseases can result from pathogens that occur naturally in the wild. The BRT (as cited 

in Gustafson et al. 2010) found very little information relative to impacts of diseases on 

eulachon. Hedrick et al. (2003, as cited in Gustafson et al. 2010) isolated viral hemorrhagic 

septicemia virus (VHSV) for the first time from adult eulachon collected in March 2001 in 

Oregon’s Sandy River. Six of 15 pooled samples, each consisting of 5 fish, tested positive for 

VHSV. The overall impact of this virus on eulachon is difficult to assess. This virus has been 

 

38 E-mail from Barry McCovey, Yurok Indian Tribe on March 17, 2014, to Robert Anderson, NMFS. 
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isolated from a wide range of marine fish hosts and given the right conditions may “cause 

significant disease associated with morbidity and mortality in populations of marine fish” 

(Hedrick et al. 2003, p. 212; as cited in Gustafson et al. 2010).

Conclusion 

Based on this information, the threat occurs at a very low severity and there is a medium level of 

uncertainty. Thus, the relative impact to recovery is ranked low. 

Threat—Predation

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 5 7 3 3

BRT Threat Severity Moderate Moderate Moderate Moderate

Listing Factor C C C C

The following is a summary of expected predation-related effects on eulachon based on 

Gustafson et al. (2010).

Significant numbers of eulachon are lost to fish, avian, and pinniped predators in freshwater and 

marine environments. Beach et al. (1981, 1985; as cited in Gustafson et al. 2010) and Jeffries 

(1984, as cited in Gustafson et al. 2010) observed that harbor seals, California sea lions, and 

Steller sea lions (Eumetopias jubatus) move into the Columbia River to feed on eulachon runs in 

the winter. Jeffries (1984, p. 20; as cited in Gustafson et al. 2010) observed that “harbor seals 

were frequently reported in the area where the Cowlitz River enters the Columbia” and “these 

population increases ... were apparently due to the migration of eulachon into spawning 

tributaries.” Many harbor seals migrate from Grays Harbor and Willapa Bay to the Columbia 

River in the winter (Beach et al. 1985, as cited in Gustafson et al. 2010). Between 1,000 and 

1,500 harbor seals have been observed using haul out sites as far as 45 miles upriver on the 

Columbia River at this time of year and “are frequently seen as far upriver as Longview, 

Washington (RM 55 [RKM 88.5]), apparently following eulachon runs into this area” (Beach et 

al. 1981, p. 73; as cited in Gustafson et al. 2010). NMFS (1997, p. 29; as cited in Gustafson et al. 

2010) stated that the highest counts of seals in the river coincide with the winter spawning of 

eulachon. 

Based on the presence of otoliths in harbor seal scat collected from the Columbia River during 

1981–1982, Jeffries (1984, as cited in Gustafson et al. 2010) reported that eulachon were eaten 

by 50%, 87%, 44%, and 12% of the harbor seals present in January, February, March, and April, 

respectively. Brown et al. (1989, as cited in Gustafson et al. 2010) determined that 98% of the 

prey eaten by harbor seals in the Columbia River during the winters of 1986 to 1988 was 

eulachon, and that 100% of harbor seal stomachs examined contained eulachon (Brown et al. 

1989, NMFS 1997; as cited in Gustafson et al. 2010). Brown et al. (1989, as cited in Gustafson et 

al. 2010) also estimated that the more than 2,000 harbor seals present during mid-winter 1987 in 

the Columbia River consumed from 2.5 to 10.2 million eulachon or from 105 to 428 mt 
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(assuming an average weight of 42 g per eulachon), which is equal to 12% to 50% of the 

Columbia River commercial fishery landings of eulachon for that year. 

Although accounting for only 0.4% of the diet, Olesiuk (1993, as cited in Gustafson et al. 2010) 

estimated that the 12,000–15,000 harbor seals present in the Strait of Georgia during 1988 

consumed an average of approximately 40 mt of eulachon. Eulachon are also a primary prey 

species of California sea lions in the Columbia River in January to June (Beach et al. 1985, 

Brown et al. 1995, NMFS 1997; as cited in Gustafson et al. 2010), and California sea lions have 

been observed near Longview at the time of the eulachon run (Beach et al. 1981, as cited in 

Gustafson et al. 2010). Jeffries (1984, p. 17, as cited in Gustafson et al. 2010) observed that peak 

numbers of California sea lions (200–250) in the Columbia River occurred during the months of 

February and March and they were believed to “move upriver following and feeding on the 

annual eulachon smelt runs.” Maximum numbers of Steller sea lions (80–100) in the Columbia 

River also occurred during this time of year when they “have been observed feeding upriver on 

eulachon” (Jeffries 1984, p. 19; as cited in Gustafson et al. 2010). Seals and sea lions have also 

been observed above New Westminster in the Fraser River during the eulachon spawning 

migration (Hay and McCarter 2000). 

Northern fur seals consume eulachon in the California Current (Antonelis and Fiscus 1980, as 

cited in Gustafson et al. 2010) and particularly offshore of Oregon and Washington (Antonelis 

and Perez 1984, as cited in Gustafson et al. 2010). Peak numbers of northern fur seals appear off 

Oregon and Washington in April (Antonelis and Perez 1984, as cited in Gustafson et al. 2010). 

Based on fur seal diet analyses, Antonelis and Perez (1984, as cited in Gustafson et al. 2010) 

calculated that fur seals consumed a yearly average of 600 mt of eulachon in this offshore region 

between 1958 and 1974. Spalding (1964, as cited in Gustafson et al. 2010) reported that about 

100 yearling fur seals congregated at the head of Knight Inlet in March 1961 and that four of 

these fur seals had been feeding exclusively on eulachon in the Klinaklini River estuary, while 

another 60 fur seals in the middle of the inlet were feeding on squid. Clemens et al. (1936, p. 6; 

as cited in Gustafson et al. 2010) reported on an analysis of stomach contents of 593 northern fur 

seals sampled from late March to late June off the west coast of Vancouver Island and stated 

that: 

Eulachon proved to be the third most important organism in the food of the fur seals 

[after herring and salmon]. It was found to occur in some 20% of the full stomachs but as 

a rule in rather small quantities. It comprised about 3% of the total food. 

Eulachon occurred in 100% of 229 spiny dogfish stomachs containing food taken in the Fraser 

River in May 1953, and in 23% and 92% of stomachs analyzed outside the river’s mouth in May 

1950 and 1953, respectively (Chatwin and Forrester 1953, as cited in Gustafson et al. 2010). 

According to Chatwin and Forrester (1953, p. 38), “The dogfish which support the fishery in the 

Fraser River in mid-May are clearly dependent upon the appearance of the eulachon.” Analyses 

of more than 14,000 spiny dogfish stomachs in British Columbia waters over a 30-year period 
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ending in 1977 revealed that eulachon represented approximately 5.5% of the annual dogfish 

diet, and represented a greater percentage of food types consumed for young (13.4%) and 

immature (10.2%) dogfish than for adults (1.6%) (Jones and Geen 1977, as cited in Gustafson et 

al. 2010). 

Eulachon occurred at low frequency (<1%) in 416 Pacific cod stomachs examined in British 

Columbia (Hart 1949, as cited in Gustafson et al. 2010). Eulachon are also eaten by large Pacific 

hake, which become increasingly piscivirous as they age, with euphausiids being the dominant 

prey of small Pacific hake (Rexstad and Pikitch 1986, Buckley and Livingston 1997; as cited in 

Gustafson et al. 2010). Livingston (1983, p. 630; as cited in Gustafson et al. 2010) determined 

that eulachon off Oregon in the spring of 1980 “comprised 22% by weight of the diet of 450–549 

mm Pacific whiting [hake] and 79.6% by weight of the diet of 550+ mm fish.” The offshore 

Pacific hake stock migrates northward from winter spawning grounds to feed off the coast of the 

Pacific Northwest in the summer. This stock represents 61% of the offshore pelagic biomass in 

the California Current system (Ware and McFarlane 1995), and recent evidence (Benson et al. 

2002, Cooke et al. 2006, Phillips et al. 2007; as cited in Gustafson et al. 2010) indicates that the 

feeding migration of Pacific hake may be extending further north within the northern California 

Current system. Although only about 5% of Pacific hake stomachs examined by Outram and 

Haegele (1972, as cited in Gustafson et al. 2010) off the west coast of Vancouver Island in 1970 

contained eulachon, the large biomass of Pacific hake in this region in summer may have a 

significant impact on eulachon biomass in the area (Hay and McCarter 2000).

Conclusion 

Based on this information, the threat occurs at a moderate severity and there is a high level of 

uncertainty. Thus, the relative impact to recovery is ranked moderate. 

D. Inadequacy of Existing Regulatory Mechanisms 

Inadequacy of Regulatory Mechanisms

Subpopulation Klamath Columbia Fraser BC

BRT Ranking No Ranking No Ranking No Ranking No Ranking

BRT Threat Severity Not Scored Not Scored Not Scored Not Scored

Listing Factor D D D D

At the time of listing, the primary factors responsible for the decline of eulachon are the 

destruction, modification, or curtailment of habitat and inadequacy of existing regulatory 

mechanisms (75 FR 13012), specifically the lack of regulations concerning bycatch of eulachon 

in commercial fisheries. 
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E. Other Natural or Manmade Factors Affecting its Continued Existence 

Threat—Eulachon Bycatch

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 3 2 2 2

BRT Threat Severity Moderate High Moderate High

Listing Factor E E E E

The following is a summary of bycatch-related effects on eulachon based on Gustafson et al. 

(2010), Gustafson et al. (2015, 2016, 2017), Hannah and Jones (2012), and Hannah et al. (2015).

Bycatch-Shrimp Fishery—Ocean shrimp fisheries began in California in 1952 and 

expanded into Oregon and Washington by the mid- to late-1950s (Frimodig et al. 2009, as cited 

in Gustafson et al. 2017). Ocean shrimp in commercial quantities are found from Point Arguello, 

California north to Queen Charlotte Sound, British Columbia, typically over well-defined beds of 

green mud or green mud and sand (Frimodig et al. 2009, as cited in Gustafson et al. 2017). 

Because ocean shrimp undergo a vertical diel migration, dispersing into surface waters during 

nighttime hours and returning to near bottom aggregations in the daytime (Zirges and Robinson 

1980, Frimodig et al. 2009, as cited in Gustafson et al. 2017), ocean shrimp vessels generally 

trawl in depths ranging from 91–256 m (50 to 140 fathoms) during daylight hours. 

The ocean shrimp season is open April 1 through October 31 in all three states and vessels 

deliver catch to shore-based processors. Total coast-wide ocean shrimp landings have ranged 

from a low of 1,888 mt in 1957 to a high of 46,494 mt in 2015 (Fig. 2-6). The portion of the 

catch that is not marketable or for which regulations prohibit landing is discarded at-sea. 

Incidental Bycatch 

Prior to 2000, bycatch in the ocean shrimp fishery ranged from 32 to 61% of the total catch 

(Hannah and Jones 2007, as cited in Gustafson et al. 2010). Indirect mortality includes mortality 

of fish harvested incidentally to the target species, fish that die after being captured by fishing 

gear but not landed, and fish that die after being caught and released. Despite the various 

methods used to target a specific species, incidental bycatch—the harvest of non-targeted 

species— still occurs, largely because various species intermingle in the marine environment. 

Eulachon occur as bycatch in shrimp trawl fisheries off the coasts of Washington, Oregon, 

California, and British Columbia (Hay et al. 1999a, 1999b, Olsen et al. 2000, NWFSC 2008, 

Hannah and Jones 2009; as cited in Gustafson et al. 2010). Offshore trawl fisheries for ocean 

shrimp (Pandalus jordani) occur from the west coast of Vancouver Island to the U.S. West Coast 

off Cape Mendocino, California (Hannah and Jones 2003, as cited in Gustafson et al. 2010). 

Pandalus jordani is known as the ocean pink shrimp or smooth pink shrimp in Washington, pink 

shrimp in Oregon, and Pacific Ocean shrimp in California. Herein we use the common name 

ocean shrimp in reference to P. jordani as suggested by the American Fisheries Society 
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(McLaughlin et al. 2005, as cited in Gustafson et al. 2010). Similar trawl fisheries operate in 

British Columbia, which mainly target ocean shrimp (aka smooth pink shrimp in Canada), 

northern pink shrimp (P. borealis eous), and sidestripe shrimp (Pandalopsis dispar) (Hay et al. 

1999a, 1999b, Olsen et al. 2000, Hannah and Jones 2007, NWFSC 2008, DFO 2009c; as cited in 

Gustafson et al. 2010).

Figure 2-6. Commercial landings in ocean shrimp trawl fisheries off the U.S. west coast through 2016 

(Gustafson et al. 2017).

Following recognition that large numbers of eulachon were occurring as bycatch in Queen 

Charlotte Sound shrimp fisheries (Hay and McCarter 2000, Olsen et al. 2000; as cited in 

Gustafson et al. 2010) and of a concurrent decline in central coast British Columbia eulachon 

stocks, DFO closed the Queen Charlotte Sound shrimp trawl fishery in 1999, which has 

remained closed “because of concerns for central coast eulachon stocks” (DFO 2009c, p. 11; as 

cited in Gustafson et al. 2010). Concerns over eulachon bycatch in the offshore west coast 

Vancouver Island shrimp trawl fisheries also led DFO to set eulachon bycatch action levels for 

west coast Vancouver Island (DFO 2009c, 2009d; as cited in Gustafson et al. 2010). This action 

level is set at 1% of the west coast Vancouver Island eulachon abundance index, which is based 

on biomass estimates of eulachon derived from the annual shrimp abundance survey (DFO 

2009c, p. 11; as cited in Gustafson et al. 2010). If estimated eulachon bycatch exceeds this 1% 

level, additional “management actions could include: closure of the shrimp trawl fishery, closure 

of certain areas to shrimp trawling, or restricting trawling to beam trawlers which have been 
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found to have a lower impact on eulachon than otter trawlers” (DFO 2009d, p. 15; as cited in 

Gustafson et al. 2010). Similar action levels are not in place off the U.S. West Coast.

Bycatch Reduction Efforts

Beginning in 2000 in British Columbia and 2003 in Washington, Oregon, and California, 

mandated use of BRDs in offshore shrimp trawl fisheries has substantially reduced bycatch of fin 

fish in these fisheries (Hannah and Jones 2007, Frimodig 2008; as cited in Gustafson et al. 2010). 

Currently, ocean shrimp vessels are required to use bycatch reduction devices (BRDs) that serve 

as deflecting grids to guide fin-fish towards an escape opening, which is usually on the top of the 

net. The primary goal of mandatory BRDs is to reduce bycatch of groundfish species, and more 

recently, protected species such as eulachon. BRDs became mandatory in California in 2002 

(Frimodig 2008, Frimodig et al. 2009, as cited in Gustafson et al. 2017) and in Washington and 

Oregon in 2003. Current 2017 regulations in Washington and Oregon, adopted by both states in 

2012, require ocean shrimp trawl fishery BRDs to consist of a rigid panel or grate of narrowly 

spaced bars (usually constructed of aluminum) with no gaps between the bars exceeding 0.75 

inches (19.1 mm). Approved BRDs for use in the ocean shrimp fishery in California include: (1) 

rigid- or semi-rigid grate excluders consisting of vertical bars with no gaps between the bars 

exceeding 2 inches (50.8 mm); (2) soft-panel excluders, usually made of a soft mesh material 

“with individual meshes no large than 6 inches;” and (3) fisheye excluders, which have a forward 

facing escape opening that is maintained by a rigid frame.

Bycatch Estimations—2004-2015

Total estimated bycatch of eulachon in the Washington ocean shrimp fisheries ranged from a low 

of over 64 thousand (95% CI; 23,950–132,532) fish in 2010 to a high of over 22.4 million (95% 

CI; 16,809,929–28,991,135) fish in 2015 (Table A2, as cited in Gustafson et al. 2017). Mean 

estimated total biomass of eulachon bycatch in the Washington fishery during this time period 

(2010–2015) ranged from 2.1–219.8 mt (Table A2, as cited Gustafson et al. 2017). The 

Washington sector bycatch ratio, on a kg of eulachon per metric ton of retained shrimp basis, 

was highest during 2012 (37.9 kg/mt) and 2013 (32.9 kg/mt) and lowest in 2010 (0.5 kg/mt) and 

2011 (1.3 kg/mt). Recently, this bycatch ratio has somewhat declined from high levels in 2012–

2013 to 10.2 kg/mt in 2014 and 11.7 kg/mt in 2015 (Table A2, as cited in Gustafson et al. 2017). 

The Washington ocean shrimp fishery was also observed separately in 2011 and 2012 by a team 

of state-deployed fishery bycatch observers (Wargo et al. 2014, as cited in Gustafson et al. 

2017). Wargo et al. 2014 (as cited in Gustafson et al. 2017) reported a fleetwide eulachon 

bycatch in the Washington state ocean shrimp fishery of “7.8 mt (17,132 pounds) for 2011 and 

171 mt (378,011 pounds) for 2012.” These bycatch estimates are approximately 30% and 10% 

greater than the estimates for the Washington ocean shrimp fishery as reported in the present 

document of 5.5 and 156.8 mt in 2011 and 2012, respectively. In the 2011 Washington ocean 

shrimp trawl fishery 24% of trips were observed by the state observers (Wargo et al. 2014, as 
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cited in Gustafson et al. 2017), whereas the West Coast Groundfish Observer Program 

(WCGOP) observed 16.6% of the total ocean shrimp landings (Table xx). In 2012, 16% of trips 

were observed by the state observer program (Wargo et al. 2014, as cited in Gustafson et al.

2017) and 14.8% of shrimp landings were observed by the WCGOP (Table xx). 

Table 2-5. Numbers and weight of eulachon observed and bycatch ratios from ocean shrimp trawl vessels that 

landed their catch in Washington (2010–2015). Bycatch ratios were calculated for each year by dividing the 

observed catch of eulachon (in numbers of eulachon and in kg of eulachon) by the observed weight (in mt) of 

retained ocean shrimp. A fleet-wide bycatch estimate (in both weight and number of fish) was obtained by 

multiplying the bycatch ratios by fleet-wide ocean shrimp landings. 95% bootstrapped confidence intervals 

(CI) are provided for the estimates. Asterisks (*) signify strata with fewer than three observed vessels.

Eulachon bycatch in the Oregon ocean shrimp fishery was estimated at well under a million 

individual fish (range of 146–845 thousand) from 2004–2011 (although the fishery was over 28.1 

million (95% CI; 18.0–39.3 million) and 34.7 million (95% CI; 19.9–52.5 million), respectively 

(Table A3, as cited in Gustafson et al. 2017). Similarly, total weight of estimated eulachon 

bycatch in Oregon increased from 20.4 mt (95% CI; ~16.3–22.8 mt) in 2011 to nearly 428 mt 

(95% CI; ~387–497 mt) in 2012 and to over 540 mt (95% CI; ~430–736 mt) in 2013.

Subsequently, estimated eulachon bycatch has remained high in the Oregon ocean shrimp trawl 

sector, reaching over 54.7 million fish (95% CI; 37.6–74.1 million) and 636 mt (95% CI; ~510–

770 mt) in 2014 and over 35.3 million fish (95% CI; 23.1–50.4 million) and 361 mt (95% CI; 

~271–380 mt) in 2015 (Table A3, as cited in Gustafson et al. 2017). As in the Washington 

sector, bycatch ratios in the Oregon sector, (measured as both kg and numbers of eulachon per 

metric ton of retained ocean shrimp observed) also increased dramatically from 2011 to 2012, 

and remained high in 2013–2015 (Table A3, as cited in Gustafson et al. 2017). Observed bycatch 
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ratios were at their highest in 2014 (27.0 kg/mt and 2,232 eulachon/mt). In 2015, the Oregon 

sector bycatch ratios declined to 14.9 kg/mt and 1,458 eulachon/mt. 

Table 2-6. Numbers and weight of eulachon observed and bycatch ratios from ocean shrimp trawl vessels that 

landed their catch in Oregon (2010–2015). Bycatch ratios were calculated for each year by dividing the 

observed catch of eulachon (in numbers of eulachon and in kg of eulachon) by the observed weight (in mt) of 

retained ocean shrimp. A fleet-wide bycatch estimate (in both weight and number of fish) was obtained by 

multiplying the bycatch ratios by fleet-wide ocean shrimp landings. 95% bootstrapped confidence intervals 

(CI) are provided for the estimates. Asterisks (*) signify strata with fewer than three observed vessels.

Eulachon bycatch in the California ocean shrimp fishery followed a very different trajectory 

from that observed in Washington and Oregon during 2011–2013. Eulachon bycatch in 

California remained below 25 thousand fish from 2004 to 2008 (the fishery was not observed in 

2006), rose dramatically in 2010 to over 267 thousand (95% CI; 40,040–702,623) fish; fell to its 

lowest observed level of just 471 fish (95% CI; 198–827) in 2011, increased again dramatically 

in 2012 to over 337 thousand (95% CI; 148,647–606,034) fish, and then fell to just over 16 

thousand (95% CI; 3,816–33,998) fish in 2013 (Table A4, as cited Gustafson et al. 2017). 

Biomass of eulachon bycatch and bycatch ratios have shown similar fluctuations over the time 

period from 2010–2013 (Table A4, as cited Gustafson et al. 2017). Eulachon bycatch again 

increased from 2014–2015 in the California ocean shrimp trawl sector; estimated bycatch was 

over 611 thousand fish (95% CI; 241,491–1,063,825) and 6.6 mt in 2014 and increased to over 2 

million fish (95% CI; 960,061–3,567,063) and 32.3 mt in 2015 (Table A4, as cited Gustafson et 

al. 2017). The tonnage of observed ocean shrimp and of fleet-wide landings were relatively 

stable over from 2011–2015, indicating that yearly differences in eulachon distribution, or in the 

catchability of eulachon, likely contributed to the extreme fluctuations in eulachon bycatch in the 

California ocean shrimp fishery. Like Washington, but unlike Oregon, the bycatch ratio of 

eulachon increased from 2014 to 2015 in the California sector of the ocean shrimp trawl fishery. 
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The bycatch ratios in the California sector (measured as both kg and numbers of eulachon per 

metric ton of retained ocean shrimp observed) increased from 1.7 to 9.7 kg/mt shrimp and from 

159 to 594 eulachon/mt shrimp between 2014 and 2015 (Table A4, as cited Gustafson et al. 

2017).

Table 2-7. Numbers and weight of eulachon observed and bycatch ratios from ocean shrimp trawl vessels that 

landed their catch in California (2010–2015). Bycatch ratios were calculated for each year by dividing the 

observed catch of eulachon (in numbers of eulachon and in kg of eulachon) by the observed weight (in mt) of 

retained ocean shrimp. A fleet-wide bycatch estimate (in both weight and number of fish) was obtained by 

multiplying the bycatch ratios by fleet-wide ocean shrimp landings. 95% bootstrapped confidence intervals 

(CI) are provided for the estimates. Asterisks (*) signify strata with fewer than three observed vessels.

The combined estimates of the weight and number of eulachon caught in the Oregon and 

California ocean shrimp trawl fishery as bycatch from 2004–2015 (except for 2006 when these 

fisheries were not observed) and in Washington from 2010–2015 are presented in (Table A5, as 

cited in Gustafson et al. 2017). Total estimated bycatch of eulachon in the Oregon and California 

ocean shrimp fisheries ranged from nearly 158 thousand fish (95% CI; 11,642–492,887) in 2004 

to a high of nearly 959 thousand (95% CI; 237,377–2,169,745) fish in 2009. Estimated eulachon 

bycatch in the Washington ocean shrimp fishery in 2010 (its first year of observation) was nearly 

65 thousand fish, and the total 2010 estimated eulachon bycatch for all three states combined was 

over one million (95% CI; 540,065–1,889,846). Coastwide eulachon bycatch decreased to about 

605 thousand (95% CI; 397,957–876,346) fish in 2011 (Table A5, as cited in Gustafson et al. 

2017). However, as seen earlier, eulachon bycatch increased dramatically in all three states in 

2012, topping out at over 42.6 million (95% CI; ~26.8–58.8 million) individual eulachon. 

Bycatch increased again in Washington and Oregon, but not California in 2013, resulting in an 

estimated total eulachon bycatch for all three states combined of over 51.8 million fish (95% CI; 
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~31.8–73.9 million) (Table A5, as cited in Gustafson et al. 2017). Estimated weight of these 

bycaught eulachon in 2013 was over 743 mt (95% CI; ~603–967 mt) (Table A5). Coastwide 

eulachon bycatch in ocean shrimp trawl fisheries again increased in 2014 to an all-time high of 

68.8 million fish (95% CI; ~45.2–97.0 million) and 785 mt (95% CI; ~589–966 mt). In 2015, 

coastwide bycatch declined, relative to 2014, due to declining bycatch in the Oregon ocean 

shrimp sector; however, bycatch increased in both the Washington and the California sectors in 

2015 (Table A5, as cited in Gustafson et al. 2017). Estimated coastwide bycatch in 2015 

amounted to 59.8 million fish (95% CI; ~40.9–83.0 million) and 613 mt (95% CI; ~482–716 mt) 

(Table A5, as cited in Gustafson et al. 2017). Bycatch ratios were higher in Washington than in 

the Oregon fishery in both 2012 and 2013 (Tables A2–A3, Fig. A2, as cited in Gustafson et al. 

2017). In 2015, bycatch ratios declined in the Oregon sector but rose in both the Washington and 

California sectors of the ocean shrimp trawl fishery (Gustafson et al. 2017).

Table 2-8. Total estimated bycatch of eulachon (number of individuals and mt) in ocean shrimp fisheries 

observed by the West Coast Groundfish Observer Program from 2004-2015. Ocean shrimp fisheries were not 

observed in 2006 (Gustafson et al. 2017).

Collateral BRD Mortality

Although data on survivability of BRDs by small pelagic fishes such as eulachon are scarce, 

many studies on other fishes indicate that “among some species groups, such as small-sized 

pelagic fish, mortality may be high” and “the smallest escapees often appear the most 

vulnerable” (Suuronen 2005, p. 13–14; as cited in Gustafson et al. 2010). Results of several 
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studies have shown a direct relationship between length and survival of fish escaping trawl nets, 

either with or without deflecting grids (Sangster et al. 1996, Suuronen et al. 1996, Ingólfsson et 

al. 2007; as cited in Gustafson et al. 2010), indicating that smaller fish with their poorer 

swimming ability and endurance may be more likely to suffer greater injury and stress during 

their escape from trawl gear than larger fish (Broadhurst et al. 2006, Ingólfsson et al. 2007; as 

cited in Gustafson et al. 2010). A recent workshop (Pickard and Marmorek 2007, p. 31–33; as 

cited in Gustafson et al. 2010) to determine research priorities for eulachon in Canada 

recommended the need to research the effectiveness of BRDs and the need to estimate mortality, 

not just bycatch. 

Hannah and Jones (2012) used underwater video technology to examine behavior of eulachon 

when encountering rigid-grate BRDs in an ocean shrimp trawl net. The purpose of this research 

was to determine fish condition and survival following exclusion by the BRDs and the 

effectiveness of these types of BRDs at reducing mortality rates. Hannah and Jones (2012) 

stated that:

Almost 80% of the large eulachon maintained an upright vertical orientation throughout 

their escape and exited the trawl in a forward-swimming orientation. Large eulachon 

maintained distance from the deflecting grid better than the other species encountered (P 

< 0.001) and typically showed no contact or only minimal contact with it (63%). Only 

about 20–30% of the large eulachon showed behaviors indicating fatigue, such as laying 

on or sliding along the grid. 

Hannah and Jones (2012) concluded that:

...data on behavior of large eulachon escaping from a shrimp trawl show that most have 

enough residual swimming ability to minimize their physical contact with the deflecting 

grid, maintain their vertical orientation and to continue actively swimming in a forward 

direction as they exit. This suggests that the use of deflecting grids in the ocean shrimp 

fishery is likely reducing eulachon mortality rates, as well as bycatch.

It is unclear why bycatch ratios were highest in the Washington, intermediate in the Oregon, and 

lowest in the California sectors of the ocean shrimp trawl fishery in 2012 and 2013. The sharp

increases in the level of eulachon bycatch in both the Washington and Oregon ocean shrimp 

trawl fisheries in 2012 and 2013 occurred in spite of regulations, enacted in 2012, requiring the 

use of BRDs with a minimum 19 mm (0.75 inch) bar spacing. In 2014, eulachon bycatch ratios 

declined in Washington, but increased in both the Oregon and California sectors of the ocean 

shrimp trawl fishery. In 2015, both eulachon bycatch ratios and overall bycatch increased in both 

the Washington and California sectors of the ocean shrimp trawl fishery, but declined in the 

Oregon sector. Some of these patterns may be influenced by the degree to which artificial lights 

have been used to illuminate portions of trawl nets in different sectors of these fisheries. 
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Bycatch Reduction Efforts

Reducing bycatch in this fishery has long been an active field of research (Hannah et al. 1996, 

2003, 2011, 2015; Hannah and Jones 2000, 2003, 2007, 2012; Frimodig et al. 2009; as cited in 

Gustafson et al. 2017) and great progress has been made in reducing bycatch, particularly for 

larger-bodied fishes. Use of BRDs in offshore shrimp trawl fisheries, which was mandated 

beginning in 2002 in California and 2003 in Washington and Oregon has substantially reduced 

bycatch of fin fish in these fisheries (Hannah and Jones 2007, Frimodig et al. 2009; as cited in 

Gustafson et al. 2017). As of 2005, following required implementation of BRDs, the total 

bycatch by weight had been reduced to about 7.5% of the total catch (Hannah and Jones 2007). 

However, some of these studies were done at a time (mid 2000s) when eulachon were at a 

historically low level of abundance. 

None of the shrimp trawl BRDs in use today eliminate all incidental catch, and residual bycatch 

of fish (Hannah et al. 2011), especially of eulachon, remains a problem. Recent experimentation 

with artificial light to illuminate portions of trawl nets in the Oregon ocean shrimp fishery has 

shown great promise for significantly reducing bycatch of eulachon (Hannah and Jones 2014, 

2015; Hannah et al. 2015; Groth et al. 2017; as cited in Gustafson et al. 2017). In 2014, 

researchers compared bycatch levels (Figures 2-7 and 2-8) over 42 paired trials between lighted 

and unlighted trawl nets using double-rigged vessels that could tow paired shrimp trawl nets 

(Hannah et al. 2015). When 10 green LED lights were placed along the trawl fishing line of 

ocean shrimp trawl nets with rigid-grate BRDs with 0.75 inch (19.1 mm) bar spacing installed 

and then were compared with identical trawls nets without lights, the bycatch of eulachon was 

reduced by 91%, with little or no effect on shrimp catch. Hannah et al. (2015, p. 60, as cited in 

Gustafson et al. 2017) stated that “How the addition of artificial light is causing these changes in 

fish behavior and bycatch reduction is not known,” but the authors speculated that illumination 

of the trawl fishing line may possibly allow the fish to see the approaching net sooner and react 

in time to avoid being entrained, and “likely encouraged some species to also move downwards, 

perhaps exploiting a natural tendency to move towards the seafloor when threatened” (Hannah et 

al. 2015, p. 66, as cited in Gustafson et al. 2017). 
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Figure 2-7. Percent length frequency of eulachon (total length, mm) captured in ocean shrimp trawl nets with 

and without 1–4 LED lights attached in the vicinity of the bycatch reduction device (upper panel) and with 

and without 10 LED lights attached to the trawl fishing line (lower panel). (Hannah et al. 2015).
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Figure 2-8. Haul-by-haul comparison of the catch of eulachon (kg) in the two nets of a double-rigged shrimp 

trawl vessel with one side incorporating 10 LED lights on the fishing line and the other acting as a control. 

The ratio of control/treatment catch is also shown (solid line). Label “P” or “S” denotes the side of trawl gear 

(port or starboard) used as the control net (Hannah et al. 2015).

Hannah and Jones (2016, p. 6, as cited in Gustafson et al. 2017) stated that to their knowledge 

“all shrimpers that fished in 2015 [in the Oregon ocean shrimp fishery] used LED (Light 

Emitting Diode) lights when trawling” and that “all said they used lights and were happy with 

the resulting bycatch reduction.” Hannah and Jones (2016, as cited in Gustafson et al. 2017) also 

discussed several technical developments concerning types of lights that have been used and 

lighting configurations that are being tried to increase eulachon avoidance of shrimp trawl nets. 

Although use of LED lights on ocean shrimp trawl nets is not currently regulated in U.S. waters, 

Hannah and Jones (2016, p. 9, as cited in Gustafson et al. 2017) proposed regulations in Oregon 

be imposed to require use of footrope lighting devices such as the “Lindgren-Pitman Electralume 

Light Emitting Diode (LED) lights” or “other footrope lighting devices that are deemed by the 

Department to have comparable or greater total illumination may be approved for use, on a caseby-case basis, through issuance of an Experimental Gear Permit (EGP).”

According to Groth et al. (2017, p. 11, as cited in Gustafson et al. 2017), “NMFS observer data 

from 2015 showed that of the 2,137 hauls observed [in the Oregon sector]: 1,466 used LEDs, 66 

did not use LEDs, and on the 605 remaining hauls, this data was not reported.” Thus a minimum 

of about 69% of hauls in Oregon had some form of lights installed on the trawl nets in 2015. 

Furthermore, Groth et al. (2017, p. 11, as cited in Gustafson et al. 2017) stated that, “In 2016, we 

talked to 66 vessels landing shrimp into Oregon; of these, 57 vessels reported using LEDs 100% 

of the time, 7 reported using them sometimes (depending on bycatch rates, deferred maintenance 

cost, etc.), and 2 reported not using them at all.” Groth et al. (2017, p. 9 and 12, as cited in 

Gustafson et al. 2017) emphasized “that proper installation of LEDs is key to bycatch reduction” 
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and that research efforts in 2017 “will further examine use of LEDs in bycatch reduction.” 

According to Groth et al. (2017, p. 9, as cited in Gustafson et al. 2017), ODFW experiments 

planned for up to 16 days at sea in 2017, in collaboration with the Pacific States Marine Fisheries 

Commission.

Bycatch Hotspots 

Ward et al. (2015, as cited in Gustafson et al. 2017) applied spatiotemporal models to both 

fishery-dependent observations of eulachon bycatch and eulachon fisheries-independent survey 

data to 1) estimate population trends of eulachon, 2) understand eulachon bycatch risk in shrimp 

fisheries, and 3) identify persistent bycatch hotspots that may be used in future management 

actions to reduce eulachon bycatch rates. Two spatial data sets for the period from 2007–2012 

were examined: WCGOP catch data of shrimp and eulachon in the California, Oregon, and 

Washington ocean shrimp trawl fisheries and fishery-independent incidental eulachon catch in 

the West Coast Bottom Trawl Survey (Ward et al. 2015, as cited in Gustafson et al. 2017). Ward 

et al. (2015, as cited in Gustafson et al. 2017) found support for a greater than 40% annual 

increase in eulachon density based on the bycatch dataset and a greater than 55% annual increase 

based on the fisheries-independent survey dataset over the duration of the datasets. The later 

dataset also suggested that eulachon density was “substantially higher in 2012 than in any recent 

period” (Ward et al. 2015, as cited in Gustafson et al. 2017). These data also imply “that 

increases in bycatch [are] not due to an increase in incidental targeting of eulachon by fishing 

vessels, but likely because of an increasing population size of eulachon.” Ward et al. (2015, as 

cited in Gustafson et al. 2017) found that the coastal areas just south of Coos Bay, Oregon; 

between the Columbia River and Grays Harbor, Washington; and just south of La Push, 

Washington were consistent hotspots of eulachon bycatch across years. 

Summary: Bycatch-Shrimp Fishery

Although the use of bycatch reduction devices clearly are beneficial to eulachon, without a better 

understanding of bycatch as a proportion of eulachon in the marine environment, and its impact 

on recruitment, it is impossible to quantify the benefit. Nonetheless, NMFS acknowledges that 

the use of bycatch reduction devices represents a significant step in bycatch reduction and the 

threat bycatch poses to the persistence of eulachon.

Bycatch—Groundfish Fishery—The Pacific Ocean shore-based limited entry (LE)

groundfish trawl fishery was established in 1994 for midwater and bottom trawl gear and 

operates year-round off the coasts of Washington, Oregon, and southward to Morro Bay in 

California (Gustafson et al. 2017). Groundfish trawl vessels deliver their permitted and 

marketable catch to shore-side processors, and the majority of the portion of their catch which is 

prohibited by regulations or that is unmarketable is discarded at sea. The Individual Fishing 

Quota (IFQ) program for the limited entry shore-based bottom trawl fleet was implemented in 

2011, under the West Coast Groundfish Trawl Catch Share Program. This catch shares system 
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divides the portion of the trawl fisheries annual catch limits (ACL) for various groundfish stocks 

and stock complexes into shares controlled by individual fishermen or groups of fishermen 

(cooperatives), which can be harvested at the fishermen's discretion. In 2011, the LE trawl sector 

became a catch share program with 100% NMFS-certified observer. In 2015, exempted fishing 

permits (EFP) were issued for a subset of the fleet to carry electronic monitoring (EM) systems 

for compliance and quota management rather than observers; these vessels are still required to 

carry an observer for additional scientific data collection on ~ 20 to 30% of trips. 

Eulachon were not observed as bycatch in the LE bottom trawl fishery in Washington from 

2002–2010 (Gustafson et al 2017). From 2011 to 2015, a total of 442 individual eulachon were 

estimated as fleet-wide bycatch in the Washington IFQ non-hake bottom and midwater trawl

fishery (Gustafson et al 2017). However, no eulachon were observed or estimated as bycatch in 

the Washington sector in 2015. Within the Oregon portion of the LE bottom trawl fishery, 

eulachon bycatch occurred in four of the nine years from 2002–2010 with 80% (783/974) of this 

estimated bycatch occurring in the year 2002 (Gustafson et al 2017). However, no eulachon 

bycatch was recorded in the Oregon LE bottom trawl fishery in 2004, 2005, 2006, 2008, or 2010 

(Gustafson et al 2017). Between 2011 and 2015, the Oregon IFQ bottom trawl fishery had an 

estimated eulachon bycatch of 3,972 individual fish with nearly 63% (2,516 individuals) of this 

total occurring in the year 2014 (Gustafson et al 2017). Eulachon bycatch in the Oregon sector 

declined from a high point in 2014 to an estimated 641fish during 2015 (Gustafson et al. 2017). 

Eulachon were rarely caught in the California LE bottom trawl fishery; 5 fish in 2004 and 22 fish 

in 2010 (Gustafson et al. 2017). Not a single eulachon was recorded as bycatch in the California 

IFQ bottom and midwater trawl fishery from 2011–2014. Eulachon bycatch in this California 

sector in 2015, consisted of an estimated 2 total fish. 

Eulachon were encountered sporadically in the at-sea Pacific hake fishery as bycatch. The at-sea 

catcher-processor sector of the Pacific hake fishery has caught more eulachon than other at-sea 

Pacific hake sectors (Gustafson et al 2017). No eulachon bycatch was reported in the catcherprocessor sector from 2002–2005, or in 2010. The estimated eulachon bycatch in the catcherprocessor sector was 147; 1,268; and 242 fish in 2006, 2011, and 2014, respectively (Gustafson 

et al 2017). The bycatch estimate in 2011 amounted to 69% of the total eulachon bycatch 

estimate of 1,841 fish between 2002 and 2015. In all other years fewer than 40 individual 

eulachon were observed in the catcher-processor Pacific hake sector as bycatch, except for 2015 

when an estimated 56 fish were caught (Gustafson et al 2017).

The non-tribal mothership Pacific hake sector had a total estimated eulachon bycatch of 379 

individual fish between 2002 and 2015, with 73% of this bycatch occurring in 2013 (277 fish). 

No eulachon bycatch occurred in 2002–2006 or in 2010 or 2015, and fewer than 10 individual 

fish were estimated caught in 2007, 2008, 2009 and 2012 (Gustafson et al. 2017). Eulachon 

bycatch estimate in the tribal mothership Pacific hake fishery was 32 fish in 2009 and 160 fish in 

2011. Eulachon bycatch was not observed in this sector from 2002–2008 or in 2010. The tribal 
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mothership sector did not participate in the Pacific hake fishery in 2013–2015, and fewer than 

three vessels were observed in 2012 (Gustafson et al 2017).

In 2015, the shoreside midwater sector of the IFQ Pacific hake fishery was reported separately as 

either a midwater Pacific hake sector or as a midwater rockfish sector. When more than 50% of a 

vessel’s landings on a day were Pacific hake, the vessel's landing were reported as midwater 

hake; when landings were less than 50% hake by weight, the vessel’s landings were reported in 

the midwater rockfish sector. No recorded eulachon bycatch occurred in either the midwater 

hake or the midwater rockfish sectors in 2015 (Gustafson et al 2017).

A summary of eulachon bycatch in all U.S. west coast groundfish fisheries observed by the 

WCGOP and the A-SHOP that reported eulachon catch from 2002–2015 is provided in Table 

2-9. From 2002–2015, all groundfish sectors caught an estimated 11,968 individual eulachon. 

About 89% of this bycatch of eulachon occurred during 2011–2015, when efforts to identify 

eulachon in the bycatch of these fisheries became a priority and when other indices of eulachon 

abundance were highly positive.

Table 2-9. Estimated bycatch of eulachon (number of individual fish) in U.S. west coast groundfish fisheries 

that were observed by the West Coast Groundfish Observer Program (WCGOP) and the At-Sea Hake 

Observer Program (A- SHOP) from 2002–2015 (Gustafson et al. 2017).
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Conclusion 

Based on this information, the threat occurs at a moderate to high severity for the ocean shrimp 

fisheries, and occurs at a very low severity for the U.S. west coast groundfish fisheries, with a 

medium-to-high level of uncertainty. Thus, the relative impact to recovery is ranked high. 

Threat—Competition

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 9 12 12 9

BRT Threat Severity Low Low Low Low

Listing Factor E E E E

The following is a summary of competition-related effects on eulachon based on Gustafson et al. 

(2010).

Competition 

Competition is a natural process that helped shape the abundance of eulachon throughout their 

evolutionary history. The pressures of natural selection on eulachon promoted development of an 

array of life history strategies, involving differences in migration timing and habitat usage, so 

that populations could avoid competing for limited spatial and food resources and, ultimately, 

maximize their marine survival. Euphausiids (principally Thysanoessa spiniferia and Euphausia 

pacifica) are a primary prey item of eulachon in the open ocean and are also eaten by many other 

competing species. Tanasichuk et al. (1991, as cited in Gustafson et al. 2010) showed that 

euphausiids were the most important prey for both spiny dogfish and Pacific hake off the lower 

west coast of Vancouver Island. Livingston (1983) determined that euphausiids constituted 72% 

and 90% of the diet by weight of Pacific hake examined off Oregon and Washington, 

respectively, in 1967, and 97% of the diet by weight of Pacific hake 350–449 mm long off 

Oregon in 1980. Similarly, Outram and Haegele (1972) indicated that euphausiids were the most 

numerous prey items of Pacific hake off the British Columbia coast in 1970, occurring in 94% of 

Pacific hake stomachs analyzed. Rexstad and Pikitch (1986, p. 955; as cited in Gustafson et al. 

2010) stated that “euphausiids constitute the primary source of food for Pacific hake in the North 

Pacific.” The offshore Pacific hake stock migrates northward from winter spawning grounds to 

feed off the coast of the Pacific Northwest in the summer. This stock represents the largest 

component of the offshore pelagic fish biomass in the California Current system (Ware and 

McFarlane 1995, as cited in Gustafson et al. 2010). Recent evidence (Benson et al. 2002, Cooke 

et al. 2006, and Phillips et al. 2007; as cited in Gustafson et al. 2010) indicates that Pacific hake 

spawning may be shifting further north within the northern California Current system. This 

places more young of the year Pacific hake in that ecosystem (Phillips et al. 2007, as cited in 

Gustafson et al. 2010) in direct competition with eulachon for their preferred prey, euphausiids. 
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Euphausiid Fisheries 

A commercial fishery for euphausiids (also known as krill) occurs in the British Columbia 

portion of the Strait of Georgia (DFO 2007b, as cited in Gustafson et al. 2010). According to 

DFO (2007b, p. 6), euphausiid biomass in British Columbia waters “is dominated by five 

[species]: Euphausia pacifica, Thysanoessa spinifera, T. inspinata, T. longipes and T. raschii,”

and E. pacifica accounts for 70–100% of the biomass in the Strait of Georgia. The Integrated 

Fisheries Management Plan for euphausiids limits annual total allowable catch (TAC) of 

euphausiids in the Strait of Georgia to 500 mt (DFO 2007b, as cited in Gustafson et al. 2010). 

DFO (2007b, p. 3 of its Appendix A; as cited in Gustafson et al. 2010) stated that this level of 

harvest is considered to “be conservative and sustainable” within the Strait of Georgia. Eulachon 

originating from rivers draining into the Strait of Georgia likely leave the strait for waters over 

the continental shelf prior to reaching a size where they would begin consuming euphausiids, and 

thus the impact of this euphausiid fishery on eulachon is expected to be minor. 

Conclusion 

Based on this information, the threat occurs at a low severity and there is a low level of 

uncertainty. Thus, the relative impact to recovery is ranked low. 

Threat—Nonindigenous Species

Subpopulation Klamath Columbia Fraser BC

BRT Ranking 12 15 15 13

BRT Threat Severity Very Low Low Very Very Low Very Low

Listing Factor E E E E

The following is a summary of nonindigenous species-related effects on eulachon based on 

Gustafson et al. (2010).

Nonindigenous Species 

Non-indigenous species (plant, animal, or microbe) may adversely affect ecosystems they 

invade. Potential impacts and risks of nonindigenous aquatic species to native fish species 

include increased predation, increased competition for habitats and food, alteration of food webs, 

and transmission of new diseases and parasites (ISAB 2008, as cited in Gustafson et al. 2010). 

The negative impact of nonindigenous species is recognized as one of the leading factors causing 

imperilment of native North American freshwater aquatic species (Lassuy 1995, ISAB 2008; as 

cited in Gustafson et al. 2010) and was listed as a factor leading to the extinction of 40 North 

America fish species and subspecies, representing a full 68% of those lost over the past 100 

years (Miller et al. 1989, as cited in Gustafson et al. 2010). NRC (2004, as cited in Gustafson et 

al. 2010) reported that 17 nonindigenous fish species inhabit the Klamath River basin, but their 

impact on eulachon has not been studied. Schade and Bonar (2005, as cited in Gustafson et al. 
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2010) estimated that the percent of total fish species that are nonnative in streams in California, 

Oregon and Washington, were 39.6%, 24.5%, and 18.4%, respectively.

Conclusion

Based on this information, the threat occurs at a very low severity and there is a low-to-medium 

level of uncertainty. Thus, the relative impact to recovery is ranked very low.

2. Conservation Actions

Eulachon are protected in the U.S. under the ESA (listed as threatened). In Canada, the Fraser 

River eulachon Designatable Unit (DU) and the Central Pacific Coast eulachon DU remain under 

consideration for listing as endangered under Canada’s Species at Risk Act (SARA). In the U.S. 

and Canada, several actions have been taken, both before and since their listing, to reduce 

impacts on the species and its habitats. The following is a list of significant actions taken to 

protect eulachon and/or advance eulachon conservation:

Ocean Shrimp Fisheries – Effective December 2010, the state of Oregon required all 

shrimpers fishing within the Oregon Fisheries Conservation Zone are required to use rigid-grate 

bycatch reduction devices. The state of Washington adopted rigid-grate BRD regulation effective 

in January 2012. The Oregon Fish and Wildlife Commission changed the administrative rules 

governing the use of BRDs in the pink shrimp fishery to reduce the bycatch of eulachon. The 

new rules require the use of rigid-grate BRDs with bar spacing no more than 1.0 inch starting in 

2011, and 0.75 inch beginning in 2012. Current 2014–2015 regulations in Washington and 

Oregon, adopted by both states in 2012, require ocean shrimp trawl fishery BRDs to consist of a 

rigid panel or grate of narrowly spaced bars (usually constructed of aluminum) with no gaps 

between the bars exceeding 0.75 inches (19.1 mm). Approved BRDs for use in the ocean shrimp 

fishery in California include: (1) rigid- or semi-rigid grate excluders consisting of vertical bars 

with no gaps between the bars exceeding 2 inches (50.8 mm); (2) soft-panel excluders, usually 

made of a soft mesh material “with individual meshes no large than 6 inches;” and (3) fisheye 

excluders, which have a forward facing escape opening that is maintained by a rigid frame.

Oregon Department of Fish and Wildlife - In 2014 the ODFW conducted research on 

eulachon using light emitting diode lights (LEDs) attached to fishing gear (pink shrimp fishery) 

to assess the potential to reduce bycatch of eulachon associated with the ocean shrimp fishery. In 

2015, NMFS observer data showed that of the 2,137 hauls observed, 1,466 used LEDs, 66 did 

not use LEDs, and on the 605 remaining hauls, use of LEDs was unreported. In 2016, 66 of 57 

vessels landing shrimp reported using LEDs 100% of the time, 7 reported using them sometimes, 

and 2 reported not using them at all (Gustafson et al. 2017). 

Department of Fisheries and Oceans, Canada  Since 1995 DFO has suspended 

commercial eulachon fisheries in the Fraser River; closed the shrimp fishery in Queen Charlotte 
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Sound; adopted “eulachon action levels” by DFO management that warn of possible shrimp 

fishing closures when cumulative eulachon bycatch level is reached; and required BRDs installed 

in shrimp trawls to reduce eulachon bycatch.

Department of Fisheries and Oceans, Canada  First Nations Fisheries: Aboriginal 

harvest for food, social and ceremonial purposes is authorized by communal licenses in the lower 

Fraser River; a total of eight bands may apply for licenses for small amounts of eulachon.

Department of Fisheries and Oceans, Canada  Recreational Fisheries: Recreational 

fishing for eulachon with dip nets, gillnets, minnow nets, or cast nets in fresh water, is prohibited 

throughout British Columbia. Recreational harvest of eulachon is also prohibited in all marine 

areas of British Columbia due to conservation concerns.

Department of Fisheries and Oceans, Canada  Commercial Fisheries: The commercial 

eulachon fishery remains closed in the Fraser River. However, there are currently 16 ZU 

(introduced) eulachon license eligibilities. 

Elwha River – In 2000, as part of a comprehensive restoration effort in the Elwha River 

basin, the Elwha and Glines Canyon dams were acquired by the federal government. In 2014, 

both dams were removed. These restoration actions likely have indirect benefits to eulachon, 

especially in the lower reach of the Elwha River via material influx that support spawning and 

incubation of eulachon.

Klamath River  Pending Congressional approval, the Iron Gate dam, Copco 1 dam, 

Copco 2 dam, and J.C. Boyle dam are scheduled to be removed in 202039.

Department of Fisheries and Oceans, Canada  Beginning in 1995 DFO has suspended 

dredging in the Fraser River during the eulachon spawning season.

Washington Department of Ecology  the Washington Department of Ecology has issued 

the U.S. Army Corps of Engineers 401 water quality certifications on their operations and 

maintenance dredging program for the Columbia River that includes measures to reduce impacts 

to eulachon in the Columbia River during the spawning season. 

Sandy River Dam Removal – In 2007 Marmot Dam was removed and the Little Sandy 

Dam was taken down in 2008, which should restore much of the Sandy River’s natural 

hydrology and result in significant sediment transport into the lower Sandy River where 

eulachon have spawned historically.

Habitat Restoration Projects  Habitat restoration projects, mostly for salmon and 

steelhead, continue to be implemented along the West Coast to improve freshwater and estuarine 

 

39 Congress has yet to pass a bill to authorize and fund the Klamath Accords.
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habitats. These restoration actions likely have indirect benefits to eulachon, especially restoration 

actions in estuarine habitats that provide material influx that support food web processes.

Fisheries Regulations 

U.S. Fishery  The states of Oregon and Washington enacted permanent rules prohibiting 

directed harvest of eulachon in recreational and commercial fisheries in the Columbia River and 

its tributaries; commercial fishing closed permanently effective December 1, 2010 and 

recreational fishing closed permanently effective January 1, 2011. On March 1, 2013, the state of 

California issued regulations prohibiting the take or possession of eulachon in recreational 

fisheries. In 2014, 2015, 2016, and 2017 the states of Oregon and Washington opened a limitedopportunity eulachon fishery to: (1) provide essential context for interpreting historical harvest 

data to better understand trends and variability in eulachon abundance; (2) filling critical 

information gaps such as the length and age structure of spawning eulachon, as well as the 

temporal and spatial distribution of the run; (3) supporting the cultural traditions of Northwest 

tribes who rely on eulachon as a seasonally important food source; and (4) providing a limited 

public and commercial opportunity for eulachon harvest to maintain a connection between 

people and the eulachon resource. This connection is important to sustaining public engagement 

in eulachon conservation and recovery.

The exploitation rate for 2014 was 1.4% of the mean abundance estimate for the Columbia River 

subpopulation. The exploitation rate for 2015 was 2.8% of the mean abundance estimate for the 

Columbia River subpopulation. The exploitation rate for 2016 was 3.0% of the mean abundance 

estimate for the Columbia River subpopulation. The exploitation rate for 2017 was 0.5% of the 

mean abundance estimate for the Columbia River subpopulation. These exploitation rates are 

significantly lower than historical rates, which averaged 11.3% (low of 0.4% and high of 36.2%) 

prior to the listing40 of eulachon in 2010.

Pacific Fishery Management Council - in 2015 the Pacific Fishery Management Council 

adopted a Fishery Ecosystem Plan. As part of FEP, no directed fishery on eulachon in marine 

waters would be allowed without a NMFS-approved Fishery Management Plan.

Chapter 3. Recovery Goals, Objectives, and Delisting Criteria

This section describes the recovery goals, objectives, and delisting criteria that NMFS will use in 

future ESA status reviews of the southern DPS of eulachon. These reviews will contribute to 

NMFS’ larger objective of delisting the southern DPS of eulachon.

The recovery goals that are incorporated into a recovery plan may include delisting, 

reclassification (e.g., from endangered to threatened), and/or other “broad sense” goals that may 

go beyond the requirements for delisting to acknowledge social, cultural, or economic values 

 

40 Based on data in Figure 2-4 for the years 2000-2010.
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regarding the listed species. Delisting criteria must meet ESA requirements, while recovery may 

be defined more broadly. The ESA requires that recovery plans, to the maximum extent 

practicable, incorporate objective, measurable criteria which, when met, would result in a 

determination in accordance with the provisions of the ESA that the species should be removed 

from the Federal List of Endangered and Threatened Wildlife and Plants (50 CFR 17.11 and 

17.12; 50 CFR 223.102 and 224.101). These criteria are of two kinds: the biological viability 

criteria, which deal with population or demographic parameters, and the “threats” criteria, which 

relate to the five listing factors detailed in the ESA. The threats criteria define the conditions 

under which the listing factors, or threats, can be considered to be addressed or mitigated. 

Together these make up the “objective, measurable criteria” required under section 4(f)(1)(b) for 

the delisting decision. 

A. Recovery Goal

The goal of this Recovery Plan is to:

1. Increase the abundance and productivity of eulachon.

2. Protect and enhance the genetic, life history, and spatial diversity of eulachon 

throughout its geographical range; and

3. Reduce existing threats to warrant delisting of the species.

Figure ES-1 is a conceptual model that illustrates the linkages of the recovery strategy with the 

goal, objectives, delisting criteria, and actions.

B. Recovery Objectives and Delisting Criteria

Eulachon will no longer be in danger of extinction or likely to become endangered in the 

foreseeable future when all four subpopulations exhibit a combination of abundance and 

productivity sufficient to maintain genetic, life history, and spatial diversity across a range of 

conditions allowing for adaptation to changing environmental conditions; and threats have been 

addressed to an extent sufficient to maintain those biological characteristics throughout the 

foreseeable future.
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The recovery goal can be subdivided into discrete component objectives that, collectively, 

describe the conditions necessary for achieving the recovery goal. The Eulachon Recovery Team 

identified four recovery objectives:

1. Ensure subpopulation viability. 

2. Conserve spatial structure and temporal distribution patterns.

3. Conserve existing genetic and life history diversity and provide opportunities for 

interchange of genetic material between and within subpopulations.

4. Eliminate or sufficiently reduce the severity of threats.

The Eulachon Recovery Team identified four recovery objectives: 1) ensure subpopulation 

viability, 2) conserve spatial structure and temporal distribution patterns, 3) conserve existing 

genetic and life history diversity and provide opportunities for interchange of genetic material 

between and within subpopulations and, 4) eliminate or sufficiently reduce the severity of 

threats.

Figure 3-1. Recovery strategy conceptual model.
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In order to determine when recovery objectives have been met, we must provide objective, 

measurable criteria that can be applied to a determination that eulachon be removed from the 

Endangered Species List. Recovery criteria need to be established for each recovery objective 

and require evidence that the species’ status has improved to a point where it is viable. 

The delisting criteria are based on the best available scientific information and incorporate the 

most current understanding of the DPS and the threats it faces. As this recovery plan is 

implemented, additional information will become available that can increase certainty about 

whether the threats have been abated, whether improvements in subpopulation and DPS status 

have occurred, and whether linkages between threats and changes in eulachon status are 

understood. These delisting criteria will be assessed through an adaptive management program 

and NMFS may review whether the criteria may warrant revision during its five-year reviews of 

the ESU. As the biological status of eulachon improves over time, the ESA five-year status 

review process can be used to articulate the changes in viability parameters and ESA listing 

factors that might warrant a review of whether the DPS’s should be delisted. The five-year status 

review process will be used to evaluate this DPS's progress toward recovery and determine if any 

future change in ESA listing status is warranted.

There is much uncertainty in our knowledge regarding many of the anthropogenic and natural 

factors that could be limiting eulachon abundance and productivity. If we address the highest 

ranked threats and do not observe a positive response in the species’ demographics, then we may 

need to develop additional threat-based objectives and criteria. The proposed recovery approach 

serves to address the most pressing gaps in knowledge, addresses critical demographic factors 

required for recovery, and targets the reduction or elimination of threats so that the recovery 

objectives outlined in this plan have the greatest likelihood of being achieved. Because many of 

the threats to the recovery of eulachon are not directly manageable, the recovery strategy pursues 

simultaneous actions to address critical demographic factors, the range of threats, and knowledge 

gaps. Climate impacts on ocean conditions, i.e., as measured by large-scale spatial and temporal 

shifts in oceanic-atmospheric patterns in the northeast Pacific Ocean associated with both natural 

climate variability and anthropogenic-forced climate change, is likely the principal threat to 

eulachon, as it is the one phenomenon that correlates with the recent species-wide declines in 

abundance. Therefore, actions must be taken to understand the mechanisms by which these 

large-scale spatial and temporal shifts in oceanic-atmospheric patterns in the northeast Pacific 

Ocean affect eulachon productivity, recruitment, and persistence. 

The criteria are organized below according to (1) biological recovery criteria which address 

abundance, productivity, spatial structure, and genetic and life history diversity; and (2) 

qualitative/quantitative threat-based recovery criteria which address the threats impeding 

recovery.
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Recovery Objectives

The recovery goal can be subdivided into discrete component objectives that, collectively, 

describe the conditions necessary for achieving the recovery goal. The Eulachon Recovery Team 

identified four recovery objectives:

1. Ensure subpopulation viability. 

2. Conserve spatial structure and temporal distribution patterns.

3. Conserve existing genetic and life history diversity and provide opportunities for 

interchange of genetic material between and within subpopulations.

4. Eliminate or sufficiently reduce the severity of threats.

Delisting Criteria 

The ESA requires that recovery plans for listed species contain “measurable and objective 

criteria” that when met would result in the removal of the species from the endangered species 

list. To be removed from the list, a species needs to be no longer in danger of or threatened with 

extinction. Court rulings and NMFS policy indicate that delisting criteria must include both 

biological criteria and listing factor criteria that address the threats to a species (i.e., the five 

factors in ESA section 4[a][1][b]). The viability criteria relate most directly to the biological 

delisting criteria; however, they are not synonymous. NMFS establishes delisting criteria based 

on both science and policy considerations. For instance, science can identify the best metrics for 

assessing extinction risk and thresholds of those metrics associated with a given level of risk, but 

setting the acceptable level of risk for purposes of the ESA is a policy decision. 

1. Abundance: Each subpopulation is self-sustaining, i.e., each subpopulation has a less than 

5% probability of extinction in 100 years.

2. Productivity: Each subpopulation has a stable or increasing growth rate greater than 1 

across multiple generations.

3. Spatial Structure and Temporal Distribution: Eulachon subpopulations are distributed in a 

manner that insulates against loss from local catastrophic events and provides for recolonization of a subpopulation that is affected by such an event.

4. Genetic and Life History Diversity: Eulachon subpopulations exhibit high certainty that 

genetic and life history diversity is sufficient to sustain natural production across a range 

of conditions, and eulachon subpopulations exhibit high certainty that changes in 

phenotypical traits represent positive natural adaptations to prevailing environmental 

conditions.
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5. Threats: For each subpopulation, the threats listed in Table 2.2 have been 

diminished such that they do not limit attainment of the desired biological status 

of the DPS, and all the factors in section 4(a)(l) of the ESA have been addressed.
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Chapter 4. Recovery Strategy

Primary Focus and Justification of Recovery Strategy 

The purpose of this Recovery Plan is to identify a strategy for rebuilding and assuring the longterm viability of eulachon in the wild, allowing ultimately for the species’ removal from the 

Federal list of endangered and threatened species. 

There is much uncertainty in our knowledge regarding how threats (Table 2-2) influence 

eulachon. Nonetheless, we propose to work on what we can to advance the conservation of 

eulachon by working with our stakeholders to continue to implement actions that further reduce

the severity of threats to eulachon, as well as develop a comprehensive research program to 

collect the data to enable a greater understanding of eulachon population abundance and 

demographics, and improve our understanding of the impact that large-scale threats like climate 

change impacts on ocean conditions have on eulachon productivity, recruitment, and persistence. 

Historically, eulachon were a species’ with high abundances throughout its range. It is unclear 

whether undetected local extirpations may have already occurred, or if these declines are part of 

the species natural variability (intrinsically, eulachon exhibit considerable year-to-year 

variability) or a long-term shift in the species’ productivity induced by natural and/or 

anthropogenic forcing factors.

Threats to eulachon and their habitat must be sufficiently abated to ensure a high probability of 

survival into the future. The proposed recovery approach serves to address the most pressing 

gaps in knowledge, addresses critical demographic factors required for recovery, and targets the 

reduction or elimination of threats so that the recovery objectives outlined in this plan have the 

greatest likelihood of being achieved. Because many of the threats to the recovery of eulachon 

are not directly manageable, the recovery strategy pursues simultaneous actions to address 

critical demographic factors, the range of threats, and knowledge gaps. Climate impacts on ocean 

conditions, i.e., large-scale spatial and temporal shifts in oceanic-atmospheric patterns in the 

northeast Pacific Ocean associated with natural climate variability and anthropogenic-forced 

climate change, is likely the principal threat to eulachon, as it is the one phenomenon that offers 

a causative explanation for the recent species-wide declines in abundance. Therefore, actions 

must be taken to understanding these large-scale spatial and temporal shifts in oceanicatmospheric patterns in the northeast Pacific Ocean associated with natural climate variability 

and anthropogenic-forced climate change to identify the primary environmental forcing factors 

in the marine environment that influence eulachon productivity, recruitment, and persistence. 

This Recovery Plan covers the status, threats, recovery goals, objectives, and criteria for 

eulachon at the species’ scale. However, for the most part41, the recovery actions in this 

 

41 Due to the nature of the threats eulachon face, e.g., climate impacts on ocean conditions, as well as the distribution 

of eulachon in the marine environment, actions to address the species’ and the threats it faces will cross political 
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document are specific to eulachon subpopulations within the jurisdiction of the U.S. For the 

Fraser River and British Columbia Coast subpopulations, NMFS will, to the extent feasible, 

collaborate with DFO and First Nations in Canada to develop recovery actions to address threats 

to eulachon for the Fraser River and BC subpopulations. 

Chapter 5. Recovery Program

The Recovery Program for eulachon describes the recovery actions that are necessary to achieve 

the plan’s goals, objectives, and criteria. This section of the plan consists recovery actions and 

the implementation schedule. The recovery actions are organized around each of the recovery 

objectives, and the implementation schedule is a specific guide for carrying out recovery actions 

in terms of action priorities, action descriptions, duration of actions, and estimated costs. NMFS 

believes that the recovery plan should be a dynamic document that will change over time based 

on the progress of recovery and the availability of new information. As new information is 

obtained, additional actions will be identified and incorporated into the plan. As is the case for all 

recovery plans under the ESA, this plan will be regularly reviewed and the relative success of 

these actions in protecting eulachon assessed. 

Recovery Actions

ACTION 1: Establish a Eulachon Technical Recovery and Implementation Team 

1.1 Establish a eulachon technical recovery and implementation team to develop an overall 

framework for funding, prioritization, implementation, and reporting of recovery actions. 

ACTION 2: Implement Outreach and Education Strategies

2.1. Develop outreach and education strategies regarding the ecological, economic, and 

cultural values of eulachon; foster stewardship of the marine ecosystem; expand funding 

and research partnerships; and increase involvement of existing regional and international 

organizations.

ACTION 3: Near-Term Research Priorities

3.1. Conduct annual in-river spawning stock biomass surveys in spawning areas with a highto-moderate spawning frequency to develop long-term, high resolution abundance 

estimations for each subpopulation of eulachon.

3.2. Conduct a gap analysis to identify the data needs to develop a survey method to map 

eulachon spawning areas, with an emphasis on identifying core spawning areas, for each 

subpopulation.

 

jurisdictions. 
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3.2.1. Implement a high resolution mapping survey to identify core eulachon 

spawning areas for each subpopulation.

3.3. Conduct a gap analysis to identify the data needs to develop an at-sea survey method to 

create a reliable index of eulachon abundance in the marine environment.

3.3.1 Develop and implement an at-sea survey method to create a reliable index of 

eulachon abundance in the marine environment.

3.4. Conduct a gap analysis to identify the data needs to develop a genetic mixed stock 

baseline analysis of eulachon spawning subpopulations.

3.4.1. Conduct a genetic baseline analysis of eulachon spawning subpopulations to 

determine subpopulation-population structure of eulachon throughout the range of the 

DPS.

3.5. Conduct a gap analysis to identify the data needs to develop a genetic mixed stock 

baseline analysis of eulachon in the marine environment.

3.5.1 Conduct a genetic mixed stock baseline analysis of eulachon in the marine 

environment.

3.6. Conduct a gap analysis to identify the data needs to develop a method to correlate in-river 

and marine abundance estimations of eulachon. 

3.6.1. Conduct an analysis that correlates in-river and marine abundance estimations of 

eulachon. 

3.7. Conduct a gap analysis to identify the data needs to develop an ocean ecosystem 

indicators model of eulachon marine survival in the California Current Ecosystem.

3.7.1 Develop an ocean ecosystem indicators model of eulachon marine survival in the 

California Current Ecosystem to determine how short-term and long-term variability in 

ocean conditions affect eulachon abundance and productivity for each subpopulation.

3.8. Conduct a gap analysis to identify the data needs, e.g., age composition, length-weight 

relationship, intrinsic mortality rates, sex ratios, fecundity; necessary to parameterize a 

population viability analysis and develop abundance and productivity criteria for each 

subpopulation of eulachon.

3.8.1. Develop abundance and productivity criteria for each subpopulation of eulachon.
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ACTION 4: Conserve Spatial Structure and Temporal Distribution 

4.1. Develop a research and monitoring plan to determine the distribution (presence/absence) 

of eulachon in low-to-moderate frequency spawning areas by implementing an in-river 

sampling program, e.g., environmental DNA technology, to assess spatial distribution of 

eulachon in coastal watersheds of California, Oregon, and Washington.

ACTION 5: Eliminate or Sufficiently Reduce the Severity of Threats 

Marine Habitats

5.1. Conduct a gap analysis to identify the data needs to develop a plume-nearshore 

oceanographic model for the Columbia River subpopulation.

4.1.1 Develop a plume-nearshore oceanographic model to assess the relationship and 

significance of plume and nearshore ocean environments on eulachon survival, especially 

larval eulachon, during the freshwater-ocean transition period.

5.2. Develop a research plan to understand physiological requirements for survival (i.e. pH, 

temperature) and potential impacts of ocean acidification on eulachon larvae.

Bycatch

5.3. Develop a qualitative/quantitative recovery criterion through research and adaptive 

management. Based on the information gathered in conjunction with eulachon 5-year 

status reviews, we will evaluate and incorporate, as appropriate, the findings of on-going 

research on bycatch of eulachon in the ocean shrimp trawl fishery to develop a criterion 

based on a range of bycatch rates consistent with the recovery requirements of the 

species. 

5.4. Minimize bycatch of eulachon in the ocean shrimp fisheries by fleet-wide 

implementation of light emitting diode lights, rigid grate bycatch reduction devices, and 

additional gear-type or operational modifications, to further reduce bycatch of eulachon 

in the ocean shrimp trawl fisheries.

5.5. Develop a eulachon bycatch assessment model integrating in-river and marine abundance 

estimations of eulachon to analyze demographic information in order to determine 

changes in marine abundance and predict effects on freshwater productivity in response 

to bycatch in the ocean shrimp trawl fisheries.

Freshwater Habitats
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5.6. Conduct a gap analysis to identify freshwater habitats with multi-year high water 

temperatures that fall outside of the range of water temperatures that are optimal for 

eulachon spawning, incubation, and larval development. 

4.6.1. Develop site-specific recovery actions to restore or mitigate the impacts of high

water temperatures that impede eulachon spawning, incubation, and larval development. 

Predation

5.7. Conduct a gap analysis to identify the data needs to develop a research, monitoring, 

evaluation, and action plan to assess and reduce, where feasible, impacts of predation 

on eulachon in estuary and freshwater habitats.

4.7.1. Implement recovery actions to reduce high impact predator consumption rates of 

eulachon.

Dams/Water Diversions

5.8 Develop a qualitative/quantitative recovery criterion through research and adaptive 

management. Based on the information gathered in conjunction with eulachon 5-year 

status reviews, we will evaluate and incorporate, as appropriate, the findings of ongoing research on eulachon spawning areas affected by dams or channel-spanning 

water control structures to develop a criterion based on a range of recovery targets to 

maximize survival, growth, fitness, and development of eulachon larvae in the 

freshwater and plume-nearshore environment consistent with the recovery 

requirements of the species.

5.9 Develop a research and monitoring plan to monitor the effects of post-dam removal, e.g., 

sediment yields and water quality, in the Klamath River Basin to assess effects on the 

recruitment and recovery of eulachon.

5.10 Identify and implement actions to reduce the ecological effects caused by water 

management operations via dams and channel-spanning water control structures on 

eulachon riverine and estuarine habitats.

5.11 Investigate the long-term effects of the Toutle River Sediment Retention Structure on 

sedimentation processes in the Toutle, Cowlitz, and Columbia Rivers on eulachon 

habitat, as it relates to sediment and nutrient inputs into the estuary-plume environment 

and eulachon reproduction and survival in the freshwater environment.

5.12. Implement the monitoring and evaluation General Measures in the Northwest Power and 

Conversation Council’s Fish and Wildlife Program regarding changes in the hydrograph 
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associated with hydropower development and operations in the Columbia River, and 

impacts on eulachon survival and recovery.

5.12.1. Monitor and evaluate temporal and spatial species composition, abundance, and

foraging rates of juvenile eulachon predators at representative locations in the

estuary and plume.

5.12.2. Monitor, and evaluate the causal mechanisms, e.g., shifts in the timing,

magnitude, and duration of the hydrograph of the Columbia River, and

migration/behavior characteristics affecting survival of larval eulachon during

their first weeks in the plume-ocean environment.

5.12.3. Monitor and evaluate the ecological importance of the tidal freshwater, estuary,

plume, and nearshore ocean environments to the viability and recovery of the

Columbia River subpopulation of eulachon.

Water Quality, Disease, Competition, Shoreline Construction, Tribal/First Nations 

Fisheries, Recreation Harvest, Commercial Harvest, and Dredging

5.13. Develop qualitative/quantitative recovery criteria through research and adaptive 

management. Based on the information gathered in conjunction with eulachon 5-year 

status reviews, we will evaluate and incorporate, as appropriate, the findings of on-going 

research on water quality, disease, competition, shoreline construction, tribal/first nations 

fisheries, non-indigenous species, recreational harvest, commercial harvest, and dredging 

to develop criteria based on a range of targets consistent with the recovery requirements 

of the species. 

5.14. Water Quality: Develop a research and monitoring plan to identify contaminants of 

concern and sources to determine the significance of water quality degradation to 

eulachon and their habitats, and to inform the development of recovery actions and a 

recovery criterion through research and adaptive management.

5.15. Shoreline Construction: Evaluate the impacts of shoreline construction on eulachon and 

their habitats through research and adaptive management to inform the development of 

site-specific recovery actions.

5.15.1. Quantify the extent of shoreline construction in the Klamath River from 

river mile 10.7 to the confluence with the Pacific Ocean, and assess the 

severity of shoreline construction on the function of eulachon core

spawning areas.
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5.15.2. Quantify the extent of shoreline construction in the Umpqua River from 

river mile 39.0 to the confluence with the Pacific Ocean, and assess the 

severity of shoreline construction on the function of eulachon core

spawning areas.

5.15.3. Quantify the extent of shoreline construction in the Columbia River from 

river mile 146.1 to the confluence with the Pacific Ocean, and assess the 

severity of shoreline construction on the function of eulachon core

spawning areas.

5.15.4. Quantify the extent of shoreline construction in the Cowlitz River from 

river mile 80.8 the confluence with the Columbia River, and assess the 

severity of shoreline construction on the function of eulachon core

spawning areas.

5.15.5. Quantify the extent of shoreline construction in the Lewis River from river 

mile 31.1 the confluence with the Columbia River, and assess the severity 

of shoreline construction on the function of eulachon core spawning areas.

5.5.6. Quantify the extent of shoreline construction in the East Fork of the Lewis 

River from river mile 9.2 to the confluence with the Lewis River, and 

assess the severity of shoreline construction on the function of eulachon 

core spawning areas.

5.15.7. Develop site-specific recovery actions to eliminate, restore, or mitigate the 

impacts of shoreline construction that impede the function of eulachon 

core spawning areas. 

5.15.8. Implement site-specific recovery actions to eliminate, restore, or mitigate 

the impacts of shoreline construction that impede the function of eulachon 

core spawning areas. 

5.16. Implement a limited-opportunity eulachon fishery to: (1) provide essential context for 

interpreting historical harvest data to better understand trends and variability in eulachon 

abundance; (2) filling critical information gaps such as the length and age structure of 

spawning eulachon, as well as the temporal and spatial distribution of the run; (3) 

supporting the cultural traditions of Northwest tribes who rely on eulachon as a 

seasonally important food source; and (4) providing a limited public and commercial 

opportunity for eulachon harvest to maintain a connection between people and the 

eulachon resource. This connection is important to sustaining public engagement in 

eulachon conservation and recovery.

5.16.1. Tribal/First Nations Fisheries: Minimize impacts related to a directed fishery on 
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eulachon by developing and implementing an abundance-based fishery management and 

evaluation plan to ensure that exploitation rates do not negatively impact subpopulation 

productivity. 

5.16.2. Recreational Harvest: Minimize impacts related to a directed fishery on eulachon 

by developing and implementing an abundance-based fishery management and 

evaluation plan to ensure that exploitation rates do not negatively impact subpopulation 

productivity.

5.16.3. Commercial Harvest: Minimize impacts related to a directed fishery on eulachon 

by developing and implementing an abundance-based fishery management and 

evaluation plan to ensure that exploitation rates do not negatively impact subpopulation 

productivity.

5.17. Dredging: 

5.17.1. Develop a research, monitoring, and adaptive management plan to 

quantify the impacts of dredging and disposal activities associated with the 

Columbia River Navigation Channel Operations and Maintenance 

Dredging Program, including ocean dredged material disposal sites, on 

habitat forming and maintenance processes and the recruitment and 

recovery of eulachon.

5.17.2. Develop a research, monitoring, and adaptive management plan to 

quantify the impacts of dredging and disposal activities associated with the 

Umpqua River Navigation Channel Operations and Maintenance Dredging 

Program, including ocean dredged material disposal sites, on habitat 

forming and maintenance processes and the recruitment and recovery of 

eulachon.

5.17.3. Implement impact minimization measures to reduce the impacts of 

dredging and disposal activities associated with maintenance dredging 

programs—as well as the issuance of permits under section 404 of the 

Clean Water Act, Section 10 of the Rivers and Harbors Act, and state 

permits—including ocean dredged material disposal sites, on habitat 

forming and maintenance processes and eulachon.
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ACTION 6: Assess Regulatory Measures—Inadequacy of Existing Regulatory 

Mechanisms

6.1. Ensure appropriate and effective regulatory, response, restoration, and enforcement 

mechanisms are in place domestically and internationally for both planned and unplanned 

impacts. For planned impacts, project planning should ensure no net loss of eulachon 

critical habitat. Where natural or anthropogenic impacts do occur, an effective and 

complete response plan, including appropriate compensatory and site restoration, is 

executed.

ACTION 7: Develop a Research, Monitoring, Evaluation, and Adaptive 

Management Plan

In 2007, the NMFS Northwest Region (now the West Coast Region) released Adaptive 

Management for ESA-Listed Salmon and Steelhead Recovery: Decision Framework and 

Monitoring Guidance (NMFS 2007). This document describes the questions we ask in evaluating 

species status and making listing and delisting decisions. It offers conceptual-level guidance, not 

specific instructions, on gathering the information that will be most useful in tracking progress 

and assessing the status of listed species.

As outlined in the document, a delisting decision is based on evaluation of both the DPS’s

biological status and the extent to which the threats facing the DPS have been addressed. The

document spells out the questions that need to be answered through RME to satisfy the

requirements for each component of such a decision.

The document emphasizes that adaptive management is an experimental approach in which the 

assumptions underlying recovery strategies and actions are clearly stated and subject to 

evaluation (NMFS 2007). It further states that a monitoring and evaluation plan to support 

adaptive management should provide (1) a clear statement of the metrics and indicators by which 

progress toward achieving goals can be tracked, (2) a plan for tracking such metrics and 

indicators, and (3) a decision framework through which new information from monitoring and 

evaluation can be used to adjust strategies or actions aimed at achieving the plan’s goals.

The adaptive management guidance (NMFS 2007) discusses considerations for prioritizing 

monitoring and examines the consequences of different sorts of incomplete data. Management 

and delisting decisions often must be made with incomplete information. Different types of 

incomplete information pose correspondingly different types of risks for delisting decisions. This 

discussion is intended to help planners consider how their own implementation and monitoring 

decisions may affect our assessment of DPS status. In the Recovery Plan, we have adopted this 

Framework for eulachon.
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7.1. Develop an adaptive management plan to guide the recovery process by identifying key 

hypotheses, prioritizing research and monitoring, and evaluating alternative recovery 

strategies.

7.2. Develop a eulachon status and trend monitoring program.

7.3. Develop a recovery action effectiveness monitoring plan.

7.4. Develop an implementation and compliance monitoring plan.

7.5. Develop a monitoring plan to assess listing factors as they relate to eulachon recovery.

7.6 Conduct a retrospective analysis of land and water management impacts over time for 

eulachon spawning rivers where the data are available and compare to best estimates of 

eulachon abundance over time in the same rivers.

Figure 5-1. The adaptive management process. 
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Implementation Schedule and Costs

An implementation schedule is used to direct and monitor implementation and completion of 

recovery tasks. Recovery plan recovery action priorities in the third column of the following 

implementation schedule (Table 5-1) are assigned as follows:

Priority 1- Actions that must be taken to prevent extinction, including research actions to identify 

those actions that must be taken to prevent extinction.

Priority 2 - Actions that must be taken to prevent a significant decline in species 

population/habitat quality or in some other significant negative impact short of extinction. This 

includes research actions to identify those actions that must be taken to prevent such impacts.

Priority 3 - Remaining actions that must be taken to achieve delisting criteria, including 

monitoring to demonstrate achievement of demographic criteria.

Priority 4 - Actions necessary to facilitate post-delisting monitoring.

Priority 0 - All other actions that are not required for ESA recovery but that would advance 

broader goals beyond delisting.

Funding is estimated according to the number of years necessary to complete the task once 

implementation has begun, and does not account for inflation. Estimates are based on 

information available at the time this plan was finalized; the amount needed to actually complete 

the task may change as specific actions are pursued. The provision of cost estimates is not meant 

to imply that appropriate levels of funding will necessarily be available for all eulachon recovery 

tasks. The costs associated with the various recovery tasks listed below are for those to be 

implemented in U.S. waters only. Costs associated with promotion of international action have 

not been estimated.

The Implementation Schedule that follows outlines actions and estimated costs for the recovery 

program for eulachon, as set forth in the plan. It is a guide for meeting the recovery goals 

outlined in the plan. This schedule indicates action priorities, action numbers, action 

descriptions, duration of actions, and the parties responsible for the actions (either funding or 

carrying out) and estimated costs. Parties with authority, responsibility, or expressed interest to 

implement a specific recovery action are identified in the Implementation Schedule. The listing 

of a party in the Implementation Schedule does not require the identified party to implement the 

action(s) or to secure funding for implementing the actions(s).

This section includes a description of the recovery actions that, once implemented, should 

achieve the goal of recovering eulachon. Specifically, we will address the greatest threats for 

which recovery actions were deemed necessary to promote recovery of eulachon. These threats 

were ranked as high. If these recovery actions are fully implemented and recovery of eulachon is 

not achieved, then lower level threats will need to be addressed in the future.
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Implementation costs are organized by Recovery Action Number, Table 5-1.

Anticipated Date of Recovery

We estimated that it will take approximately 25 to 100 years for the southern DPS of eulachon to 

achieve recovery.

Total Cost of Recovery

NMFS has developed a set of recovery actions and cost estimates based on the best information 

currently available. With the many uncertainties involved in predicting the course of recovery 

and in estimating total costs, we focused on the first five years of implementation and in fiveyear intervals thereafter to coincide with our 5-year status reviews, with the understanding that 

before the end of each five-year implementation period, specific actions and costs will be 

estimated for subsequent years. Based on recovery actions for which we have cost estimates, the 

cost of implementation in the U.S. jurisdiction over the first 5 fiscal years is $12,205,000. A

gross estimate for the total cost of recovery actions to be implemented in the U.S jurisdiction is 

between $21,358,750 (25 years) to $32,038,125 (100 years). After the first 5 years, we will 

reevaluate the status of eulachon based on the information gathered over this period. It should be 

possible to make better informed projections about the time for and expense of recovery as more 

information is obtained.
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Table 5-1. Recovery Actions and Cost Estimates 

Recovery Action Priority Estimated Fiscal Year Costs (thousands of dollars)

Action

Number

Description Number FY1 FY2 FY3 FY4 FY5 Total 

Costs

1

1.1 Establish a eulachon technical recovery and 

implementation team to develop an overall 

framework for funding, implementation, and 

reporting of recovery actions. 

3 75 75 75 25 25 275

2

2.1 Develop outreach and education strategies regarding 

the ecological, economic, and cultural values of 

eulachon; foster stewardship of the marine 

ecosystem; expand funding and research 

partnerships; and increase involvement of existing 

3 50 50 50 50 50 250

regional and international organizations.

3

3.1 Conduct annual in-river spawning stock biomass 

surveys in spawning areas with high-to-moderate 

spawning frequency to develop long-term, high 

resolution abundance estimations for each 

3 325 325 250 250 250 1400

subpopulation of eulachon.

3.2 Conduct a gap analysis to identify the data needs to 

develop a survey method to map eulachon spawning 

areas, with an emphasis on identifying core spawning 

areas, for each subpopulation.

3 50 50 - - - 100

3.2.1 Implement a high resolution mapping survey to 

identify core eulachon spawning areas for each 

subpopulation.

3 - - 150 150 150 450

3.3 Conduct a gap analysis to identify the data needs to 

develop an at-sea survey method to create a reliable 

index of eulachon abundance in the marine 

3 75 75 - - - 150

environment.

3.3.1 Develop and implement an at-sea survey method to 

create a reliable index of eulachon abundance in the 

3 100 100 100 300

marine environment.
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

3.4 Conduct a gap analysis to identify the data needs to 

develop a genetic mixed stock baseline analysis of 

eulachon spawning subpopulations.

3 50 50 - - - 100

3.4.1 Conduct a genetic baseline analysis of eulachon 

spawning subpopulations to determine 

subpopulation-population structure of eulachon 

throughout the range of the DPS.

3 - - 75 75 25 200

3.5 Conduct a gap analysis to identify the data needs to 

develop a genetic mixed stock baseline analysis of 

eulachon in the marine environment.

3 50 50 - - - 100

3.5.1 Conduct a genetic mixed stock baseline analysis of 

eulachon in the marine environment.

3 - - 75 75 75 225

3.6 Conduct a gap analysis to identify the data needs to 

develop a method to correlate in-river and marine 

abundance estimations of eulachon.

3 75 75 - - - 150

3.6.1 Conduct an analysis that correlates in-river and 

marine abundance estimations of eulachon.

3 - - 100 75 75 205

3.7 Conduct a gap analysis to identify the data needs to 

develop an ocean ecosystem indicators model of 

eulachon marine survival in the California Current 

Ecosystem.

3 75 75 - - - 150

3.7.1 Develop an ocean ecosystem indicators model of 

eulachon marine survival in the California Current 

Ecosystem to determine how short-term and longterm variability in ocean conditions affect eulachon 

abundance and productivity for each subpopulation.

3 - - 125 125 125 375

3.8 Conduct a gap analysis to identify the data needs, 

e.g., age composition, length-weight relationship, 

intrinsic mortality rates, sex ratios, fecundity; 

necessary to parameterize a population viability 

analysis and develop abundance and productivity 

criteria for each subpopulation of eulachon.

3 75 75 - - - 150

3.8.1 Develop abundance and productivity criteria for each 

subpopulation of eulachon.

3 - - 125 125 125 375
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

3.9 Develop a research and monitoring plan to determine

the distribution (presence/absence) of eulachon in 

low-to-moderate frequency spawning areas by 

implementing an in-river sampling program, e.g., 

environmental DNA technology, to assess spatial 

distribution of eulachon in coastal watersheds of 

California, Oregon, and Washington.

3 60 60 60 60 60 300

4

4.1 Conduct a gap analysis to identify the data needs to 

develop a plume-nearshore oceanographic model for 

the Columbia River subpopulation.

3 75 75 - - - 150

5

5.1.1 Develop a plume-nearshore oceanographic model to 

assess the relationship and significance of plume and 

nearshore ocean environments on eulachon survival, 

especially larval eulachon, during the freshwaterocean transition period.

3 - - 125 125 125 375

5.2 Develop a research plan to understand physiological 

requirements for survival (i.e. pH, temperature) and 

potential impacts of ocean acidification on eulachon 

larvae. 

3 75 75 - - - 150

5.3 Develop qualitative/quantitative recovery criteria 

through research and adaptive management. Based 

on the information gathered in conjunction with 

eulachon 5-year status reviews, we will evaluate and 

incorporate, as appropriate, the findings of on-going 

research on bycatch of eulachon in the ocean shrimp 

fishery to develop a criterion based on a range of 

bycatch rates consistent with the recovery 

requirements of the species. 

3 - - - - - 50

5.4 Minimize bycatch of eulachon in the ocean shrimp 

fisheries by fleet-wide implementation of light 

emitting diode lights, rigid grate bycatch reduction 

devices, and additional gear-type or operational 

modifications, to further reduce bycatch of eulachon 

in the ocean shrimp trawl fisheries.

3 100 50 50 50 - 250
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

5.5 Develop a eulachon bycatch assessment model 

integrating in-river and marine abundance 

estimations of eulachon in order to analyze 

demographic information to determine changes in 

marine abundance and predict effects on freshwater 

productivity in response to bycatch in the ocean 

shrimp trawl fisheries.

3 - - 150 150 150 450

5.6 Conduct a gap analysis to identify freshwater habitats 

with multi-year high water temperatures that fall 

outside of the range of water temperatures that are 

optimal for eulachon spawning, incubation, and 

larval development.

3 50 50 - - - 100

5.6.1 Develop site-specific recovery actions to restore or 

mitigate the impacts of high water temperatures 

that impede eulachon spawning, incubation, and 

larval development. 

3 - - 75 75 75 225

5.7 Conduct a gap analysis to identify the data needs to 

develop a research, monitoring, evaluation, and 

action plan to assess and reduce, where feasible, 

impacts of predation on eulachon in estuary and 

freshwater habitats.

3 100 50 - - - 150

5.7.1 Implement recovery actions to reduce high impact 

predator consumption rates of eulachon.

3 - - 50 50 - 100

5.8 Develop a qualitative/quantitative recovery 

criterion through research and adaptive 

management. Based on the information gathered 

in conjunction with eulachon 5-year status 

reviews, we will evaluate and incorporate, as 

appropriate, the findings of on-going research on 

eulachon spawning areas affected by dams or 

channel-spanning water control structures to 

develop a criterion based on a range of recovery 

targets to maximize survival, growth, fitness, and 

development of eulachon larvae in the freshwater 

and plume-nearshore environment consistent with 

the recovery requirements of the species.

3 - - - - - 50
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

5.9 Develop a research and monitoring plan to 

monitor the effects of post-dam removal, e.g., 

sediment yields and water quality, in the Klamath 

River Basin to assess effects on the recruitment 

and recovery of eulachon.

3 25 25 25 25 25 125

5.10 Identify and implement actions to reduce the 

ecological effects caused by water management 

operations via dams and channel-spanning water 

control structures on eulachon riverine and 

estuarine habitats. 

3 100 100 100 100 100 500

5.11 Investigate the long-term effects of the Toutle 

River Sediment Retention Structure on 

sedimentation processes in the Toutle, Cowlitz, 

and Columbia Rivers on eulachon habitat, as it 

relates to sediment and nutrient inputs into the 

estuary-plume environment and eulachon 

reproduction and survival in the freshwater 

environment.

3 - 75 75 75 75 300

5.12 Implement the monitoring and evaluation General 

Measures in the Northwest Power and 

Conversation Council’s Fish and Wildlife Program

regarding changes in the hydrograph associated 

with hydropower development and operations in 

the Columbia River, and impacts on eulachon 

survival and recovery.

3 - - - - - TBD

5.12.1 Monitor and evaluate temporal and spatial species 

composition, abundance, and foraging rates of 

juvenile eulachon predators at representative 

locations in the estuary and plume.

3 - - - - - TBD

5.12.2 Monitor, and evaluate the causal mechanisms, e.g., 

shifts in the timing, magnitude, and duration of the 

hydrograph of the Columbia River, and 

migration/behavior characteristics affecting 

survival of larval eulachon during their first weeks 

in the plume-ocean environment.

3 - - - - - TBD
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

5.12.3 Monitor and evaluate the ecological importance of 

the tidal freshwater, estuary, plume, and nearshore 

ocean environments to the viability and recovery of 

the Columbia River subpopulation of eulachon.

3 - - - - - TBD

5.13 Develop qualitative/quantitative recovery criteria 

through research and adaptive management. Based 

on the information gathered in conjunction with 

eulachon 5-year status reviews, we will evaluate 

and incorporate, as appropriate, the findings of ongoing research on water quality, catastrophic 

events, disease, competition, shoreline 

construction, tribal/first nations fisheries, nonindigenous species, recreational harvest, 

commercial harvest, scientific monitoring, and 

dredging to develop criteria based on a range of 

targets consistent with the recovery requirements 

of the species.

3 - - - - - 50

5.14 Water Quality: Develop a research and monitoring 

plan to identify contaminants of concern and 

sources to determine the significance of water 

quality degradation to eulachon and their habitats, 

and to inform the development of recovery actions 

and a recovery criterion through research and 

adaptive management.

3 50 50 50 50 50 250

5.15 Shoreline Construction: Develop a research and 

monitoring plan to assess the impact of shoreline 

development on eulachon and their habitats to 

inform the development of site-specific recovery 

actions.

3 50 - - - - 100

5.15.1 Quantify the extent of shoreline construction in the 

Klamath River from river mile 10.7 to the 

confluence with the Pacific Ocean, and assess the 

severity of shoreline construction on the function 

of eulachon core spawning areas.

3 - 50 50 - - 100
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

5.15.2 Quantify the extent of shoreline construction in the 

Umpqua River from river mile 39.0 to the 

confluence with the Pacific Ocean, and assess the 

severity of shoreline construction on the function 

of eulachon core spawning areas.

3 - 50 50 - - 100

5.15.3 Quantify the extent of shoreline construction in the 

Columbia River from river mile 146.1 to the 

confluence with the Pacific Ocean, and assess the 

severity of shoreline construction on the function 

of eulachon core spawning areas.

3 - 50 50 - - 100

5.15.4 Quantify the extent of shoreline construction in the 

Cowlitz River from river mile 80.8 the confluence 

with the Columbia River, and assess the severity 

of shoreline construction on the function of 

eulachon core spawning areas.

3 - 50 50 - - 100

5.15.5 Quantify the extent of shoreline construction in the 

Lewis River from river mile 31.1 the confluence 

with the Columbia River, and assess the severity 

of shoreline construction on the function of 

eulachon core spawning areas.

3 - 50 50 - - 100

5.15.6 Quantify the extent of shoreline construction in the 

East Fork of the Lewis River from river mile 9.2 

to the confluence with the Lewis River, and assess 

the severity of shoreline construction on the 

function of eulachon core spawning areas.

3 - 50 50 - - 100

5.15.7 Develop site-specific recovery actions to 

eliminate, restore, or mitigate the impacts of 

shoreline construction that impede the function of 

eulachon core spawning areas. 

3 - - - 50 - 50

5.15.8 Implement site-specific recovery actions to 

eliminate, restore, or mitigate the impacts of 

shoreline construction that impede the function of 

eulachon core spawning areas. 

3 - - - - 500 500
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

5.16 Implement a limited-opportunity eulachon fishery 

to: (1) provide essential context for interpreting 

historical harvest data to better understand trends 

and variability in eulachon abundance; (2) filling 

critical information gaps such as the length and 

age structure of spawning eulachon, as well as the 

temporal and spatial distribution of the run; (3) 

supporting the cultural traditions of Northwest 

tribes who rely on eulachon as a seasonally 

important food source; and (4) providing a limited 

public and commercial opportunity for eulachon 

harvest to maintain a connection between people 

and the eulachon resource. This connection is 

important to sustaining public engagement in 

eulachon conservation and recovery.

3 - - - - - -

5.16.1 Tribal/First Nations Fisheries: Minimize impacts 

related to a directed fishery on eulachon by 

developing and implementing an abundance-based 

fishery management plan to ensure that 

exploitation rates do not negatively impact 

subpopulation productivity.

3 100 50 50 - - 200

5.16.2 Recreational Harvest: Minimize impacts related to 

a directed fishery on eulachon by developing and 

implementing an abundance-based fishery 

management plan to ensure that exploitation rates 

do not negatively impact subpopulation 

productivity.

3 100 50 50 - - 200

5.16.3 Commercial Harvest: Minimize impacts related to 

a directed fishery on eulachon by developing and 

implementing an abundance-based fishery 

management plan to ensure that exploitation rates 

do not negatively impact subpopulation 

productivity.

3 100 50 50 - - 200

5.17 Dredging: - - - - - -
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

5.17.1 Develop a research, monitoring, and adaptive 

management plan to quantify the impacts of 

dredging and disposal activities associated with 

the Columbia River Navigation Channel 

Operations and Maintenance Dredging Program, 

including ocean dredged material disposal sites, on 

habitat forming and maintenance processes and 

the recruitment and recovery of eulachon.

3 100 - - - - 100

5.17.2 Develop a research, monitoring, and adaptive 

management plan to quantify the impacts of 

dredging and disposal activities associated with 

the Umpqua River Navigation Channel Operations 

and Maintenance Dredging Program, including 

ocean dredged material disposal sites, on habitat 

forming and maintenance processes and the 

recruitment and recovery of eulachon.

3 100 - - - - 100

5.17.3 Implement impact minimization measures to reduce 

the impacts of dredging and disposal activities 

associated with maintenance dredging programs—as 

well as the issuance of permits under section 404 of 

the Clean Water Act, Section 10 of the Rivers and 

Harbors Act, and state permits—including ocean 

dredged material disposal sites, on habitat forming 

and maintenance processes and eulachon.

3 - 25 25 25 25 100

6

6.1 Ensure appropriate and effective regulatory, 

response, restoration, and enforcement mechanisms 

are in place domestically and internationally for both 

planned and unplanned impacts. For planned impacts, 

project planning should ensure no net loss of 

eulachon critical habitat. Where natural or 

anthropogenic impacts do occur, an effective and 

complete response plan, including appropriate 

compensatory and site restoration, is executed.

3 25 25 25 25 25 125

7
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Recovery 

Action

Number

Action 

Description

Priority 

Number

Estimated Fiscal Year Costs (thousands of dollars)

FY1 FY2 FY3 FY4 FY5 Total 

Costs

7.1 Develop an adaptive management plan to guide the 

recovery process by identifying key hypotheses, 

prioritizing research and monitoring, and evaluating 

alternative recovery strategies.

3 100 100 50 - - 250

7.2 Develop a eulachon status and trend monitoring 

program.

3 50 50 50 - - 150

7.3 Develop a recovery action effectiveness monitoring 

plan.

3 100 100 50 - - 250

7.4 Develop an implementation and compliance 

monitoring plan.

3 50 50 50 - - 150

7.5 Develop a monitoring plan to assess listing factors as 

they relate to eulachon recovery.

3 100 100 50 - - 250

7.6 Conduct a retrospective analysis of land and water 

management impacts over time for eulachon 

spawning rivers where the data are available and 

compare to best estimates of eulachon abundance 

over time in the same rivers.

3 - 100 100 100 50 350
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Literature Cited

Beacham, T. D., D. E. Hay, and K. D. Le. 2005. Population structure and stock identification of 

eulachon (Thaleichthys pacificus), an anadromous smelt, in the Pacific Northwest. Mar. 

Biotechnol. 7:363–372.

BPA (Bonneville Power Administration), U.S. Bureau of Reclamation, U.S. Army Corps of

Engineers. April 2001. The Columbia River System: Inside Story, second edition.

Federal Columbia River Power System.

Chiabai, R. 1978. Cowlitz River smelt sport dip net fishery total catch estimates. Washington 

Department of Fish and Wildlife. Memorandum.

Dalton, M., P. Mote, and A. Snover. 2013. Climate change in the Northwest: implications for

our landscapes, waters, and communities. Island Press, Washington, D.C. 230 p.

Elsner MM, Cuo L, Voisin N, Hamlet AF, Deems JS, Lettenmaier DP, Mickelson KEB, Lee SY. 

2009. Implications of 21st century climate change for the hydrology of Washintgon State. 

Washington Climate Change Impacts Assessment: Evaluating Washington’s future in a changing 

climate.

Fresh, K. L., E. Casillas, L. L. Johnson, and D. L. Bottom. 2005. Role of the estuary in the

recovery of Columbia River Basin salmon and steelhead: An evaluation of the effects of

selected factors on salmonid population viability. U.S. Department of Commerce, NOAA

Technical Memorandum NMFS-NWFSC-69, 105 p.

Gustafson, R.G., M.J. Ford, D. Teel, and J.S. Drake. 2010. Status review of eulachon 

(Thaleichthys pacificus) in Washington, Oregon, and California. U.S. Dept. Commerce. NOAA 

Tech. Memo. NMFS-NWFSC-105, 360 p.

Gustafson, R., Y.-W. Lee, E. Ward, K. Somers, V. Tuttle, and J. Jannot. 2015. Observed and 

estimated bycatch of eulachon in US west coast ocean shrimp trawl fisheries from 2004–2013 

(appendix to above report, 37 p.). 

Gustafson, R., L. Weitkamp, Y-W Lee, E.Ward, K. Somers,V. Tuttle, and J. Jannot. 2016. 

Status Review Update of Eulachon (Thaleichthys pacificus) Listed under the Endangered Species 

Act: Southern Distinct Population Segment.

Gustafson, R., Y.-W. Lee, E. Ward, K. Somers, V. Tuttle, J. Jannot, and J. McVeigh. 2017. 

Observed and estimated bycatch of eulachon in US west coast ocean shrimp trawl fisheries from 

2004–2015 (appendix to above report, 25 p.). 

Hannah, R. W., and S. A. Jones. 2012. Evaluating the behavioral impairment of escaping fish 

can help measure the effectiveness of bycatch reduction devices. Fisheries Research 131–133: 

39– 44.
E S A R e c o v e r y P l a n : S o u t h e r n D P S E u l a c h o n | 130

2017 | National Marine Fisheries Service

Hannah, R.W., Lomeli, M.J.M., and Jones, S.A. 2015. Tests of artificial light for bycatch 

reduction in an ocean shrimp (Pandalus jordani) trawl: Strong but opposite effects at the 

footrope and near the bycatch reduction device. Fisheries Research 170: 60-67.

Hart, J. L. 1973. Pacific fishes of Canada. Bull. Fish. Res. Board Can. 180.

Hay, D. E. and McCarter, P. B. 2000. Status of the eulachon Thaleichthys pacificus in Canada. 

Department of Fisheries and Oceans Canada, Canadian Stock Assessment Secretariat, Research 

Document 2000-145. Ottawa. 92 p.

Hay, D.E., P.B. McCarter, R. Joy, M. Thompson, and K. West. 2002. Fraser River eulachon 

biomass assessments and spawning distributions: 1995-2002. PSARC Working Paper P2002-08. 

60 p.

Hixon, M. A., S. Gregory, and W. D. Robinson. 2010. Oregon's fish and wildlife in a changing 

climate. In: K.D. Dello and P.W. Mote (eds). Oregon Climate Assessment Report. Oregon 

Climate Change Research Institute, College of Oceanic and Atmospheric Sciences, Oregon State 

University, Corvallis, OR.

Huntington, E. 1963. Reminiscences of Cowlitz County. Cowlitz County Hist. Q. 5(3):1–9.

ISAB (Independent Scientific Advisory Board). 2007. Climate change impacts on Columbia

River basin fish and wildlife. ISAB, Report 2007-2, Portland, Oregon.

Jackson, J. and Y.W. Cheng. 2001. Improving parameter estimation for daily egg production 

method of stock assessment of pink snapper in Shark Bay, Western Australia. Journal of 

Agricultural, Biological and Environmental Statistics 6:243-257.

Jay, D. A. and P. Naik. 2002. Separating human and climate impacts on Columbia

Riverhydrology and sediment transport. In: Southwest Washington Coastal Erosion

Workshop Report 2000, G. Gelfenbaum and G.M. Kaminsky, eds., USGS Open File

Report 02-229.

Kaukinen, K. H., K. J. Supernault, and K. M. Miller. 2004. Development of microsatellite loci in 

eulachon fish (Thaleichthys pacificus). Mol. Ecol. Notes 4:632–634.

Leopold, L.B. and Maddock, T. 1953. The hydraulic geometry of stream channels and some 

physiographic implications. U.S. Geological Survey, Professional Paper, 252, 56p.

Mantua, N.J., S.R. Hare, Y. Y. Zhang, J.M. Wallace and R.C. Francis. 1997. A Pacific 

interdecadal climate oscillation with impacts on salmon production. Bull. Amer. Meteor. Soc., 

78, 1069-1079.

Mantua, N.J. 2009. Patterns of change in climate and Pacific salmon production. American 

Fisheries Society, Symposium 70.
E S A R e c o v e r y P l a n : S o u t h e r n D P S E u l a c h o n | 131

2017 | National Marine Fisheries Service

McAllister, D. E. 1963. A revision of the smelt family, Osmeridae. Nat. Mus. Can., Biol. Ser. 71, 

Bull. 191:1–53.

McLean, J. E., D. E. Hay, and E. B. Taylor. 1999. Marine population structure in an anadromous 

fish: Life history influences patterns of mitochondrial DNA variation in the eulachon, 

Thaleichthys pacificus. Mol. Ecol. 8:S143–S158.

McLean, J. E., and Taylor, E. B. 2001. Resolution of population structure in a species with high 

gene flow: Microsatellite variation in the eulachon (Osmeridae: Thaleichthys pacificus). Mar. 

Biol. 139:411–420.

Mecklenburg, C. W., Mecklenburg, T. A., and Thorsteinson, L. K. 2002. Fishes of Alaska. 

American Fisheries Society.

Minckley, W. L., Hendrickson, D. A., and Bond, C. E. 1986. Geography of western North 

American freshwater fishes: Description and relationship to intracontinental tectonism. In The 

zoogeography of North American freshwater fishes, p. 519-613.

Mote, P.W., and Salathé Jr., E.P. 2009. Future climate in the Pacific Northwest. Washington 

Climate Change Impacts Assessment: Evaluating Washington’s future in a changing climate.

Moyle, P. B. 1976. Inland Fishes of California. University of California Press, Berkeley, 

California. 405 pp.

NMFS (National Marine Fisheries Service). 2007. Adaptive Management for ESA-Listed 

Salmon and Steelhead Recovery: Decision Framework and Monitoring Guidance. Prepared by 

National Marine Fisheries Service Northwest Region and Northwest Fisheries Science

Center. 

NMFS (National Marine Fisheries Service). 2014. Endangered Species Act Section 7(a)(2) 

supplemental biological opinion. Consultation on remand for operation of the Federal Columbia 

River Power System. 

Parker, K. 1985. Biomass model for the egg production method. P. 5-6 in: R. Lasker (editor). An 

egg production method for estimating spawning biomass of pelagic fish: application to the 

northern anchovy, Engraulis mordax. U.S. Department of Commerce, NOAA Technical Report 

36. Washington, D.C.

Poff, N. Leroy and Hart, David D. 2002. How dams vary and why it matters for emerging 

science of dam removal. BioScience 52: 659-668.

Richardson, J. 1836. Fauna boreali-Americana; or the zoology of the northern parts of British 

America. Part Third, The Fish. London: Richard Bentley. p. 226.

Salathé, Jr., E.P., Zhang Y, Leung, L.R, Qian, Y. 2009. Regional climate model projections for 

the State of Washington. Washington Climate Change Impacts Assessment: Evaluating 

Washington’s future in a changing climate.
E S A R e c o v e r y P l a n : S o u t h e r n D P S E u l a c h o n | 132

2017 | National Marine Fisheries Service

Scott, W. B., and Crossman, E. J. 1973. Freshwater fishes of Canada. Fisheries Research Board 

of Canada Bulletin No. 184:320-325.

Smith, W. E., and R. W. Saalfeld. 1955. Studies on Columbia River smelt Thaleichthys pacificus 

(Richardson). Washington Dept. Fisheries, Olympia. Fish. Res. Pap. 1(3):3–26.

USEPA (U.S. Environmental Protection Agency). 2003. EPA Region 10 Guidance for Pacific 

Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 

10 Office of Water, Seattle, WA.

WDFW and ODFW (Washington Department of Fish and Wildlife and Oregon Department of 

Fish and Wildlife). 2016. Progress Report: Studies of Eulachon in the Columbia River.

Willson, M. F., R. H. Armstrong, M. C. Hermans, and K Koski. 2006. Eulachon: a review of 

biology and an annotated bibliography. Alaska Fisheries Science Center Processed Report 2006-

12. Auke Bay Laboratory, Alaska Fish. Sci. Cent., NOAA, Natl. Mar, Fish. Serv., Juneau, AK.