January 11, 2024

U.S. Department of Commerce
Attn: Gina Raimondo
Secretary of Commerce
1401 Constitution Ave NW
Washington, DC 20230
TheSec@doc.gov

Delivered Electronically (1/11/24)

NOAA Fisheries Directorate
Attn: Janet Coit
Assistant Administrator for Fisheries
1315 East-West Highway, 14th Floor
Silver Spring MD 20910
janet.coit@noaa.gov

Dear Secretary Raimondo and Assistant Administrator Coit:

Pursuant to section 4(b) of the Endangered Species Act (“ESA”), Wild Fish Conservancy submits theattached Petition to List Alaskan Chinook salmon as a threatened or endangered species and todesignate critical habitat under the ESA. A formal notice letter regarding our request is included in
the petition.
Also attached is a copy of the notice letter that Petitioners delivered to the Alaska Department ofFish and Game (“ADF&G”) on May 24th, 2023, notifying ADF&G of our intent to file this petition.
The supporting materials for the petition can be found on the following webpage:https://drive.google.com/drive/folders/1ZPZaaH0t5QE6iQb1TBoNdvACyfytHgt_?usp=sharing
Please contact me if you have any issues accessing these documents.
Thank you,

Emma Helverson, Executive Director, Wild Fish Conservancy

emma@wildfishconservancy.org | 484-788-1174 | PO Box 402, Duvall, WA 98019

cc:
douglas.vincent-lang@alaska.gov, Douglas Vincent-Lang, Commissioner of the Alaska Departmentof Fish & Game
annemarie.eich@noaa.gov, Anne Marie Eich, Assistant Regional Administrator for Protected
Resources, Alaska Regional Office, NOAA Fisheries
melissa.hill@alaska.gov, Melissa Hill, Acting Director, Alaska Department of Fish and Wildlife

May 24, 2023
Doug Vincent-Lang
Commissioner of the Alaska Department of Fish and Game
P.O. Box 115526
1255 W. 8th Street
Juneau, AK 99811
Submitted Via Email: douglas.vincent-lang@alaska.gov
Dear Commissioner Vincent-Lang:
Pursuant to 50 C.F.R. § 424.14(b), we hereby provide notice that Wild Fish Conservancy intends to file apetition under the federal Endangered Species Act to list and designate critical habitat for Chinook Salmon(Oncorhynchus tshawytscha) in Southern Alaska, including Southeast and Southwest Alaska and Cooke
Inlet, no sooner than 30 days from the date that this notice is provided.
We understand this 30-day notice may no longer be legally required under the Endangered Species Act but
we are submitting as a courtesy as it is our intent to maintain open communication with the state of Alaska
through this petition process about our concerns over the health of Alaska Chinook populations.
Sincerely,

Emma Helverson
Executive Director
Wild Fish Conservancy
emma@wildfishconservancy.org
cc:
Melissa Hill, Acting Director, Alaska Department of Fish and Wildlife, melissa.hill@alaska.gov

Petition to Designate Evolutionary Significant Units and List Alaskan Chinook Salmon(Oncorhynchus tshawytscha) under the Endangered Species Act

Wild Fish Conservancy

January 11th, 2024

1

Table of Contents

Table of Contents

Executive Summary .................................................................................................................................. 3
Notice of Petition.....................................................................................................................................20
Legal Background.............................................................................................................................................. 21
Listing an ESU as an Endangered or Threatened........................................................................................................................22

Best Available Science Supports listing of at least one Alaskan ESU of Chinook Salmon ......22
Ecology and Biology of Southern Alaska Chinook Description............................................................. 23
Distribution ................................................................................................................................................................................................23
Life Cycle and Physiology ...................................................................................................................................................................24
Importance of age structure for Alaska Chinook.........................................................................................................................25
Habitat Requirements.............................................................................................................................................................................26
Diet................................................................................................................................................................................................................30
Natural Mortality .....................................................................................................................................................................................30
Taxonomy...................................................................................................................................................................................................31
Population Structure and Significance of Life History Variation .........................................................................................31

Status .........................................................................................................................................................33
Historical baseline.............................................................................................................................................. 33
Basin Summaries of Population Status and Threats ................................................................................ 34
Southern Aleutian Island Watersheds..............................................................................................................................................34
Cook Inlet Populations ..........................................................................................................................................................................34
Alexander Creek.......................................................................................................................................................................................34
Theodore River.........................................................................................................................................................................................34
Unuk River.................................................................................................................................................................................................35
Chickamin River ......................................................................................................................................................................................36
Stikine River..............................................................................................................................................................................................36
Andrew Creek ...........................................................................................................................................................................................37
Chilcat River..............................................................................................................................................................................................37
King Salmon River. ................................................................................................................................................................................38
Taku River..................................................................................................................................................................................................39
Situk River..................................................................................................................................................................................................39
Alsek River.................................................................................................................................................................................................40
Karluk River ..............................................................................................................................................................................................40

Threats to the Species .............................................................................................................................41
Present or Threatened Destruction, Modification, or Curtailment of Habitat or Range ............... 41
Roads............................................................................................................................................................................................................422

Mining, Pollutants, Other Habitat Degradation............................................................................................................................42

Overutilization for Commercial, Recreational, Scientific, or Educational Purposes Harvest in
Ocean and Recreational Fisheries ................................................................................................................. 42
Commercial Fisheries.............................................................................................................................................................................42
Recreational Fisheries............................................................................................................................................................................43

Disease or Predation ......................................................................................................................................... 45

Inadequacy of Existing Regulatory Mechanisms..............................................................................46
Federal.................................................................................................................................................................. 46
National Environmental Policy Act..................................................................................................................................................46
Endangered Species Act........................................................................................................................................................................47
National Forest Management Act......................................................................................................................................................47
Federal Clean Water Act.......................................................................................................................................................................48

State....................................................................................................................................................................... 48
State Fisheries Management:...............................................................................................................................................................48

Other Anthropogenic or Natural Factors...........................................................................................48
Artificial Propagation....................................................................................................................................... 48
Ocean Conditions............................................................................................................................................... 49
Climate Change.................................................................................................................................................. 49

Request for Critical Habitat Designation ...........................................................................................50
References ................................................................................................................................................51
Additional Figures:.................................................................................................................................62

Executive Summary
The Wild Fish Conservancy petitions to list one or more “evolutionary significant units”(“ESU(s)”) of Chinook salmon (Oncorhynchus tshawytscha) in the State of Alaska as athreatened or endangered species under the Endangered Species Act and to designate critical
habitat.
Chinook are anadromous, migrating from the ocean upstream to the freshwater streams of theirbirth to reproduce. Alaskan Chinook exhibit a predominately stream-type life-history, with theirjuveniles migrating to sea during their second year of life, normally within twelve to fifteen
months after emergence from spawning gravels. An important exception is the Situk River
Chinook population that exhibits an ocean-type life history, where juveniles migrate to sea
during their first year of life. Because Chinook spend more than half of their lives in the ocean,the National Marine Fisheries Service/ National Oceanic and Atmospheric Administration is the3responsible party to evaluate this petition and determine whether listing under the ESA is
warranted.
Alaskan stream-type (also commonly known as “spring”) Chinook generally spawn in July andAugust. Fry emerge from the spawning gravel the following late spring and rear in their natal
waters for a year (occasionally two years if water temperatures are exceptionally cold and/or
unproductive) before migrating to marine waters the following spring. Depending on theindividual population, marine rearing may predominately take place in nearshore waters,
offshore waters of southeast Alaska and the Gulf of Alaska, or further offshore in the North
Pacific. (See sections on individual populations below for details on marine rearing behaviors.)
Recent work on the genetics of ocean- and stream-type Chinook in the west coast south of theCanadian border have shown that the stream-type life-history is largely controlled by a few
regulatory genes that result in mature Chinook migrating to their natal rivers several months
prior to spawning. This behavior has been termed “premature migration”. In contrast, ocean-type(commonly referred to as “fall”) Chinook return to their natal rivers to spawn very near the timeof spawning (days or weeks) and thus do not exhibit premature migration behavior. It is not (yet)known if the spawning migration timing of Alaska stream-type Chinook is controlled bypremature migration regulatory genes as southern US stream-type Chinook. Regardless, there isevidence that these unique life histories are being rapidly lost, and further species decline will
follow the current loss of not only abundance, but spatial structure, productivity, and diversity.
Alaska stream-type Chinook have unique habitat requirements for migration, spawning, juvenile
rearing, and adult residence in the ocean. Suitable spawning habitat is in mainstem rivers andtributaries, and requires cold water, cool resting pools in which to hold, clean spawning gravels,and optimal dissolved oxygen levels, water velocities, and turbidity levels. Chinook access tospawning habitat is threatened by interception in fisheries, habitat disturbance from mining andlogging, and in some cases anthropogenic barriers to migration. During upstream migration,
adult Chinook are in a stressed condition due to their reliance on stored energy to complete theirjourney upstream, leaving them highly susceptible to additional environmental stressors. During
their ocean residence, adults need nutrient-rich, colder waters that are associated with highproductivity that results in sufficient rates of salmonid growth and survival.
Additional information on the life history of Alaska Chinook is provided in ADF&G’s 2013
Chinook salmon stock assessment and research plan (ADF&G 2013). We include excerpts fromthat document below:“Much of what is known about the general life history of Chinook salmon in Alaska has
been summarized by Healey (1991) and Morrow (1980) and is briefly summarized herewith extensions to their summaries as cited. With some rare exceptions, Chinook salmon
4

in Alaska exhibit the stream-type life history where adult runs occur during spring andsummer, spawning occurs during summer and fall, the majority of juveniles spend one
year in freshwater before smolting, and make extensive ocean migrations to feed andmature.”“Run timing of adults varies across the state, with migrations into freshwater beginning
as early as April or as late as July. Chinook salmon in large river systems such as the
Yukon River may have a protracted run timing due to wide variation in distances fishmust migrate to disparate spawning areas. In some instances there may be two runs of
Chinook salmon in a single drainage where, for example, earlier arriving fish spawn insmaller tributary habitats and later arriving fish spawn in larger mainstem habitats. The
Kenai and Kasilof rivers, in Southcentral Alaska support such multiple runs of Chinook
salmon.”“Spawning of Chinook salmon primarily occurs between July and September, withcapacity of spawning populations limited by factors related to watershed area (Parken etal. 2006). Unlike the protracted run timing typically seen in many salmon species, timingof spawning appears to be highly synchronized and compressed in most Chinook salmon
populations in Alaska. Chinook salmon can spawn in a wide variety of habitats in termsof water depths, substrate type, and current velocities, although they prefer areas of highsubgravel flow, specifically found at the heads of riffles and in pools below log jams. Thispreference for high subgravel flow limits available Chinook salmon spawning area inmost rivers of Alaska.”“Fecundity of female stream-type Chinook salmon varies by size and is also thought tovary by population along a latitudinal gradient. For example, fecundity of fish in the
Salcha River drainage ranged from 7,400 to 13,400 eggs per female depending on length(Skaugstad and McCracken 1991), which is somewhat higher fecundity than thatreported in the general literature for Chinook salmon populations further south (Healyand Heard 1984).
“As with other Pacific salmon, female Chinook salmon deposit eggs into redds dug into
the streambed. Within the redd, Chinook salmon ova are susceptible to drying as riverlevels drop in fall and winter, freezing during winter, and mechanical abrasion due tofloods during summer and fall. Time to hatching varies with stream temperature,generally taking 12 or more weeks in Alaska. Fry emerge from the gravel 2 to 3 weeks
after hatching”“After hatching and emergence, fry disperse from spawning areas to feed in mainstem ortributary habitats of large watersheds. Juvenile Chinook salmon favor areas of moderate
5current and instream cover for feeding during summer. Some populations exhibit
migrations from tributaries into mainstem areas for overwintering. Understanding ofoverwinter survival rates for juvenile Chinook salmon in freshwater is very limited. Most
juvenile Chinook salmon in Alaska overwinter in freshwater and emigrate as age-1 smolt
the following spring, although there are juveniles in some Southeast Alaska populations
that migrate seaward at age-0 prior to their first winter (e.g., Situk River, Thedinga et al.
1998). Seaward emigration of smolt generally occurs between May and July (King andBreakfield 2002), with smolt ranging in length from approximately 50-100 mm (Pahlke etal. 2010).”“Very little is known about habitats occupied by juvenile Chinook salmon as they firstenter nearshore marine waters of Alaska. As with other populations of stream-type
Chinook salmon, it is thought that juveniles in Alaska spend little time in their natal river
estuary and rapidly move into the coastal currents along the shoreline where very little
biological sampling has been done to date. It has been hypothesized that the first year atsea is a critical period of growth (during summer and fall) and survival (during winter)for juvenile Chinook salmon, a period that is modulated by climatic conditions (Beamish
and Mahnkin 2001).”“As juveniles grow and begin to feed predominately on fish, they migrate further offshore
into the shelf areas of the Gulf of Alaska and Bering Sea, where there is information on
their distribution from coded-wire tag (CWT) recoveries and genetic analysis of samples
from various research cruises and from bycatch in Federal groundfish fisheries. These
data indicate that most Chinook salmon originating in the Gulf of Alaska migrate northand west from their natal streams in Southeast and Southcentral Alaska along the Alaska
Current, with some populations migrating as far as the Bering Sea (Larson et al. 2012).
As an exception, some stocks in Southeast Alaska rear near shore and entirely within theconfines of Southeast Alaska. Juvenile Chinook salmon in the Gulf of Alaska represent acomplex and highly variable mix of Alaska populations primarily originating inSouthcentral and Southeast Alaska, interspersed among populations and hatcheryreleases originating in Canada and the Lower 48. It appears that western Alaska andBristol Bay populations of Chinook salmon do not make extensive migrations into thecentral or eastern Gulf of Alaska. Relative abundance of juvenile Chinook salmon in the
Bering Sea tends to be related to distance from their natal river, with western Alaska andBristol Bay populations making up the bulk of Alaska-origin fish in the Bering Sea,
followed by western and central Gulf of Alaska populations, and then Southeast Alaska,
Canadian, and Lower 48 populations.”“As Chinook salmon grow and mature, they are thought to make seasonal migrations in
the ocean to feed. For example, a conceptual model of Chinook salmon in the Bering Sea
6

from high seas tag recoveries and stable isotope analyses suggest seasonal migrations
onto the Bering Sea shelf during winter and out into the Bering Sea basin during summer(Myers et al. 2009). After typically spending three to six years feeding in marine waters
on a variety of fish, squid, and euphausids, Chinook salmon in Alaska return back tonatal systems to spawn. Maturation rate tends to be sex and population specific, withmales tending to mature earlier than females and northern populations in Alaska
maturing later than more southerly populations. Chinook salmon in Alaska return
primarily at an age of five or six years, but can range in age from three to eight years.”

Since at least return year 2007, all stream-type populations throughout Alaska and the ocean-type
Situk River population in southeast Alaska have experienced significant declines in productivity
and abundance compared to levels exhibited in the previous two or more decades (ADF&G
2013, SP13-01; Jones et al. 2020; Heinl et al. 2021). The declines are even greater whencompared to more historic levels (e.g., Cobb 1930). While freshwater spawning and juvenile
rearing habitats in most Alaska Chinook rivers are in relatively healthy or minimally-disturbed
condition, habitats in some rivers are sufficiently disturbed in at least some river reaches and/or
associated riparian and upland areas to compromise spawning or rearing success of Chinook(e.g., Jones et al. 2020 and specific cases below). The major causes of the region-wide declines
in Chinook productivity and abundance are predominately due to factors in the marine rearing
and migratory environment. Global warming and climate change along with massive releases ofhatchery pink and chum salmon from Japan, Russia, and Alaska adversely impact marine foodwebs (Cunningham et al 2018; Ruggerone and Irvine 2018; Springer et al 2014; Springer et al
2018; Cheung and Frolicher 2020; Heneghan et al. 2023, Jones 2023, Ruggerone et al. 2023).
However, as noted by Jones et al. 2020, adverse freshwater conditions, particularly those related
to climate change impacts, may interact with adverse marine conditions to further depress
Chinook population productivity.
Alaska Chinook face increasing threats from rising stream temperatures during spawning,incubation, and/or juvenile rearing; alteration in stream flow at critical times during spawning,incubation, and juvenile rearing caused by changing precipitation patterns due to climate change(e.g., Jones et al. 2020); fish management decisions are changing the food web and associatedproductivity in the marine environment, exacerbated by ecological interactions with large-scalereleases of hatchery pink and chum salmon in Alaska, Japan, and Russia (Cunningham et al.
2018; Ruggerone et al. 2018; Springer et al 2014; Springer et al. 2018; Hennighan et al. 2023).
Existing federal and state regulatory mechanisms have proven unable to protect and recover
Alaska Chinook and their habitats. Alaska Chinook have suffered from chronically low
abundance for much of the past two decades. In 2013, the Alaska Department of Fish and Game(ADF&G) recognized “Alaska-wide downturns in productivity and abundance of Chinook
7

salmon stocks” and created a scientific research team to evaluate the declines, identify key
knowledge gaps, and recommend research to address knowledge gaps in order to improve themanagement of Chinook stocks and fisheries (ADF&G Chinook Salmon Research Team. 2013,
henceforth “report”).
Following the 2013 report, beginning in 2017 and 2018, several Chinook populations were
designated by ADF&G as “stocks of management concern” and action plans were developed torespond to the declines in abundance and productivity. ADF&G defines a “stock of management
concern as a concern arising from a chronic inability, despite the use of specific management
measures, to maintain escapements for a salmon stock within the bounds of the SEG, BEG, orOEG (“sustainable”, “biological”, or “optimal escapement goals”, respectively), or otherspecified management objectives for the fishery; a management concern is not as severe as aconservation concern” (State of Alaska special species fish stocks of concern as of April 2022
(https://www.adfg.alaska.gov/index.cfm?adfg=specialstatus.akfishstocks).
A stock of conservation concern is defined as “a concern arising from a chronic inability, despite
the use of specific management measures, to maintain a stock above a sustained escapement
threshold (SET); a conservation concern is more severe than a Management concern (5 AAC
39.222(f)(6))”. As of April 2022, there are 14 Chinook stocks from the southern end of the
Aleutian Islands to the Alaska/British Columbia border listed as stocks of management concern.
For at least 7 of the 14 there are recent (2022) “action plans”.
Recent spawning escapement data for eleven of these stocks, plus the Alsek and Situk river
populations, are listed in Table 1. Figures from the most recent spawning escapement report by
Heinl et al. 2021 show recent spawning escapements of four of the stocks and the Situk and
Alsek stocks. Figures for the remaining 3 stocks in the three action plan reports include more
recent escapements as shown on ADF&G’s Chinook research project website,
https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main.
Table 1 shows that 10 Chinook stocks have failed to meet the lower bound of their ADF&Gdesignated spawner escapement goals in the majority of the past six years from 2014 to 2019 andthe remaining three have failed to meet their goals in a majority of years since 2012. The twolargest Transboundary rivers that have the two largest Chinook populations subject to harvest in
southeast Alaskan commercial and recreational fisheries (Stikine and Taku) have failed to meettheir escapement goals in all seven years from 2016 to 2020.
It is noteworthy that the 13 depleted stocks span a large range of spawning populations sizes,
ranging from the King Salmon River (BEG: 120 to 240)) to the Transboundary Taku River(BEG: 19000 to 36000). Thus, Chinook populations of all population sizes from the southernside of the Aleutian Islands (Chignik) to the Alaska/British Columbia border display similar
declines in spawner abundance and productivity.
8

Table 1. Escapement goals and escapements for the most recent years available for 12
representative southeast Alaska Chinook populations. Data from ADF&G sources. Red fillindicates spawning escapements below the escapement goal lower limit. ‘BEG’: biologicalescapement goal; ‘SEG’: sustainable escapement goal. Escapements for the Karluk River for2019 to 2021 estimated from Figure 10.
StreamChickamin River
Unuk River
Stikine River
Andrew Creek
King Salmon
River
Taku River
Chilkat River
Alsek River
Situk River
Chignik River
Karluk River
Alexander Cr
Theodore R.

BEG Esc. Goal
2,150–4,300
1,800–3,800
14,000–28,000
650–1,500
120–240

2014
3,097
1,691
24,374
1,261
68

2015
2,760
2,623
21,597
796
50

2016
964
1,463
10,554
402
149

2017
722
1,203
7,335
349
85

2018
2,052
1,971
8,603
482
30

2019
1,610
3,115
13,817
698
27

2020
2,280
1,135
9,753
470
100

2021
2,404
2,666
8,376
530
134

19,000–36,000
1,750–3,500
3,500–5,300
450–1,050
1,300 – 2,700
3,000 - 6,000
2,100 – 6,000(SEG)
500 – 1,700 (SEG)

23,532
1,529
3,357
475
2,816
1,182
911

23,567
2,452
5,697
174
1,945
2,777
1,117

9,177
1,380
2,514
329
1,743
3,434
754

8,214
1,173
1,741
1,187
1,037
2,600
170

7,271
873
4,348
420
725
3,155
296

11,558
2,028
6,319
623
1,417
~4000
NA

15,593
3,180
5,286
1,197
1,178
~2900
596

11,341
2,038
5,616
1,064
1,072
~2800
288

312

426

68

21

18

NA

111

38

FIGURESFIGURES (Figures numbers 2, 3, 5, and 7 – 9 from Heinl et al. 2021, Review of salmon
escapement goals in southeast Alaska, 2020. ADF&G FM 21-03; figures 1, 4, 6, and 10 from
ADF&G’s Chinook Research Project web page;https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main).

9

Figure 1. Unuk River Chinook Salmon escapements 1977 – 2022 from ADF&G’s Chinook
Research Project web page;https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main.
Accessed July 4, 2023.

10Figure 2.Estimated Chickamin River Chinook salmon escapements, 1975–2019, and biologicalescapement goal range of 2,150–4,300 large spawners.

11

Figure 3.Estimated Andrew Creek Chinook salmon escapements, 1975–2019, and biologicalescapement goal range of 650–1,500 large spawners.

12Figure 4. Stikine River Chinook Salmon escapements 1975 – 2022 from ADF&G’s Chinook
Research Project web page;https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main.
Accessed July 4, 2023.

13

Figure 5.Estimated King Salmon River Chinook salmon escapements, 1975–2019, and biologicalescapement goal range of 120–240 large spawners.

14

Figure 6. Taku River Chinook Salmon escapements 1975 – 2022 from ADF&G’s Chinook
Research Project web page;https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main. Accessed July 4, 2023.

15

Figure 7.Chilkat River Chinook salmon escapements (mark–recapture estimates), 1991–2019,and biological escapement goal range of 1,750–3,500 large spawners.

16

Figure 8.Estimated Alsek River Chinook salmon escapements, 1976–2019, and biologicalescapement goal range of 3,500–5,300 fish.

17

Figure 9.Situk River Chinook salmon escapements (weir counts), 1976–2019, and biologicalescapement goal range of 450–1,050 large spawners.
.

18

Figure 10. Karluk River spawning Chinook salmon from 1985 to 2022. From Chinook Salmon
Research Initiative;
https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative_karluk.historical.

The Three 2022 Actions Plan Reports
ADF&G issued three regional information reports for the stock status and action plans in 2022;
RIR IJ22-13 for the Unuk River and Chickamin Creek; RIR IJ 22-15 for the Transboundary
Stikine River and Andrews Creek, and RIR IJ 22-17 for the Transboundary Taku River, and theChilcat and King Salmon rivers. Each report repeated several of the research and monitoring
recommendations of the 2013 report, including, in particular, monitoring of the annual
abundance of outmigrating smolts. This is a critical monitoring variable as it enables estimationof the per-spawner smolt production which in turn enables the estimation of smolt recruit perspawner stock recruit models, as well as more robust estimation of smolt-to-adult return survivalin the marine environment. (see for example, the 2013 report. Pages 9 – 11).

19

As far as we can determine, this critical recommendation has not been addressed for any of the
Chinook populations designated as stocks of management concern and/or listed in the 2013
report. Currently, and at the time of the 2013 report, four rivers are monitored regularly toestimate smolt abundance indirectly by estimating adult recaptures of coded-wire tagged outmigrating smolts. Aside from questions about the accuracy and robustness of the derived smolt
abundance from this approach, due to the multiple ages at maturity of Alaska Chinook thismethod requires several years of returning adult abundance estimates for any given brood year
and associated year of smolt outmigration. So, yearly estimates of smolts-per-spawner (or per
female spawner) are not possible. Further, the lack of annual estimates of total smolt abundance
severely inhibits annual pre-season estimates of adult returns and also reduces the ability todetect annual changes in smolts-per-spawner. These shortcomings all inhibit the ability to
manage large-scale fisheries and potential spawning escapements in the science-based
precautionary manner that is warranted considering the data (e.g., Table 1 and figures above).

Notice of Petition

Petitioners Wild Fish Conservancy are petitioning to list Alaskan Chinook salmon(Oncorhynchus tshawytscha) as a threatened or endangered species and to designate critical
habitat under the Endangered Species Act. The petitioners file this petition pursuant to § 553(e)of the Administrative Procedure Act (“APA), 5 U.S.C. §§ 551-559 and § 1533(b)(3) of theEndangered Species Act, and 50 C.F.R. part 424.14, which grant interested parties the right topetition for issuance of a ruling that ESA listing is warranted.
With this document we are requesting that NOAA-NMFS initiate a status review of Chinook insouthern Alaska, which encompasses all Chinook populations that enter the marine environmentof the Gulf of Alaska (GOA). This includes all populations on the southern side of the Aleutian
Peninsula, Cook Inlet, and the coast of Alaska south of Cook Inlet to the southern end of the
Alaska/British Columbia border.
A status review is warranted based on recent information concerning the productivity andescapement of numerous Chinook populations, including both stream-type and ocean-type
Chinook. Climate change is having detrimental effects on streamflow and water temperature in
freshwater and the marine rearing and migration environments. Habitat degradation is occurring
through human activities, including logging and mining, and industrial fisheries take Chinook
both directly and indirectly through commercial troll, net and trawl fisheries, and in recreationaland subsistence fisheries. A lack of fundamental information and monitoring of Chinook smolt
and parr abundance, changes in the marine food web due to massive releases of hatchery pink
and chum salmon in southeast Alaska and the northwestern Pacific (Japan and Russia) that affect20

the invertebrate and forage fish populations on which Chinook forage, and a continuing lack ofsufficient monitoring information and regulatory mechanisms to ensure effective conservation ofthese populations, all put these populations at risk of extinction. We summarize the available
information below.
Contact information for petitioners:

Wild Fish Conservancy
P.O. Box 402
Duvall, WA 98019
info@wildfishconservancy.org

Legal BackgroundDefinition of Evolutionary Significant Unit

The Endangered Species Act (ESA) defines "species" to include "any subspecies of fish or
wildlife or plants, and any distinct population segment of any species of vertebrate fish or
wildlife which interbreeds when mature." 16 USC§ 1533(16), see also California State Grange v.
National Marine Fish, 620 F.Supp 2d 1111, 1121 (ED Cal 2008). The ESA does not define theterm "distinct population segment." Grange at 1121.
In 1991, the National Marine Fisheries Service ("NMFS") promulgated its "Policy on Applying
the Definition of Species Under the Endangered Species Act to Pacific Salmon" or"Evolutionarily Significant Unit ("ESU Policy." (56 Fed.Reg.58612 (Nov. 20, 1991)). The ESU
Policy provides that a population (or particular collection of populations) of Pacific salmonids is
considered to be an ESU, and therefore considered for listing under the ESA, if it meets thefollowing two criteria: (1) The population must be substantially reproductively isolated fromother nonspecific population units; and (2) The population must represent an importantcomponent in the evolutionary legacy of the species. Isolation does not have to be absolute, but it
must be strong enough to permit evolutionarily important differences to accrue and to be
evolutionarily maintained in different population units. The second criterion is met if the
population contributes substantially to the ecological and/or genetic diversity of the species as awhole (Waples 1991). Grange at 1123-24. That is, the loss of the population(s) would constitutea material diminishment of the ecological, life-history or genetic diversity of the species as awhole.
21

NMFS putatively considers all available lines of evidence in applying those criteria, including
specifically data from DNA or genomic analyses (" ... data from protein electrophoresis or DNA
analysis can be very useful because they reflect levels of gene flow that have occurred overevolutionary time scales."), ESU Policy, 56 Fed. Reg. at 58518; see also Definition of "Species"
Under the Endangered Species Act: Application for Pacific Salmon, NOAA Tech Memo NMFS
F/NWC-194 (Waples 1991) at p.8 ("The existence of substantial electrophoretic or DNA
differences from other conspecific populations would strongly suggest that evolutionarily
important, adaptive differences also exist."). The ESU Policy is an interpretation by NMFS ofwhat constitutes an ESA-listable "distinct population segment" (DPS), and is a "permissible
agency construction of the ESA." Grange at 1124, citing Alsea Valley Alliance v. Evans, 161 F.
Supp 2d 1154, 1161 (D.Or. 2001).

Listing an ESU as an Endangered or Threatened
When considering whether a species or subspecies, including an ESU, is endangered or
threatened, NMFS must consider:i.

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

ii. Overutilization for commercial, recreational, scientific, or educational purposes;iii. Disease or predation;
iv. The inadequacy of existing regulatory mechanisms; orv.

Other natural or manmade factors affecting its continued existence.

16 U.S.C. § 1533(a)(l). The species shall be listed where the best available data indicatesthat the species is endangered or threatened because of any one, or a combination of, those
five factors. 50 CFR § 424.11 (c).

Best Available Science Supports listing of at least one Alaskan ESU of Chinook Salmon

Southern Alaska Chinook constitute one or more Distinct ESUs

Since no Alaska Chinook populations have previously been petitioned for listing under the ESA,
Alaskan Chinook population structure has not been characterized in terms of ESUs. Designationof Chinook ESUs is therefore a first step in the development of a status review on the basis of22which the merits of listing one or more ESUs under the ESA can be evaluated. Basic life-history
and differences in the spatial structure of Alaska’s numerous Chinook populations suggests that
populations in southern Alaska are likely to form one or more ESUs distinct from Bering Sea
populations from Bristol Bay, Yukon, Kuskokwim, and Norton Sound.

Ecology and Biology of Southern Alaska Chinook Description
Adult Chinook salmon are the largest of all Pacific salmon, typically measuring 36 inches inlength and often exceeding 30 pounds at maturity; many adults exceed 40 pounds. Chinook
salmon vary in size and age of maturation, with smaller size related to longer distance migration,
earlier timing of river entry, and cessation of feeding prior to spawning. As length corresponds toage, two year-old adults tend to be around 40 centimeters long, and six year-old adults often
measure one meter in length (Healey 1991).
Chinook salmon have a different appearance depending on location and lifecycle. In the ocean,
the Chinook salmon are a robust, deep-bodied fish with bluish-green coloration on the backwhich fades to a silvery color on the sides and white on the belly. Adult Chinook have black
irregular spotting on the back and dorsal fins and on both lobes of the caudal or tail fin. Adults
are distinguished from other sympatric salmonid species by the spotting on the caudal fin and theblack coloration of their lower jaw (Moyle et al. 2008). When Chinook spawn, their physicalappearance changes; colors of spawning Chinook in freshwater range from red to copper to deepgray, depending on the location and degree of maturation. Males typically have more redcoloration than females, which are typically gray. Older adult males (4-7 years) are distinguishedby their "ridgeback" condition and by their hooked nose or upper jaw. Females are distinguishedby a torpedo-shaped body, robust mid-section, and blunt noses.
Juvenile Chinook in fresh water are camouflaged by silver flanks with parr marks (darker
vertical bars or spots) which are bisected by the lateral line. Chinook fry are 30-45 mm andfingerlings are 50-120 mm in fork length (Healey 1991). When juvenile Chinook go throughsmoltification to prepare physiologically for life in the ocean, they change to a more silvery color
and their scales and tails lengthen (Healey 1991). Smolts have bright silver sides and their parrmarks recede to mostly above the lateral line.

Distribution
Southern Alaska Chinook salmon inhabit coastal river basins in Alaska, from the southern end of
the Aleutian Islands south to the Alaska/British Columbia border.

23

Life Cycle and Physiology
Chinook salmon are anadromous, migrating from the ocean upstream to the freshwater streamsof their birth; and semelparous, dying after one spawning episode. Chinook salmon grow throughsix basic life history stages: eggs, alevins, fry, parr, smolts, and adults. Eggs are laid in stream
gravels in spawning beds, or redds. Alevins are yolk sac larvae that hatch from the eggs andremain buried in spawning gravels until the yolk sac is absorbed. Fry are free swimming postlarvae young that emerge from spawning gravels and begin feeding in the stream or migrate from
it. Parr are young salmon adapted to freshwater. Smolts are young salmon that have undergone
the physiological, biochemical, morphological and behavioral changes, called smoltification, thatallow them to live in salt water in the ocean. Chinook salmon reach adulthood in the ocean,
typically attaining maturity at the age of 4 - 6 years, then migrating into freshwater to repeat thecycle. For stream-type Chinook having one year of freshwater growth after emerging from thespawning gravel (yearlings), Chinook that mature at ages 4 to 6 experience 3 to 5 years of marine
growth, respectively, when age is calculated from emergence from the spawning gravel, insteadof from summer/fall egg deposition. Ocean-type Chinook, having only weeks to one or twomonths of freshwater growth (subyearlings) that mature at ages 4 to 6 experience 4 to 6 years ofmarine growth, respectively.
Within this general life history Chinook display a broad array of tactics that include: variation inage at seaward migration; variation in length of freshwater, estuarine, and oceanic residence;variation in ocean distribution and ocean migratory patterns; and variation in age and season of
spawning migration, and variation in sex-specific age-at-maturity. Differences in Chinook
salmon life history are best explained by the timing of their spawning migration (i.e., spring-run,summer-run, fall-run, late fall-run or winter-run), the length of their juvenile residence infreshwater (i.e., subyearling or yearling or older smolt migration), the sizes and ages of mature
adults, and the sex ratio of returning adults. These differences result in a variety of smoltificationand maturation strategies.
Adult early migrating Chinook typically enter southern Alaskan streams from March throughJune (ADF&G 2013). Chinook adults require deep holding pools proximate to spawning areas,
where they hold for a week or more prior to spawning; this holding period occurs during thesummer. Spawning of Alaska Chinook can occur as early as mid-July, but primarily runs from
August to September (ADF&G 2013).
Chinook require about 258 square feet or more of well oxygenated gravel per spawning pair(Burner 1951). Female Chinook defend their redd after spawning is begun. Early in the spawningperiod they can stay on the redds for about two weeks, while their residence late in the season is
only 4-5 days. Spawning adults can be chased off redds easily by minor disturbances, which ifthey occur frequently enough can result in death of the adult prior to successful spawning. Eggs
24

are laid in depressions excavated on the bottom of streams in shallow river reaches. Chinook
eggs are the largest of all Pacific salmon species with a small surface-to-volume ratio, making
them more sensitive to reduced oxygen levels than other Pacific salmon.
Several months after egg deposition, in the late spring, juvenile Alaska Chinook emerge from thegravel. Adequate water flows through the spawning gravels is essential for egg and alevinsurvival. Stream conditions, particularly those affecting subgravel flows, can have a dramaticeffect on the survival of eggs to hatching and emergence. Any increases in siltation in spawning
beds can cause high mortality (Healey 1991). At the time of emergence, fry generally swim or
are displaced downstream, although some fry are able to maintain their residence at the spawning
site.
Downstream migration of smolts peaks between May and July, depending on stream temperature(Roper 1995). Juveniles rear in estuaries or lower river mainstems, using deep riffles, woody
debris and shoreline riparian vegetation for cover and feeding areas (Kostow 1995). Ocean-type
Chinook salmon tend to utilize estuaries and coastal areas more extensively for juvenile rearing(Myers et al. 1998). Perhaps the most significant process in the juvenile life history of Chinook
salmon is smoltification, or the physiological, morphological, and behavioral changes associatedwith the transition from freshwater to marine existence.
Alaska Chinook mature and return to natal streams primarily after 3 to 5 (or more) years ofrearing in the marine environment at ages of 4 to 6 years, although occasional jack males
returning at 3 years of age (after 2 years of marine rearing) are not uncommon.

Importance of age structure for Alaska Chinook
The age structure of adult Chinook is critically important to the productivity and resilience ofChinook salmon populations. This is especially the case for females. For females, fecundity isstrongly positively correlated with size (body length and weight), which in turn is strongly
positively correlated with age. Older females are generally larger and more fecund than younger
females. In addition, older females generally have larger eggs that are better provisioned withenergy resources, giving emergent fry and parr higher survival than those from smaller eggs ofyounger females. (Healy 1991; Quinn 2005). In addition, older, larger-bodied females are theonly spawners capable of spawning in deep, fast water habitats with large substrates; thus, loss ofthese spawners is a direct loss of population capacity and productivity. With climate change,these life history strategies are important to the resilience, life-history and genetic diversity, andrebuilding potential of Alaska Chinook.

25

The body size and age-at return of Alaska Chinook have been declining across most populations
for more than two decades (Lewis et al. 2015). Data from the Taku River from Richards andWilliams (2018) provide particularly concerning data. The size of age 6 females has declined
dramatically since 2008. Up to 2008, age-6 females had a mean mideye-to-fork (MEF) length of
850 millimeters (mm). From 2009 to 2016, the average MEF declined to 800 mm. Similar but
weaker trends were observed for age 4 and 5 female spawners (Richards and Williams 2018,slides 22 and 23). Exacerbating the significant declines in mean body length of age 6 females is astrong decline in the proportion of the spawning population composed of age 6 females. During
the period from 1988 to 2011: from 30% to 55% up until the late 1990s to 20% and less in the
mid-2000s (Richards and Williams 2018, slide 23).
The declines in the size and age of females spawners in the Taku is likely to be similar for many,
if not most, of Alaska’s Chinook population, including those that have been identified by
ADF&G as stocks of management concern.
These declines indicate that during the past two decades or more there has been a continuing
decline in the total egg deposition represented by large females. This implies that spawner
escapement goals related to maximum sustainable yield (MSY) or other management targets
determined in the recent past are not achieving target egg deposition. This further implies thatescapement goals need to be increased in order to achieve the requisite expected total egg
deposition that may achieve management total adult return targets. To achieve recovery under
the ESA, it is likely that spawner escapement goals may need to be further increased above
estimated MSY levels (see, e.g., Lichatowich and Gayeski 2020).
Habitat Requirements
Because of the variety and large array of habitats Chinook salmon utilize, they require a numberof particular conditions in order to survive and reproduce. Chinook salmon habitat use andrequirements are best studied for their time spent in freshwater, although estuarine and ocean
conditions are also significant to survival and viability. Human activities can significantly
degrade freshwater and estuarine habitat suitability.

Migration and Spawning Habitat
During upstream migration, adult Chinook are in a stressed condition due to their reliance on
stored energy to complete their journey upstream, leaving them highly susceptible to additional
environmental stressors. Although adult upstream migration distances for Southern Alaska

26

Chinook are relatively short compared to some salmon migrations in larger river systems,
migration can still require considerable effort.
Chinook salmon require access to spawning habitat in mainstem rivers and tributaries, cold
water, cool pools in which to hold, clean spawning gravel, and particular dissolved oxygen
levels, water velocities, and turbidity levels in order to successfully migrate and spawn. Accessto spawning habitat is threatened by migration barriers, dams, and water diversions. Variability
in water flows can prevent Chinook salmon access to certain streams for spawning. During
migration and spawning, low water temperatures are crucial to the success of Chinook salmon.
According to McCullough (1999), adults are more sensitive to higher temperatures thanjuveniles, as higher temperatures can increase the adults’ metabolic rate and deplete their energy
reserves, weaken their immune system, increase exposure to diseases, and slow or prevent
migration. Water temperatures at or above 15.6ºC can increase the risk of onset and severity of
diseases (Allen and Hassler 1986). Healthy and intact riparian vegetation is critical, as it provides
much needed root strength to stabilize stream margins and floodplains, and shade to keep watercool (Moyle 2002) and help create “thermal refugia” in which migrating Chinook salmon canescape high temperatures (Berman and Quinn 1996; Torgerson et al. 1999; Gonia et al. 2006).
The presence of cold water is threatened by dams, water withdrawals, and channel alterations, aswell as logging and mining which decreases riparian vegetation and alters groundwater
dynamics.
Spawning occurs primarily in low gradient habitats with large cobbles loosely embedded ingravel and with sufficient flows for subsurface infiltration to provide oxygen for developing
embryos (Healy 1991; Moyle et al. 2008). Optimal spawning temperatures for Chinook salmon
are less than 13°C (McCullough 1999). Migrating adults also need dissolved oxygen levels
above five mg/l, deep water (deeper than 24 cm), breaks from high water velocity, and water
turbidity below 4,000 ppm (NRC 2004). Spawning gravel also must be free of excessive
sediment such that water flow can bring dissolved oxygen to the eggs and newly hatched fish.
With too much sediment, incubating eggs are smothered and reproductive success rate declines
significantly. Logging, mining, and other human activities can increase inputs of fine sediment in
Chinook spawning habitat and significantly reduce fry emergence rates and embryo survival.

Juvenile Rearing Habitat
During rearing and juvenile out-migration, Chinook require certain temperatures, habitat
diversity, and water quality characteristics. After hatching, juvenile Chinook require rearing
habitat before making their migration to the estuary and onto the ocean. Ideal fry rearing
temperature is estimated at 13ºC and temperatures above 17ºC are linked with increased stress,27

predation, and disease. High water temperatures can prevent smoltification, an essential processthat prepares fish to leave freshwater habitat (McCullough 1999).
During juvenile rearing and downstream dispersal, Chinook are vulnerable to low flow and hightemperature conditions, which can prevent them from reaching their destinations andsignificantly increase mortality during migration (Moyle et al. 1995; Trihey and Associates
1996). Stream temperature during out-migration is critical, as prolonged exposure totemperatures of 22-24ºC has resulted in high mortality for migrating smolts, and juveniles whotransform into smolts above 18ºC may have low survival odds at sea (Baker et al. 1995; Myrick
and Cech 2001). Hence, where and when necessary, juvenile Chinook salmon also seek out andexploit localized cool water refugia that offer relief from warm ambient water temperatures insummer (Sauter et al. 2001; Belchik 2003; Ebersole et al. 2003; Sutton et al. 2007)
Riparian vegetation provides relief for juvenile Chinook from high temperatures, as well as
shelter from predators (Moyle 2002). Logging, mining (and associated toxic contamination ofwaters), fossil fuel development, and other extractive industries can all reduce streamsidevegetation and negatively affect the quality of juvenile rearing habitats. Habitat diversity isimportant for juvenile Chinook survival, as juveniles face predation by fish and invertebrates, aswell as competition for rearing habitat from other salmonids, including hatchery Chinook(Healey 1991; Kelsey et al. 2002). Chinook require the correct grades of gravel, the right depths
and prevalence of deep pools, the existence of large woody debris, and the right incidence ofriffles (Montgomery et al. 1999). This allows for a variety of habitats which are required by
Chinook at different life stages.
Chinook fry may compete for shallow water rearing habitat with hatchery fish. Increased riverflows mitigate this competition and help Chinook survival by increasing habitat on the river’s
edge, where fry (under 50 mm) feed and hide from predators (NRC 2004).
As juvenile Chinook migrate down river, they prefer boulder and rubble substrate, water velocity
slower than 30 cms-1 (Healey 1991). These conditions allow juveniles to use the faster-moving
water in the center of the river for drift feeding, while resting in the slower areas (Trihey and
Associates 1996). Smaller fish tend to stay in the slower-moving water near the banks of theriver. Logging can increase turbidity, and climate trends increase the frequency and size of flood
peaks scouring redds and/or prematurely displacing fry and young parr.
Juvenile Chinook require high levels of dissolved oxygen (DO). Low DO levels decrease alevinand fry survival; decrease successful Chinook egg incubation rates; decrease the growth rate forsurviving alevins, embryos, and fry; force alevins and juveniles to move to areas with higher
DO; and negatively impact the swimming ability of juvenile Chinook (NCWQCB 2010). If DO

28

levels average lower than 3-3.3 mg/L, 50% mortality of juvenile salmonids is likely, while inwater above 20°C, daily minimum DO levels of 2.6 mg/L are required to avoid 50% mortality.
Once juvenile Chinook reach the estuary, smolts prefer near shore areas near the mouth of theriver (Healey 1991). Juveniles change location with the tide as the salinity of the water changes.

Ocean Habitat
Once Chinook enter the ocean, most reside at depths of 40-80 meters (Healey 1991). Some
research suggests that unlike most stream- and ocean-type Chinook further south, Alaska
Chinook may exhibit either relatively local, within or near to state marine waters whether
stream- or ocean-type or migrate further offshore including regions outside of Southeast Alaska.
In the marine environment, Chinook salmon require nutrient-rich, cold waters associated withhigh productivity and higher rates of salmonid survival. Warm ocean regimes are characterized
by lower ocean productivity which can affect salmon by limiting the availability of nutrientsregulating the food supply and increasing the competition for food. Climate and atmosphericcirculation conditions can affect these conditions (NMFS 1998c). In order to survive in themarine environment, Chinook salmon also require favorable predator distribution andabundance. This can be affected by a variety of factors including large scale weather patterns
such as El Niño and more generally, marine heatwaves (e.g., Cheung and Frolicher 2020, Jones
2023). NMFS (1998c) cites several studies which indicate associations between salmon survival
during the first few months at sea and factors such as sea surface temperature and salinity.
The role of changing ocean conditions in influencing survival of south Alaska coast Chinook andother salmon is considerable. However, predictive understanding of marine survival of wild
Alaska Chinook salmon is elusive, in part due to fluctuating ocean conditions, but also because
few data are collected on marine survival of wild populations.
Sharma and Liermann (2010) concluded that change in sea surface temperature anomalies
reflected in the El Niño phenomenon in recent decades have produced ocean conditions
increasingly hostile to Chinook salmon. Kilduff et al. (2015) reported that survival rates ofChinook and coho salmon released from hatcheries along the Pacific coast of North America
have shifted coherence from the Pacific Decadal Oscillation (Mantua et al. 1997) to ageographically different sea surface anomaly, the North Pacific Gyre Oscillation. Inter-annual El
Niño events are still seen as the proximal event influencing ocean survival, but the expression of
El Niños in relation to North Pacific circulation has apparently changed since the 1980s. Thesechanges also are reflected in the status of other marine species (Kilduff et al. 2015). Changing
ocean currents are also reflected in the changing behavior and influence of large-scaleatmospheric circulation, which further influences marine food web productivity through29

advection and ocean deposition of continental dust that changes nutrient dynamics in the North
Pacific Gyre (Letelier et al. 2019). Increasingly synchronous marine survival among numerous
widely distributed salmon stocks suggests that more volatile Pacific-coast-wide fluctuations insalmon abundance are occurring (Kilduff et al. 2015).
The lack of marine survival and growth data for most wild stocks, including Alaskan Chinook,precludes a fuller understanding of the role their diverse life histories play in conferring
resilience to fluctuations in ocean conditions. We do know as a rule that diversity of life history
in salmon populations affords a critical buffer against such large-scale environmental variation(Schindler et al. 2010; Moore et al. 2010; Carlson and Satterthwaite 2011; Satterthwaite andCarlson 2015; Brennan et al. 2019).

Diet
Chinook salmon diet varies depending on growth stage. As alevins, young Chinook rely on
nutrients provided by the yolk sack attached to the body until leaving the redd after a few weeks.
After emerging from the gravel, young Chinook fry begin to feed independently. Juveniles feedin streambeds before gaining strength to make the journey to the ocean. During this time, fry
feed on terrestrial and aquatic insects and amphipods. As juveniles migrate toward the ocean,they may spend months in estuarine environments feeding on plankton, small fish, insects, ormollusks. Small fry feed primarily on zooplankton and invertebrates, while larger smolts feed on
insects and other small fish (i.e. chironomid larvae, chum salmon fry and juvenile herring;
Healey 1991). At sea, where the bulk of feeding and growth is done, adult Chinook typicallyfeed on small marine fish, crustaceans, and mollusks (i.e., squid). Adult Chinook grow quickly inthe estuary and gain body mass during their time at sea, building fat reserves that are required for
upstream migration and spawning. During the upstream migration and holding in fresh water,
adult Chinook do not feed or properly digest food, and thus they rely on stored energy.

Natural Mortality
Alaska Chinook salmon, like other salmon are preyed upon by a wide variety of predators infreshwater and saltwater. However, their presence in freshwater as large-bodied adults during
relatively low streamflow conditions makes them especially vulnerable to inland predators. Other
natural mortality factors about which little is known include disease, and natural catastrophes
such as large natural landslides, earthquakes, forest fires and volcanic eruptions.

30

Taxonomy
Chinook salmon (Oncorhynchus tshawytscha) are in the genus Oncorhynchus (order
Salmoniformes, family Salmonidae), which contains all Pacific salmon.

Population Structure and Significance of Life History Variation
Stream-type populations represent a major contribution to life history variation in Chinook
salmon at the species level, but also at the level of river-specific stocks. Life history variation
within species, and both among and within populations, is now widely recognized as a criticalfactor in determining salmon viability, productivity, and resilience in the face of environmental
fluctuations. Diversity of life history in salmon populations affords a critical buffer against bothlarge-scale and local environmental variation (Schindler et al. 2010; Brennan et al. 2019). The
loss of life history diversity in Chinook salmon, whether by decline or extirpation of local
populations, or by demographic dominance of hatchery-reared fish, leads to increasing
synchronicity of population fluctuations, hence reduced resilience and productivity, andincreasing risk of local extinctions (Moore et al. 2010; Carlson and Satterthwaite 2011;
Satterthwaite and Carlson 2015).
Chinook with different life histories also face different conditions in the marine environment, sothey may be affected much differently by effects of changes in marine currents and temperatures,food web conditions and predation. Moore et al. (2004) identified early and late adult return
timing as one of several life history variations that contributed to dampening fluctuations in
population abundances and biomass via portfolio effects in steelhead populations in British
Columbia. This observation constitutes a specific example of the “portfolio effect” of withinbasin diversity that confers stability, spreads risk of stresses and threats, and sustains the
productive capacity of salmon populations (Brennan et al. 2019). A critically importantcomponent of the within-population portfolio effect is the presence of multiple ages at maturity,
which enhances the resilience of a population to environmental variation in marine conditions byspreading the risk of any year’s cohort encountering particularly adverse marine rearing andmigratory conditions.
The role of adult salmon carcasses in spawning areas in transferring important marine nutrients
to often nutrient-limited freshwater and inland riparian ecosystems is today well-recognized(Cederholm et al. 1999; Gresh et al. 2000; Zabel and Williams 2002; Peery et al. 2003;
Scheuerell et al. 2005; Schindler et al. 2010). The increased spatial and temporal dispersion of
Chinook salmon furthered by the presence of spring-run ecotypes, particularly in wild
populations, supports this natural ecosystem enrichment function. An integral part of this nutrient
31

transfer is the role that spawning and post-spawning spring- and summer-run Chinook play inproviding a reliable natural food resource for other animals: guilds of predators and scavengers,
including many birds, mammals, fishes, and invertebrates (Cederholm et al. 1999; Minikawa et
al. 2002; Peery et al. 2003; Schindler et al. 2010; Field and Reynolds 2013). Some northeast
Pacific orcas are strongly selective foragers on Chinook salmon (Ford and Elli 2006), such thatthe contribution of Chinook salmon to overall stability and abundance of the species at sea could
play a significant role in orca health and survival.

32

Status
Historical baseline
John Cobb, in his summary of Pacific fisheries published in 1930 reports total catch by species ineach pacific state in the year 1918. In that year, an estimated 16,010,746 pounds of Chinook
salmon were landed, based on an assumed average of 22 pounds per-Chinook (Cobb 1930).
Seines, gill nets, pound nets, and hook and line were all gears used to capture the 727,761
Chinook recorded. This important historical baseline regarding the average size of Chinook
landed has been shifted towards considerably smaller sizes (weights) in the last several decades,
as documented for Alaska Chinook by several recent publications (Lewis et al. 2015, Ohleberger
et al. 2018, Oke et al. 2020). The below table summarizes cannery pack of king salmon in Alaska
from 1898 to 1919.
PACK OF CANNED SALMON IN ALASKA
FROM 1898 TO 1919, BY SPECIES (COBB
1930)
YEAR King, or spring.
Cases
Value
1898
12,862…..
1899
23,400…..
1900
37,715…..
1901
43,069…..
1902
59,104…..
1903
47,609…..
1904
41,956…..
1905
42,125$141,999.00
1906
30,834$116,222.00
1907
43,424$181,718.00
1908
23,792$99,867.00
1909
48,034$207,624.00
1910
40,221$214,802.00
1911
45,518$295,088.00
1912
43,317$243,331.00
1913
34,370$139,053.00
1914
48,039$241,105.00
1915
88,251$408,226.00
1916
65,873$353,420.00
1917
61,951$644,447.00
1918
49,226$485,295.00
1919
151,733$1,820,796.00
33

Basin Summaries of Population Status and Threats

Southern Aleutian Island Watersheds

Chignik RiverAs shown in Table 1, the Chignik population has a BEG (biological escapement goal) range of1300 to 2700 large (MEF >660 mm Fork length (FL). The lower bound of this goal has been
missed in 2 of the 6 years from 2014 to 2019. The Chignik Chinook population was listed as astock of management concern in 2023 (ADF&G 2023).
Cook Inlet Populations
Jones et al. 2020 provide a detailed examination of spawner escapement and productivity (log
recruits-per-spawner) for data for 15 Cook Inlet Chinook populations up to 2015. These aregraphically summarized in Jones et al. 2020, figures S1 and S4. Here, we provide escapement
data for two of these populations up to 2018, from the most recent ADF&G cook Inlet
escapement analysis, McKinley et al. 2020.
Alexander Creek
Alexander Creek was listed as a stock of management concern in 2010 (ADF&G 2023). It has arecommended SEG of 1900-3700. McKinley et al 2020. Fishery Manuscript no. 20-02, page 12.
Recent escapements, 2016 to 2018: 754, 170, 296, respectively (McKinley et al 2020, Appendix
table A1).
Theodore River
The Theodore River was listed as a stock of management concern in 2010 (ADF&G 2023). It has
an SEG of 500 to 1700. Recent escapements (incomplete counts), 2016 to 2018: 68, 21, 18,
respectively. (McKinley et al 2020, Table 1). From 2007 to 2015, escapements have all been
below the lower bound of the SEG, ranging from a low of 179 in 2012 to a high of 486 in 2007.
In only 3 of these years (2007, 2013 and 2015) have escapements been greater than 400.
(McKinley et al 2020 Appendix table A-21.
Populations whose status is reported in the three 2022 stock status and action plan reviews:

34

Unuk River
Unuk River was listed as a stock of management concern in 2017 (ADF&G 2023). It is locatednear Ketchikan and produces the largest run of Chinook salmon in southern southeast Alaska. It
is one of four Chinook stocks “for which a full stock assessment program is conducted annually.
Full stock assessment programs include coded-wire-tagging of juveniles, which, in combination
with adult monitoring and sampling programs, provides estimates of smolt abundance, parr tosmolt overwinter survival rates, marine survival rates (smolt-adult), total annual run size
(escapement plus harvest by age), and total return, along with estimates of harvest (calendar
year) and exploitation (brood year) rates (Meridith et al. 2022, page 2).
Chinook from this population rear predominately in the inside marine waters of southeast
Alaska. Some also rear in the Gulf of Alaska and Bering Sea (ibid, Figure 2, page 23). As shownin Table 1 the lower bound of the BEG has not been attained in the four of the years between
2014 to 2019. Unuk Chinook are harvested in SEAK commercial and sports fisheries. Most of
the troll harvest occurs in the spring season and averaged 15% between 2011 to 1917, and 4% in2018 and 2019. Recently during this period, the winter troll fishery season has closed on March
15 “…to reduce harvest on early run Chinook salmon in all SEAK systems” (ibid. page 8).
Harvest rates in commercial drift net and purse seine fisheries (combined), which occur closer tocoastal and terminal marine areas, averaged 11.1% from 2010 to 2017, 12.1% in 2018-19 (ibid,
page 3). Thus, the harvest rate in these commercial fisheries appears to have increased during or
following the implementation of the action plan in 2018.
Sports harvest occurs primarily from May through July. Since 2014, when restrictive measures inthe terminal areas near Ketchikan were implemented, most harvest has occurred in June. Harvest
rates averaged 8% “over the past 10 years and 5% over the most recent 5 years” (ibid. page 3).
Many of the non-troll commercial and sports fisheries in marine areas have included periods
when Chinook non-retention regulations were implemented, thus requiring the release of allincidentally caught Chinook. However, in all three of these recent stock status and action plan
reviews, no mention is given of Fisheries Related Incidental Mortality (FRIM), and hence noestimates provided numbers or rates of incidental Chinook mortality in any fishery when nonretention measures are in effect. Incidental mortality would be expected from multiple fisheries
including, but not limited to, the Gulf of Alaska groundfish trawl fishery.
Despite these recent measures directed at reducing harvest rates on Chinook, the lower bound of
Unuk escapement goals has not been met in 7 of the 11 years from 2012 to 2022 (Figure 3, page
11 above).

35

Chickamin River
The Chickamin River was listed as a stock of management concern in 2021. It is located near
Ketchikan in south southeast Alaska and produces the second largest run in the region. Similar to
the nearby Unuk River, Chinook from this population rear predominately in inside waters ofsoutheast Alaska. Some also rear in the Gulf of Alaska and Bering Sea (Meridith et al. 2022,
page 3). The Chickamin Chinook population has a BEG of 2150 to 4300 large females. As
shown in Table 1 and Appendix Figure A4 above, the Chickamin has failed to achieve the lower
bound of the BEG in the last 4 of the 6 years 2014-2019, despite similar recent reductions incommercial and sports harvest as the Unuk River population.
McKinley et al. 2022 (page 23) note that the “Chickamin River stock is part of the coastwide
Chinook salmon genetic baseline (Shedd et al. 2021); however, identifying wild ChickaminRiver Chinook salmon is convoluted because these fish are used as brood stock for hatcheryreleases in SEAK. In addition, Chickamin River Chinook salmon cannot be distinguished fromother SEAK wild stocks at this time”. Such confounding of the genetic identifiability of Chinook
populations in the south-southeast region due to the source of local wild populations as hatcherybroodstock significantly compounds the ability of managers to identify harvest impacts ofsoutheast Alaska fisheries on population of management/conservation concern.

Stikine River
The Stikine was listed as a stock of management concern in 2021. It is a transboundary river. All
Chinook spawning habitat is in Canada. It is an outside rearing stock. Stikine Chinook aremanaged through the provisions of the Pacific Salmon Treaty. Like the Unuk River, the Stikine
is one of four “SEAK Chinook salmon stocks for which a full stock assessment program isconducted annually (Salamone et al. 2022, page 3).” Stikine Chinook “are harvested throughout
SEAK in commercial and sport fisheries during their spawning migration in late winter andspring (March to June), though most of the fish enter SEAK waters through Chatham andSumner Straits…” (ibid. page 3). Commercial troll harvest thus occurs primarily during thespring period may 1 to June 30). Harvest also occurs in marine sport and “in federally managed
subsistence fisheries in the freshwaters of the U.S. portion of the Stikine River. In addition,
Stikine River Chinook salmon are harvested in Canadian in-river commercial, recreational(sport), and First Nation food (subsistence) fisheries” (ibid.). There are no directed subsistence
fisheries for Chinook in these waters; Chinook are harvested (and retained) as incidental(bycatch) in subsistence fisheries primarily directed a sockeye salmon. No information or data
are provided by Saloamone et al. (2022) on FRIM in any fisheries that directly or indirectly
encounter Stikine Chinook.
36

As with the other populations with action plans reviewed in 2022, the Stickine has failed toachieve the lower bound of its BEG in the majority of the most recent years for which
escapement data is available. In the case of the Stikine, the lower bound of the BEG has not been
met the past 7 years 2016 – 2022 (Table 1. Figure X (page 17 above). Salamone et al. (2022)
state that since 1996 “Stikine River Chinook salmon escapements averaged 24,450 large fish;
however, the recent 10-average escapement of 15,000 fish and recent 5-year average escapementof 10,000 fish are substantially lower than the long-term average, and escapements have been
below the BEG range for 5 consecutive years since 2016 (Table 1)” (page 3).
It is noteworthy that although (1) the recent 10-year average escapement was only marginallygreater than the lower bound of the BEG of 14000, (2) the decline in productivity of Stikine
Chinook was recognized in the 2013 report, and (3) escapements dropped significantly below thelower bound beginning in 2016 Stikine Chinook were not listed as a stock of management
concern until 2020.
Andrew Creek
Andrew Creek was listed as a stock of management concern in 2021. It is a Clearwater tributary
to the lower Stikine, located entirely in Alaska. Andrew Creek Chinook are an inside rearing
population that is “genetically and behaviorally distinct from Stikine River Chinook salmon”(Salamone et al. 2022, page 4). Andrew Creek Chinook “is a significant source of Chinook
salmon broodstock in SEAK hatcheries” and therefore “genetic stock identification methods
cannot be used to distinguish wild Andrew Creek Chinook salmon from hatchery Chinook
salmon produced from Andrew Creek broodstock” (ibid., page 5).
The Andrews Creek Chinook population has not met the lower bound of its BEG in the last 4 of
6 years from 2014 to 2019 (Table 1; Figure X., page 15 above). Recent reductions in commercial
and marine sport fisheries in response to declining escapements beginning around 2015 havefailed to improve escapements. Recent fisheries management actions include Chinook nonretention regulations for fisheries not directed at Chinook, including subsistence and personal use
fisheries (Salamone et al. 2022, page 14-15). In addition, as noted previously for other southeast
Alaska Chinook populations, there is no discussion of FRIM nor any FRIM data.

Chilcat River
The Chilcat River was listed as a stock of management concern in 2017. It “is a glacial systemthat empties into Chilkat Inlet in northern Lynn Canal, near Haines … that supports the fifth37largest stock of Chinook salmon in SEAK. Chilkat River Chinook salmon predominantly rear in
the inside waters of SEAK…..” and “is 1 of 4 stocks for which a full stock assessment isperformed annually by the department.” (Hagerman et al. 2022, page 2.) The Chignik has a BEG
of 1750 to 3500.
The Chlicat has failed to achieve the lower bound of its BEG 4 of the 6 years from 2014 to 2019
(Table 1), and 6 of the past 8 years from 2012 to 2019 (Appendix Figure A9). The Chinook stock
was designated a stock of management concern in 2018.
Chilcat Chinook are harvested directly in southeast Alaska commercial mixed-stock troll(primarily during the spring troll season) and drift gill net fisheries, and in mixed stock marine
sports fisheries and a small terminal marine sports fishery in Chilcat Inlet. Chilcat Chinook arealso harvested incidentally in sockeye salmon subsistence fisheries in Chilcat Inlet and theChilcat River. Harvest rates on Chilcat Chinook averaged 26% between 2005 and 2015. Harvest
restrictions implemented in response to the recent failures to meet the BEG and the 2018
designation have resulted in an average harvest rate of 9% in 2018 to 2020 (ibid., page 3).
Despite the recent harvest reductions, the Chilcat has failed to attain the lower bound of the BEG
in most years since 2016. As is the case for most southeast Alaska Chinook populations, marine
commercial and sports fisheries directed at Chinook, as well as commercial and sports fisheries
targeting other species such as sockeye, encounter immature Chinook (ibid., page 12).
Unfortunately, no estimates of the proportion or numbers of immature Chinook encountered or
harvested in southeast Alaska marine fisheries appear to have been made or reported. There has
been no reported data for FRIM in fisheries that encounter or harvest Chilcat Chinook.
King Salmon River.
“The King Salmon River was listed as a stock of management concern in 2017. It is a clearwater
system located about 30 km (19 mi) south of Juneau on Admiralty Island. This river has the only
documented island stock of Chinook salmon in southeast Alaska...” (Hagerman et al. 2022, page4). The Chinook stock is an inside rearing stock. It is the smallest Chinook population among
those regularly monitored for spawning escapements (Table 1). “This stock does not support
directed fisheries but presumably is harvested incidentally in SEAK marine waters in sport andcommercial fisheries. Harvest estimates of the King Salmon River Chinook salmon are notavailable because the stock contribution in marine fisheries has not been determined.” Harvest
rates on a nearby hatchery population is used as a surrogate and ADF&G estimates that “since2011 harvest rates on these Chinook salmon have averaged 46%” (ibid.).
The King Salmon River Chinook population was designated as a stock of management concern
in 2017. Management measures directed to reducing harvest impacts in nearby marine38

commercial and sport fisheries have not improved spawning escapements to the river. Spawningescapements have failed to achieve the lower bound of the BEG (120 large females) in 5 of the 6
years from 2014 to 2019 (Table 1).

Taku River.
“The Taku River was listed as a stock of management concern in 2021. It is a transboundary
glacial system that supports an outside rearing stock of Chinook salmon. The Taku Riveroriginates in British Columbia and drains over 17,000 square kilometers before its terminus at
Taku Inlet, approximately 40 km northeast of Juneau. The Taku River Chinook salmon run
spawns entirely in Canada and is managed through provisions of Chapter 1 of the PST”
(Hagerman et al. 2022, pages 4-5). This is the largest of all southern Alaska Chinook
populations. The lower bound of the BEG is 19000 large Chinook.
Most Chinook are harvested in southeast Alaska marine waters, both directly in commercial troll
and net fisheries and indirectly in marine sport fisheries, in-river personal use and subsistence
fisheries, and in-river Canadian commercial sockeye fisheries. The majority of harvest impacts
occur in Alaskan marine waters.
“Since 1989, escapements averaged 36,400 large fish; however, the recent 10-year average
escapement of 15,330 fish and the recent 5-year average of 10,360 fish are substantially lowerand have been below the escapement goal range for 5 consecutive years (Hageramn et al. 2022,
page 5”). The lower bound of the escapement goal has not been attained in the most recent 6year period for which data is available (2016 to 2021, Figure X). Of even greater concern, in the
5 most recent years for which data is reported by Hagerman et al. 2022 (2016 to 2020, Table 4,
page 33), the total run (harvest plus escapement) was below the lower bound of the BEG,
showing that even if there were no harvest of Taku Chinook, the lower bound could not be
attained!

Situk River
The Situk River is a clearwater system located near Yakutat, Alaska, that supports an outsiderearing stock of Chinook salmon. Situk Chinook are the most important population of ocean-type
population in Alaska, which are generally rare in the state. Situk-origin Chinook salmon are
harvested primarily in directed sport, commercial, and subsistence fisheries located in river, in
the Situk-Ahrnklin Inlet, and in nearby surf waters. It has a Biological escapement goal (BEG)39

of 450 to 1050 large Chinook. In recent years there have been total closures of Chinook fishing
and/or in-season restrictions of in-river subsistence fisheries.
As shown in Table 1 and Figure 9 between 2014 and 2018, the Situk failed to meet the lower
bound of the BEG in 3 of the 5 years. Although the lower bound of the goal was met in 2019 andthe upper bound exceeded in 2020 and 2021, there have been conservation closures of Chinook
fisheries both before and after 2021.
Alsek River
The Alsek River is a transboundary glacial system that originates in southwestern Yukon andnorthwestern British Columbia and flows into the Gulf of Alaska approximately 80 km southeastof Yakutat. This river supports an outside-rearing stock of Chinook salmon (Heinl et al., Review
of salmon escapement goals in southeast Alaska, 2021. ADF&G FM 21-03). It has a BEG of
3500 – 5300 Chinook, including age-2 spawners, unlike the majority of other Alaska Chinook
populations. The Alsek River stock, like other Chinook salmon stocks in Alaska, has recently
experienced a decline in productivity. (ibid). As shown in Table 1 and Figure 9, the Alsek failed
to meet the lower bound of the BEG in 3 of the 5 years between 2014 and 2018. The goal was
met in 2020 and exceeded the upper bound in 2019 and 2021.
Karluk River
The Karluk Chinook stock was listed as a stock of management concern in 2010 (ADF&G
2023). We are unaware of any action plan for the Karluk.
The Karluk River is located on the southwest end of Kodiak Island and supports 1 of only 2
native stocks of Chinook salmon on the Kodiak Archipelago. From its source at the outlet of
Karluk Lake, the Karluk River flows 22 miles to its terminus at Karluk Lagoon. Freshwater entryof Chinook salmon occurs during late May through mid-July with 50% of the run typically overby mid-June. All subsistence and commercial inshore harvests are directly reported and sport
harvest is estimated by a survey. Karluk River Chinook salmon are harvested incidentally to
directed sockeye, pink, chum, and coho salmon commercial fisheries within the Westward
Region (ADF&G Chinook Salmon research Initiative web pagehttps://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative_karluk.main).
The Karluk has a BEG of 3000 to 6000 large spawners. As shown in Table 1 and Figure 9, theKarluk failed to meet the lower bound of the escapement goal in 5 of the 9 years from 2013 to2021.
Summary of stock status
40

The 13 Chinook salmon populations, including the 7 populations with action plans developed in
response to their recent designation as stocks of management concern, span the full spatial range
from the southern side of the Aleutian Islands and Cook Inlet to the Alaska/British Columbia
border, and spawn across a range of recent population (run) sizes from less than 100 to several
tens of thousands (approximately two plus orders of magnitude). All have failed to attain thelower bounds of their current ADF&G spawner escapement goals. These failures reflect the
decline in productivity of the majority of Alaska wild Chinook populations since about 2007(2013 report; Jones et al. 2020), reflective of declines in either or both freshwater and marine
survival of various life stages.
We next address the primary threats and limiting factors that are likely drivers or contributors tothese declines.
Threats to the Species
Current threats can be characterized into 5 main categories: (1) Present or threatened destruction,
modification, or curtailment of its habitat or range; (2) Overutilization for commercial,recreational, scientific, or educational purposes; (3) Disease or predation (4) Inadequacy of
existing regulatory mechanisms and (5) Other natural or anthropogenic factors affecting its
continued existence. Among the most significant of other manmade factors, and a subject ofintense public debate is the overutilization for commercial and or recreational/sport fisheries.

Present or Threatened Destruction, Modification, or Curtailment of Habitat or Range
Logging
Clear-cut logging and deforestation can lead to erosion and sedimentation in streams and rivers.
Excess sediment can smother salmon eggs and suffocate developing fry. Clear-cut logging andthe construction of logging roads increases natural erosion and sedimentation in streams, andexacerbates the risk of landslides. When forests are removed, the soil becomes exposed andvulnerable to erosion, especially during heavy rains. Logging also causes habitat loss by theremoval of riparian vegetation, which serves as critical habitat for salmon. Trees and streamside
shrubs provide shade, habitat for salmon prey, and help maintain optimal water temperatures forsalmon. The removal of these forests can expose streams to direct sunlight, leading to elevatedwater temperatures. Chinook are sensitive to stream temperature changes, and excessively warm
water can stress or even kill them. Elevated stream temperatures can also affect the timing of
salmon migrations and spawning.

41

Other factors, such as habitat fragmentation through undersized road crossings, increased peakstreamflow, and chemical runoff resulting from pesticide and herbicide use can also negatively
impact Chinook Salmon.
Roads
Building roads for logging, mining, or other purposes can alter stream and river channels,
increase sedimentation, and block salmon migration routes. Culverts and bridges can also impede
fish passage if not designed to accommodate salmon.
Mining, Pollutants, Other Habitat Degradation
Active mines, exploratory mines, and derelict mining operations can release pollutants into water
bodies, impacting water quality and salmon habitat. Contaminants such as heavy metals can betoxic to Chinook salmon. These impacts are often underestimated by resource managers andmining companies often fall short of their own water quality goals (Sergeant et al. 2022).
Mining operations in the transboundary region are also out of the jurisdiction of the UnitedStates, which puts downstream salmon populations within US waters at risk.
Overutilization for Commercial, Recreational, Scientific, or Educational Purposes Harvest in
Ocean and Recreational Fisheries
Commercial Fisheries
Overharvest of Alaskan Chinook salmon in commercial fisheries has been a concern in various
regions of Alaska at different times. Overharvest occurs when more Chinook salmon are caught
than sustainable, leading to declines in populations and potential long-term negative
consequences. In many cases, Chinook salmon are caught in mixed-stock fisheries, wheremultiple salmon species and stocks are harvested together. This can make it challenging to target
specific Chinook salmon populations and prevent overharvest of vulnerable stocks. This dynamic
can also be exacerbated by the bycatch, or the capture of non-target species in commercial
fishing gear. Bycatch of Chinook salmon at different life-cycle stages, such as sub-adult Chinook
bycatch from the pollock fishery, is often unaccounted for in total harvest estimates.
In 2022, only 39% of escapement goals were met for Chinook salmon, despite commercial
Chinook harvest increasing slightly for 2022. The 5 year- average of escapement goal
achievement is only 51%. (Munro, 2023). This figure is alarming since 17 Chinook salmon
stocks are listed as stocks of concern within Alaska.

42

Figure 1. Combined Chinook Salmon Sport and Commercial Catch, South Central Alaska. Catch includes fish kept
and fish released from salt and freshwater, Bristol Bay drainages excluded (Nushagak, Wood River, Togiak, andKvichak Rivers in sport fisheries and all direct fisheries in South Central and Southeast Alaska Commercial Chinook
Fisheries). Graph excludes commercial bycatch of Chinook in groundfish fisheries.

Recreational Fisheries
Recreational fisheries have also experienced substantial declines throughout the state of Alaska,
from a high of approximately 200,000 fish in 2005 and 2006 to less than a 100,000 fish in 2021,
the most recent data that is publicly available from the Alaska Department of Fish and Game.

43

Figure 2. Chinook Salmon Catch, South Central Alaska. Catch includes fish kept and fish released fromsalt and freshwater, Bristol Bay drainages excluded (Nushagak, Wood River, Togiak, and Kvichak
Rivers).
Alaska Sport Fishing Survey database [Internet]. 1996–. Anchorage, AK: Alaska Department of Fish andGame, Division of Sport Fish (cited October 4, 2023). Available from:http://www.adfg.alaska.gov/sf/sportfishingsurvey/

44

Figure 3. Chinook (King) Salmon Sport Catch, Southeast Alaska. Catch includes fish kept and fish released from salt
and freshwater. Alaska Sport Fishing Survey database [Internet]. 1996–. Anchorage, AK: Alaska Department of Fish
and Game, Division of Sport Fish (cited October 4, 2023). Available from:http://www.adfg.alaska.gov/sf/sportfishingsurvey/

Disease or Predation
Diseases within Alaska include Furunculosis (Aeromonas salmonicida), Piscine Reovirus (PRV),
Cold Water Disease (Flavobacterium psychrophilum), Trichodinids, bacterial kidney disease(Renibacterium salmoninarum), bacterial gill and kidney disease, among many others. Throughregular monitoring conducted by state and federal agencies, we know that disease is a constant45

problem when artificially rearing fish in high densities (Saunders 1991) and cross-species
infection may be occurring through the large releases of Pink and Chum salmon near to Chinook
salmon populations. Rearing facilities expose captive fish to increased risk of carrying pathogens
because of the increased stresses associated with simplified and crowded environments. It is
probable that fish transferred between facilities, adult fish carcasses being outplanted into thewatershed, and other fish released from hatcheries, have acted as disease vectors to wild fish andother aquatic organisms. These diseases, amplified within the fish hatchery environment,
contribute to the mortality of fish at all life stages and can travel rapidly to areas well beyond
where effluent pipes are discharged. The out planting of juvenile and adult fish can transfer
disease upstream of the rearing site, and there is the potential for lateral infection through thetravel of avian, mammalian, and other terrestrial predators which overlap with the distribution of
artificially propagated fish. These dynamics contribute to disease driven mortality at all life
stages in wild Chinook populations.
Predation on Chinook Salmon in Alaska has been estimated to be near or below harvest levels,
however, increases in marine mammal populations, including northern resident killer whales,
consume significant numbers of Chinook (Chasco et. al., 2017). While most research has
focused on modeling predation on adult salmon, assumptions within these models leadconfidence intervals surrounding these estimates to be large. Other portions of the life cycle also
have documented predation events, including Humpback whales targeting hatchery releases ofjuvenile Chinook salmon from hatcheries in Southeast Alaska (Chenoweth et al. 2017).
Inadequacy of Existing Regulatory Mechanisms
FederalNational Environmental Policy Act
The National Environmental Policy Act (NEPA) (42 U.S.C.4321-4370a) requires federal
agencies, including the U.S. Forest Service and U.S. Bureau of Land Management, to consider
the effects of management actions on the environment. The NEPA process requires theseagencies to describe a proposed action, consider alternatives, identify and disclose potential
environmental impacts of each alternative, and involve the public in the decision-making
process. However, a NEPA analysis does not prohibit these agencies from choosing project
alternatives that may adversely affect Alaskan Chinook salmon or their habitats. As a result, theNEPA process often results in the disclosure of impacts but affords little to no protections. The
agencies must analyze the impacts of their actions on the species, but are not required to selectalternatives that avoid harm to Chinook. Federal land management agencies regularly plan
timber sales, maintain and utilize roads, and conduct other actions that harm Chinook. Chinook46

salmon are not formally listed as a sensitive species by either the Forest Service or the Bureau ofLand Management (USWFS and USBLM 2018), impacts to these salmon from agency
management actions get less scrutiny under NEPA.
Endangered Species Act
Alaskan Chinook salmon are not currently protected under the federal Endangered Species Act.
The Act offers potential protections through Habitat Conservation Plans (HCP) which cover nonlisted species. Several Habitat Conservation Plans exist in Alaska under the U.S. Endangered
Species Act that may provide benefits to Alaskan Chinook salmon. A few examples of theseinclude:-Tongass Land Management Plan HCP-

Alaska Department of Transportation and Public Facilities HCP-

Kensington Gold Mine HCP

Another potential Endangered Species Act protection could be through co-occurrence with otherlisted species. As of 2021, Stellar Sea Lion (western population), Northern Sea Otter (Southwest
Alaska Population), Spectacled Eider, Steller’s Eider, North Pacific Humpback Whale, North
Pacific Right Whale, and Cook Inlet Beluga Whales are species found in the State of Alaska
which are listed as threatened or endangered.
While Chinook could benefit somewhat from protection of these species and indirect benefits to
Chinook habitat may occur, none of these listings appear to have slowed the decline of Chinook
salmon in Alaska. Existing state and federal programs and regulations have failed to prevent
continued high rates of habitat loss, and many threats to Chinook continue unabated.
National Forest Management Act
Under the National Forest Management Act, the Forest Service is required to “maintain viable
populations of existing native and desired nonnative vertebrate species” (36 C.F.R. §219.19). As
with NEPA, this requirement does not prohibit the Forest Service from carrying out management
actions and projects that harm species or their habitat, but merely states that “where appropriate,measures to mitigate adverse effects shall be prescribed” (36 C.F.R.§219.19(a)(1)). This clausedoes little to limit long term impacts to salmonid habitat in Alaskan coastal watersheds fromagency management actions such as logging, road-building, mining and other activities.

47

Federal Clean Water Act
The Clean Water Act (CWA) establishes the basic structure for regulating the discharge ofpollutants into U.S. waters and for regulating quality standards of U.S. surface waters. Under the
CWA, the U.S. Environmental Protection Agency) implements pollution control programs andsets wastewater standards for industry and water quality standards for all contaminants in surface
waters. The CWA also provides federal funding to restore habitat, clean up toxic pollutants andreduce run-off.
Under Section 404 of the CWA, discharge of pollutants into waters of the U.S. is prohibited
absent a permit from the U.S. Army Corps of Engineers. Theoretically, the CWA should provide
some protection for stream and estuarine habitats used by Chinook. However, implementation of
the CWA, and the Section 404 program in particular, has fallen far short of Congress’s intent toprotect water quality (e.g., see Morriss et al. 2001).

State
State Fisheries Management:
5 AAC 39.222 is a regulation in Alaska that pertains to the policy for the management ofsustainable salmon fisheries. It provides guidelines and principles for managing salmon stocks
to ensure their long-term viability while trying to also support commercial, subsistence, sport,
and personal use fisheries. Despite the establishment of escapement goals, you can see from theabove information that corrective action has not been taken by the state of Alaska to adequately
protect Chinook salmon in the region of concern.
Other Anthropogenic or Natural Factors
Artificial Propagation
All hatchery operations within Alaska are for the intended purpose of augmenting commercial
and/or recreational fisheries, and are not designed for conservation or reintroduction purposes.
According to the North Pacific Anadromous Fish Commission, 12 hatcheries contribute tojuvenile release of approximately 9.45 million juvenile Chinook in southeast and southcentral
Alaska populations.
Artificial propagation of other species is also impacting Chinook Salmon. Competition with pinksalmon in the Pacific Ocean is a growing concern. As stated in the 2020 Hatchery Scientific48

Review Group 2020 technical document (HSRG, 2020), density dependence is a concern mostcommonly attributed to the spawner to smolt stage in the freshwater environment. However,considerable attention is also being paid to competition for prey availability in the ocean
environment. The negative consequences of competition on growth and survival have been
documented between declining salmon populations and highly abundant species such as pinksalmon in the ocean (Ruggerone and Irvine 2018, Ruggerone 2023). The substantial increase inpink salmon abundance over the last four decades is hypothesized to have negatively impacted
other species, and is being investigated as a leading cause of the collapse of the 2020 ocean
salmon harvests across the North Pacific Ocean. Decreases in Chinook prey, namely forage fish,
are correlated with increasing pink salmon abundance and these density-dependent interactions
were identified as key drivers of chinook productivity in the ocean ecosystem. Hatchery releasedata are compiled annually by the North Pacific Anadromous Fish Commission, are attachedherein, and should be evaluated for their impact on both Alaskan Chinook and the prey resources
they depend on in the marine environment. Assumptions that freshwater productivity is limiting
population productivity need to be weighed against the known collapse of their prey resources in
the marine environment.
Ocean Conditions

Ocean conditions in the Pacific Northwest exhibit patterns of recurring, decadal-scale variability(including the Pacific Decadal Oscillation and the El Niño Southern Oscillation), andcorrelations exist between these oceanic changes and salmon abundance in the Pacific Northwest(Stout et al. 2011). It is also generally accepted that for at least 2 decades, beginning about 1977,
marine productivity conditions were unfavorable for the majority of salmon and steelhead
populations in the Pacific Northwest, but this pattern broke in 1998, after which marine
productivity has been quite variable (Stout et al. 2011). NMFS (2011) was concerned about how
prolonged periods of poor marine survival caused by unfavorable ocean conditions may affectthe population viability parameters of abundance, productivity, spatial structure, and diversity.
Although Chinook salmon have persisted through many favorable-unfavorable ocean/climate
cycles in the past, much of their freshwater habitat was in good condition, buffering the effects ofocean/climate variability on population abundance and productivity. It is uncertain how these
populations will fare now that the synchrony between ocean cycles is starting to break down, andclimate change shifts large scale prey resources dependent upon the offshore environment.
Climate Change

Throughout the life cycle of Alaskan salmonids, there are numerous potential effects of climatechange (Stout et al. 2011; Wainwright and Weitkamp, in review). The main predicted effects in49

terrestrial and freshwater habitats include warmer, drier summers, reduced snowpack, higher
summer stream temperatures, and increased floods, which would affect salmonids by reducing
available summer rearing habitat, increasing potential scour and egg loss in spawning habitat,
increasing thermal stress, and increasing predation risk (NMFS 2011). In estuarine habitats, themain physical effects are predicted to be rising sea level and increasing water temperatures,
which would lead to a reduction in intertidal wetland habitats, increasing thermal stress,
increasing predation risk, and unpredictable changes in biological community composition(NMFS 2011). In marine habitats, there are a number of physical changes that would likely
affect salmonids, including higher water temperature, intensified upwelling, delayed springtransition, intensified stratification, and increasing acidity in coastal waters (NMFS 2011). Of
these, only intensified upwelling would be expected to benefit coastal-rearing salmon; all theother effects would likely be negative (NMFS 2011).
Projected changes in regional climatic and weather patterns due to global climate change will
have negative effects on Alaskan coastal aquatic ecosystems and salmonids. Long-term warming
trends and increasing weather variability in the Pacific Northwest will result in more frequent
events (e.g., droughts, intense precipitation, and periods of unusually warm weather) that wereconsidered extreme during the twentieth century, and the magnitude of these events may also
exceed recent historical levels (Reiman and Isaaks 2010).

Request for Critical Habitat Designation
The Petitioners request the designation of critical habitat for Alaskan Chinook concurrent withlisting. Critical habitat should encompass all known and potential freshwater spawning andrearing areas, migratory routes, estuarine habitats, riparian habitats and buffers, and essential
near-shore ocean habitats and important marine nursery areas.

50References

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Additional Figures:
Spawner escapement figures updated thru 2022 from ADF&G
https://www.adfg.alaska.gov/index.cfm?adfg=chinookinitiative.main. Accessed July 4, 2023.

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Taku River spawning Chinook salmon from 1973 to 2022

63

Spawning escapements of early-run Kenai River Chinook salmon, 1986 to 2019. Escapements
and goals through 2016 are germane to all fish and thereafter are based on large fish

64

Spawning escapements of late-run Kenai River Chinook salmon, 1986 to 2019. Escapements andgoals through 2016 are germane to all fish and thereafter are based on large fish65

Stikine River spawning Chinook salmon from 1975 to 2022

66

Unuk River spawning Chinook salmon from 1977 to 2022

67