Biological Report 82(11.116) 

December 1989 

Species Profiles: Life Histories and 

Environmental Requirements of Coastal Fishes 

and Invertebrates (Pacific Northwest) 

SOCKEYE SALMON 

NATIONAL WETLANDS 

RESEARCH CENTER LIBRARY 

780 Cffjunderne Blvd. 

' Fish and Wildlife Service 

Coastal Ecology Group 

Waterwavs Ex~eriment Station 

U.S. Department of the Interior U.S. Army Corps of Engineers 
Biological Report 82 (1 1.116) 

TR EL-82-4 

December 1989 

Species Profiles: Life Histories and Environmental Requirements of Coastal 

Fishes and Invertebrates (Pacific Northwest) 

SOCKEYE SALMON 

Gilbert B. Pauley, Ron Risher, and Gary L. Thomas 

Washington Cooperative Fishery Research Unit 

School of Fisheries 

{Jniversity of Washington 

Seattle, WA 98195 

Project Officer 

David Moran 

U.S. Fish and Wildlife Service 

National Wetlands Research Center 

1010 Gause Boulevard 

Slidell. LA 70458 

Performed for 

Coastal Ecology Group 

Waterways Experiment Station 

U.S. Army Corps of Engineers 

Vicksburg, MS 39 180 

U.S. Department of the Interior 

Fish and Wildlife Service 

Research and Development 

National Wetlands Research Center 

Washington, DC 20240 
This series may be referenced as follows: 

U.S. Fish and Wildlife Service. 1983-19-. Species profiles: life histories and environmental requirements of 

coastal fishes and invertebrates. U.S. Fish Wildl. Serv. Biol. Rep. 82(11). U.S. Army Corps of Engineers, TR 

EL-82-4. 

This profile may be cited as follows: 

Pauley, G.B., R. Risher, and G.L. Thomas. 1989. Species profiles: life histories and environmental requirements of 

coastal fishes and invertebrates (Pacific Northwest)--sockeye salmon. U.S. Fish Wildl. Serv. Biol. Rep. 

82(11.116). U.S. Army Corps of Engineers, TR EL-82-4. 22 pp. 
NATIONAL WETLANDS 

PREFACE 

RESEARCH CENTER LIBRARY 

700 Cajundome Blvd. 

la fayehe, LA. 70506-3 7 52 

This species profile is one of a series on coastal aquatic organisms, principally fish, of sport, commercial, or ecological 

importance. The profiles are designed to provide coastal managers, engineers, and biologists with a brief comprehensive 

sketch of the biological characteristics and environmental requirements of the species and to describe how populations 

of the species may be expected to react to environmental changes caused by coastal development. Each profile has 

sections on taxonomy, life history, ecological role, environmentalrequirements, and economic importance, if applicable. 

A three-ring binder is used for this series so that new profiles can be added as they are prepared. This project is jointly 

planned and financed by the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service. 

Suggestions or questions regarding this report should be directed to one of the following addresses. 

Information Transfer Specialist 

U.S. Fish and Wildlife Service 

National Wetlands Research Center 

NASA-Slidell Computer Complex 

1010 Gause Boulevard 

Slidell, LA 70458 

U.S. Army Engineer Waterways Experiment Station 

Attention: WESER-C 

Post Office Box 63 1 

Vicksburg, MS 39180 
CONVERSION TABLE 

Metric to U.S. Customary 

Multiply 

millimeters (mm) 

centimeters (cm) 

meters (m) 

meters 

kilometers (km) 

kilometers 

square meters (m3 

square kilometers (km2) 

hectares (ha) 

liters (L) 

cubic meters (m3) 

cubic meters 

milligrams (mg) 

grams (g) kilograms (kg) 

metric tons (t) 

metric tons 

kilocalories (kcal) 

Celsius degrees (" C) 

inches 

inches 

feet (ft) 

fathoms 

statute miles (mi) 

nautical miles (nmi) 

square feet (ft2) 

square miles (mi2) 

acres 

gallons (gal)3 

cubic feet (ft ) 

acre-feet 

ounces (oz) 

ounces 

pounds (lb) 

pounds 

short tons (ton) 

British thermal units (Btu) 

Fahrenheit degrees (" F) 

3.968 

1.8 (" C) + 32 

U.S. Customary to Metric 

25.40 

2.54 

0.3048 

1.829 

1.609 

1.852 

0.0929 

2.590 

0.4047 

3.785 

0.0283 1 

1233.0 

28350.0 

28.35 

0.4536 

0.00045 

0.9072 

0.2520 

0.5556 (" F - 32) 

To Obtain 

inches 

inches 

feet 

fathoms 

statute miles 

nautical miles 

square feet 

square miles 

acres 

gallons 

cubic feet 

acre-feet 

ounces 

ounces 

pounds 

pounds 

short tons 

British thermal units 

Fahrenheit degrees 

millimeters 

centimeters 

meters 

meters 

kilometers 

kilometers 

square meters 

square kilometers 

hectares 

liters 

cubic meters 

cubic meters 

milligrams 

grams 

kilograms 

metric tons 

metric tons 

kilocalories 

Celsius degrees 
CONTENTS 

... PREFACE ............................................................................... 111 

CONVERSIONTABLE ................................................................. iv 

FIGURES ................................................................................ vi 

ACKNOWLEDGMENTS .................................................................. vii 

NOMENCLATLTRE/TAXONOMY/RANGE .................................................... 1 

MORPHOLOGY/IDENTIFICATION AIDS ..................................................... 1 

REASON FOR INCLUSION IN SERIES ....................................................... 4 

LIFE HISTORY ........................................................................... 4 

Spawning .............................................................................. 4 

EggsandFecundity ....................................................................... 4 

AlevinsandFry .......................................................................... 5 

LakeResidence .......................................................................... 6 

SaltwaterLile ........................................................................... 6 

GROWTHCHARACTERISTICS ............................................................. 7 

THEFISHERY ............................................................................ 8 

ForecastingModels ....................................................................... 8 

1 PugetSoundStocks ....................................................................... 8 

Columbia River Stocks .................................................................... 12 

North Coastal Stocks ...................................................................... 13 

ECOLOGICALROLE ...................................................................... 13 

ENVIRONMENTALREQUIREMENTS ....................................................... 14 

Temperature ............................................................................. 14 

Salinity ................................................................................. 15 

DissolvedOxygen ........................................................................ 15 

Substrate .............................................................................. 15 

WaterDepth ............................................................................. 15 

WaterMovement ......................................................................... 15 

Turbidity ............................................................................... 16 

Oilspills ............................................................................... 16 

REFERENCES .......................................................................... 17 
FIGURES 

Number lzas 

1 Sockeye salmon ..................................................................... 1 

2 Major rivers and lakes supporting sockeye salmon in the Pacific Northwest ..................... 2 

3 Major sockeye salmon rearing lakes in the Fraser River, Rivers Inlet, and Smith Inlet 

systems of British Columbia ........................................................... 3 

4 Estimated commercial catch of sockeye salmon in Asia, North America, and the Japanese 

mothership fishery ................................................................... 9 

5 Average annual commercial catch of sockeye salmon in important coastal and high seas 

fishing areas ........................................................................ 9 

6 Commercial catches of blueback salmon in the Columbia River ............................... 12 
ACKNOWLEDGMENTS 

I am grateful to Richard Thorne and Donald Rogers, University of Washington, for their reviews of the manuscript. 
.............................. : .............................................. .. 

Qncorhynchzrs nerka ( Walbaum 1792) 

Figure 1. Sockeye salmon (after Hart 1973). 

SOCKEYE SALMON 

Scientific name .............. Oncorhynchus nerka (Walbaum) 

Preferred common name .......................... Sockeye salmon 

(Figure 1) 

Other common names ..................... Blueback, red salmon, 

kokanee (Lacustrine stocks only) 

Class ............................................................... Osteichthyes 

Order ........................................................... Salmoniformes 

Family .............................................................. Salmonidae 

Geographic range: Found from the Klamath River, 

California, to the Yukon River, Alaska, but 

commercially important only from the Columbia River 

to Bristol Bay. The major Alaskan spawning grounds 

are in tributaries and lakes of the Kenai, Chignik, 

Naknek, Kuichak, Wood, and Kodiak Island river 

systems. In the Pacific Northwest, the major spawning 

river for sockeye is the Fraser River system in British 

Columbia, while less important runs exist in the United 

States in the Baker, Columbia, Cedar, Quinault, and 

Ozette Rivers in Washington State (Figure 2). The 

Fraser River (Figure 3) includes a number of important 

nursery lakes and many tributaries that support the 

major portion of the sockeye salmon population in the 

Pacific Northwest. The principle sockeye rearing lakes 

on the Fraser River are Cultus, Adams, Harrison, 

Horsefly, Shuswap, and Quesnel Lakes. In eastern 

Washington, the major nursery lakes for the Columbia 

River are Lake Wenatchee on the Wenatchee River and 

Osoyoos Lake on the Okanogan River. There are eight 

separate geographic stocks of Columbia River sockeye 

that home to specific rearing lakes (Mullan 1986). In 

western Washington the major nursery lakes are 

Quinault Lake on the Quinault River, Ozette Lake on 

the Ozette River, Baker Lake on the Baker River, and 

Lake Washington into which the Cedar River flows 

(Poe and Mathisen 1981). Landlocked populations of 

sockeye salmon, called kokanee, have been 

successfully introduced into many western states 

(Wydoski and Whimey 1979; Wydoski and Bennett 

1981). 

MORPHOLOGY/IDENTIFICATION AIDS 

Dorsal fin (11-16 rays), adipose small, slender and 

fleshy, anal fin (13-18), pelvic fins (9-11) abdominal in 

position with a free-tipped fleshy appendage above its 

insertion, pectoral fins (11-21). Cycloid scales. Gill 

rakers (2943) long, rough, slender, and closely set on 

first gill arch. Body elongate with moderate lateral 

compression. 

Greenish-blue coloration with fine black speckling on 

the back. No large dark spots. Breeding male with pale 
WASHINGTON 

Ocean caught salmon which are exclusively 

of Washington and British Columbia origin 

Ocean or saltwater catch area 

the mid-Columbia 

KILOMETERS 

Figure 2. Major rivers and lakes supporting sockeye salmon in the Pacific Northwest. 

2 
Figure 3. Major sockeye salmon rearing lakes in the Fraser River, Rivers Inlet, and Smith Inlet systems 

of British Columbia (after Poe and Mathisen 1981). 
green head, bright red body, and red fins. Breeding 

female generally the same with characteristic bright 

scarlet body. In juveniles the parr marks are shorter than 

the diameter of eye, oval and usually above lateral line. 

Hart (1973) and Scott and Crossman (1973) are the 

source of morphology and identification aids. 

REASON FOR INCLUSION IN SERIES 

Sockeye salmon are found in commercial quantities 

along the North American coast from the Columbia 

River, between Oregon and Washington, to Bristol Bay, 

Alaska, and are the most valuable commercial fishery in 

both Alaska and British Columbia. They are extremely 

important as subsistence and ceremonial fish to the 

Indians of Alaska, British Columbia, and Washington. 

The brilliant red flesh of these fish is highly desired by 

both commercial and sport fishermen. 

LIFE HISTORY 

Spawning 

Sockeye salmon are anadromous, spending 1-4 years 

in the ocean, usually 2, and 2 years in freshwater. This 

gives a complex number of life cycle years. With the 

onset of maturity, sockeye travel from their oceanic 

feeding areas to their natal streams which are usually 

associated with lakes. After ascending a river, they 

spend 1-8 months in the lake before moving to their natal 

spawning areas. There appears to be a die1 migration 

pattern that operates during migration, and this probably 

differs between stocks (Manzer et al. 1984). Spawning 

areas selected by the adults may be (1) in streams 

flowing into the lake; (2) in the upper sections of the 

lake's outlet river; or (3) along the shores of the lake 

where seepage outflows, springs, or wind-induced waves 

occur (Foerster 1968). 

Redds are selected in areas of gravel bottom where 

there is sufficient waterflow through the gravel to 

provide the developing eggs and embryos with oxygen 

and to remove the waste products of metabolism 

(Foerster 1968). A redd consists of 3-10 nesting pockets, 

each with an average of 750 eggs (Hart 1973). In 

general, medium- to small-sized gravel (1.3-10.2 cm 

according to Reiser and Bjornn 1979) is utilized for redd 

production. Olsen (1968) has indicated that either sand or 

gravel may be used by sockeye salmon, depending upon 

which is available. If small amounts of silt, detritus, or 

fine sand are mixed with the coarser gravel, they are 

removed by the fish in the process of excavating the redd 

(Foerster 1968). The male takes little part in redd 

building, although he remains near the redd for courtship 

purposes. The female excavates the redd by vigorous 

upward and downward motions of her body, causing both 

the tail and water pressure to move the sand and gravel. 

When spawning occurs, the female places herself over 

the pocket, followed by the male a second or two later. 

Both fish lower their tails to bring their vents close 

together near the center of the pocket. Eggs and milt are 

then released while the two fish remain over the pocket 

for 4-19 seconds. Immediately after spawning, the eggs 

are buried by the female (Mathisen 1955). Mathisen 

(1955) observed 198 redds with Bristol Bay sockeye 

spawning in them at Pick Creek and found egg 

concentrations 6-9 inches below the gravel surface. 

Spawning occurs between August and January, 

depending upon the sockeye stock. Adults die after 

spawning. Adult spawning escapement can be assessed 

by several methods including aerial surveys, test 

fisheries, or hydroacoustics (Thome 1979; Cousens et al. 

1982). 

Eggs and Fecundity 

The number of eggs per female varies directly with the 

size of the fish, but there is good evidence that this 

relationship may vary appreciably between stocks of 

sockeye (Foerster 1968; Manzer and Miki 1986). 

Coastal stocks are 18% more fecund than interior stocks 

in British Columbia. The number of eggs is high 

compared to other species (averaging about 3,500 per 

female; Manzer and Miki 1986). However, the size of 

the eggs (5.29-6.60 mm in diameter) is the smallest 

among the Pacific salmon (Foerster 1968). High 

fecundity in sockeye is thought to be related to the long 

period that they spend in freshwater (Foerster 1968). 

The fecundity of Pacific Northwest sockeye is reported 

to vary among females depending upon body size (Table 

1; Manzer and Miki 1986) and not age. There is not any 

relationship of age to fecundity once size is accounted 

for. 
Table 1. Fecundity of sockeye salmon in relation to AlevinsandFry 

size, for various areas (adapted from Foerster 1968). 

Mean length Mean egg 

Area Year (cm) content 

Babine Lakea 1946 

1947 

1949 

Lakelse Lakea 1939 

1948 

1949 

Pick Creek, Wood Riverb 1948 

1950 

1951 

1952 

Kurile Lake. Kamchatkac 

River spawners 1929 

River spawners 1930 

Stream spawners 1932 

Lake spawners 1932 

Lake Dalnee, Kamchatkae - 

Lake Blizhnee, KamchatkaC - 

Pon John, B.C. 1949(18)' 

1950(9) 

1951(5) 

1952(7) 

1953(8) 

1954(9) 

1955(15) 

1956(15) 

1957(5) 

1958(14) 

Karluk Lake, Alaska 1938-41(53)g 

1938-41(63) 

1938-40-41(61) 

1939.1941(74) 

The egg incubation period depends on water 

temperature (4.4-13.3 'C) and usually lasts 50-140 days 

(Scott and Crossman 1973). The development rate of 

sockeye salmon eggs from the fall to spring increases 

with temperature. They develop normally between 4 and 

14 'C (Reiser and Bjomn 1979). After hatching, the 

young (alevins) remain in the gravel for 3-5 weeks 

before emerging as free-swimming fry (Hart 1973). The 

fry emerge in April or May depending on water 

temperature. Each population exhibits inherent 

directional and rheotactic preferences that guide them to 

their nursery lake and disperse them within the lake 

(Brannon 1982; Quinn 1982a). 

They also are extremely light-sensitive and remain at 

the bottom hiding under stones and debris during 

daylight hours (Foerster 1968; Stober and Hamalainen 

1979). They begin moving about at dusk and rise up into 

the flowing water at night. This behavior readily 

facilitates downstream movement into lakes for those 

sockeye salmon which hatch in streams above lakes. 

The fry, which must move upstream to nursery lakes, 

travel during daylight. Clarke and Smith (1972) suggest 

that light, not temperature, is important in stimulating 

upstream movement of fry. Quinn (1982b) indicated that 

sockeye salmon may possess an innate sun orientation 

mechanism. Migrations of juvenile sockeye salmon are 

aided by compass directional preferences that are based 

Cultus Lake, B.C. 1932 58.5 4310 on a combination of celestial and magnetic guidance 

1933 56.5 3796 mechanisms (Quinn 1982b; Quinn and Brannon 1982). 

1934 59.0 4282 

1935 59.0 4067 

1937 56.0 3864 

1938 58.5 4246 Observations in British Columbia of the relative lack 

'No segregation according to age. Probably mostly 52 fish. According to of upsmeam m~v€ment by sockeye fry at night indicated 

Foskett (1956). Skeena River sockeye in these years were 70, 82, and a need for visual contact with the river bottom (Clarke 

76% 52 fish. respectively. and Smith 1972). Mccart (1967) observed that with 

b~oth 42and 52 fish involved. upstream migrating fry there is an initial downstream 

'Egg counts not correlated direclly with length of females. Hence, mean 

length of females. as recorded for the sockeve examined at the mwth of movement* a period of and an eventual return ---- -------------, -~ ~ ~ -- < ~~ 

the Ozemaya River, are used. No age separation has been made. upstream. Upstream movement does not generally begin 

d~nly four individuals in the sample. until the mean daily water temperature exceeds 8 'C 

'Only ranges in length and egg content available. For lengths, males and (M~c~ 1~7). ~~~i~~ the holding period, when fry are 

females are combined. Neither for length nor egg content is there any 

segregation according to age. Several year-classes are involved. concentrated in a narrow ship along the edges of the 

'~igures in parentheses indicate the number of specimens. stream, there is a high mortality due to predation by other 

gFigures in parentheses indicate the age of the fish on the Gilben system. fish (McCart 1967). 
Lake Residence 

Upon entering the nursery lake, sockeye salmon in 

some lake systems move along the shore for a few 

weeks, and then move out over deeper water where they 

concentrate initially at depths of 10 to 20 m (Hart 1973). 

During the period of lake residence, fry are pelagic 

schooling fish that subsist mainly on zooplankton. Die1 

vertical movements include rising into the surface layer 

at dusk, descending slightly at night, and then at dawn 

descending to dceper daytime depths (McDonald 1969; 

Narvcr 1970; Woodcy 1972). 

Dicl migration in lhermally stratified lakes increases 

the growth rate because of exposure to a 24-hour cycle of 

variation in temperature. Sockeye fed moderate amounts 

of food in the laboratory and exposed to daily cyclic 

tempcrature change had the highest gross growth 

efficiency (ration of growth lo total food ingested) and 

growth rate compared to fish exposed to constant high or 

low temperatures (Biette and Geen 1980a). Constant 

high temperatures result in slower growth because of 

energy loss from a high respiration rate, and low 

lemperatures retard growth because they cause a high 

defecation and excretion rate (Biette and Geen 1980b). 

However, the migration to greater depths during the day 

has he disadvantage that the fish are out of the lighted 

zonc where they can visually fced. They may move 

decpcr during the day to avoid predators that hunt 

visually. Howevcr, they fced crepuscularly (at dawn and 

dusk), perhaps taking advantage of a tradeoff bctween 

optimal sunlight conditions for their own feeding on 

zooplankton and optimal light conditions for predation 

on Lhc sockeye by larger fish (Clark and Levy 1988). 

Young sockeye salmon normally live in the nursery 

lake for 1 or 2 years, while in some regions of Alaska 

this is for 3 ycars, and on rare occasions this residence 

may last 4 years (Miller and Brannon 1982). In British 

Columbia this residence is usually only 1 year (Scott and 

Crossman 1973). This residence time is generally 

greater the farlhcr north geographically that the nursery 

area is located. This pcriod is a very crucial stage in 

sockeye natural production, one in which mortality may 

be very high due lo piscivorus prcdation (Foerster 1968). 

Mortality of young fry is size selcctive, with those that 

were smallest at the time of cmcrgcnce having a lower 

survival (West and Larkin 1986). When surface 

lempcralures in the nursery lakes approach 4 to 7 "C in 

the spring, most 1-year resident sockeye migrate to sea 

(Hart 1973). Fish which are larger or that have been in 

the lake for 2 years tend to migrate earlier. Observations 

in the Wood River system of Alaska indicated that 

seaward migration of young sockeye was consistently 

temperature-related (Burgner 1958). Foerster (1968) 

observed that cessation of migration seemed to be 

associated with temperatures of 4.4 to 5.0 "C in the 

upper waters of Cultus Lake, British Columbia. Rees 

(1957) found that downstream migrant sockeye smolts in 

Baker Lake, Washington, clearly occupied the surface 

layer (water down to 4-5 m), and lhat fish density 

decreased with increasing depth with almost no fish 

observed below 14-15 m. Migration to the sea includes 

active downstream swimming in quiet river reaches, but 

is passive and tail first in rapids (Hart 1973). This 

migration to the sea is rapid (Miller and Brannon 1982). 

Saltwater Life 

In the Pacific Northwest, sockeye salmon smolts enter 

the ocean primarily from Puget Sound, the Quinault 

River on the Olympia Peninsula, the Columbia River in 

Washington, and the Fraser River in British Columbia 

(Figure 2). Stocks from the soulhern locations 

apparently enter the ocean first, followed by stocks in the 

more northcrn and western locations, while the migration 

in the Strait of Juan de Fuca peaks prior to July (Hartt 

1980). Upon entering the marine environment, sockeye 

salmon proceed immediately to the feeding grounds of 

the high seas (Eggers 1982). Unlike other Pacific 

salmon species, young sockeye salmon are not often seen 

in estuarine and inshore waters after reaching the marine 

environment (Miller and Brannon 1982). Catches of 

juveniles originating in the Strait of Juan de Fuca 

indicate that they migrate along the coastal belt, 

preceding juvenile chum and pink salmon. It is well 

known lhat sockeye salmon travel far during the marine 

phase of their life, most notably to the northern, 

nutrient-rich waters of Alaska and the Arctic (Hartt 1980; 

Brannon 1982). There is evidence of a general 

intermingling in the Gulf of Alaska region during much 

of the marine phase. Frcnch and McAlister (1970) 

observed lhat the distribution of sockeye salmon in 

various areas of the Northwestern Pacilic Ocean seemed 

to depend on agc and maturily rather than on place of 

origin. For example, stocks from Brislol Bay, which 

contribule a significant proporlion of thc Norlh Amcrican 

sockeye fishery, and non-Bristol Bay stocks were found 
to have a similar distribution in areas of the northeastern 

Pacific Ocean during the winter (French and McAlister 

1970). Sonar observations and gillnet catches show that 

salmon, rather than forming defhed schools, disperse 

during their feeding periods in the ocean (Burgner 1980). 

Detailed information on the distribution of sockeye 

salmon in the north Pacific Ocean obtained from 

commercial fleets and research vessels was discussed by 

French et al. (1976). Sockeye salmon spend a total of 

1-4 years as marine residents. 

High seas migrations of salmonids and the 

mechanisms which guide them remain largely unknown. 

Quinn (1982b) stated that the relative densities of food, 

predators, and competitors are undoubtedly important, as 

well as currents, water temperature, and salinity. It was 

further proposed that salmon navigate using a celestial 

compass with a backup magnetic compass, the 

inclination and declination of the earth's magnetic field, 

and an endogenous circannual rhythm adjusted by the 

length of the day or photoperiod (Quinn 1982b). 

Salmon-guiding mechanisms were further discussed by 

Leggett (1977) and Brannon (1982). 

Statistical model predictions have suggested that about 

90% of the natural mortality in the ocean occurs during 

the first 4 months that sockeye salmon are at sea (Furnell 

and Brett 1986). The marine survival rate varies with 

smolt size and probably varies with geographic region. 

Ames (1983) stated that marine survival ranged from 

4%-20% with an average of 9.8 adults returning to the 

Cedar River for each of 100 pre-smolts, a normal range 

of survival for sockeye salmon stocks. Thorne and Ames 

(1987) also report marine survival of 4%-20% for Lake 

Washington sockeye. 

GROWTH CHARACTERISTICS 

Sockeye salmon growth rates may vary in different 

parts of the same nursery lake (Pella 1968). In Lake 

Aleknagik, Alaska, fry in the eastern end of the lake were 

significantly larger than those in the western end. If 

salmon fry from both ends of the lake had hatched at the 

same spawning grounds in the western end, salmon fry 

which had migrated to the eastern end would be larger 

because they had hatched earlier and had a longer 

feeding period during migralion to the other end of the 

lake. Fry at the western end would be smaller because of 

a more recent hatching and shorter feeding period. 

Growth rates of sockeye fry varied considerably more in 

the littoral zone (0.158-0.349 mm per day) than in the 

limnetic zone (0.233-0.292 mm per day), according to 

Pella (1968). In the first 12 months of life, the growth of 

fry has been shown to be related to both the temperature 

(optimum 15 'C) and the amount of ration available as a 

percent of dry body weight per day (Brett et al. 1969). 

As the available ration was decreased from 6% to 1.5% 

in laboratory experiments, the optimum temperature 

shifted downward from 15 to 5 'C. 

Sockeye fry migrate from their rearing lakes at various 

sizes (Foerster 1968), with 1-year-old migrants varying 

from 6.0 to 11.5 cm in length and 2.0 to 15.5 g in weight; 

2-year-old migrants varying from 7.6 to 15.6 cm and 

18.0 g to 39.1 g; and 3-year-old fish varying from 10.0 to 

14.2 cm and 21.0 g to 26.5 g. Although young sockeye 

salmon will migrate out at all three ages, in Alaska they 

migrate primarily at age-I or age-11, and in British 

Columbia they migrate primarily at age-I (Foerster 

1968). One-year-old migrant fish in British Columbia 

have an average length and weight size of about 8 cm 

and 5 g. Hyatt and Stockney (1985) found 1-year-old 

smolts weighing less than 2 g in 7 populations of 

sockeye salmon along the British Columbia coast. The 

presence of competitor and predator fish as well as the 

density of the sockeye fry themselves will have an effect 

on the growth rate (Foerster 1968; Pella 1968; Hyatt and 

Stockner 1985). Studies on the role of density in 

regulating growth have generally been between-lake, 

between-year comparisons. Growth appears to be 

depressed in areas of heavy sockeye fry density, but Pella 

(1968) has advanced an alternative hypothesis that the 

largest of the sockeye fry were the first to leave the 

crowded rearing areas, thereby leaving only smaller fish. 

Geography plays an important role in growth: in British 

Columbia, outer coastal lakes generally produce smaller 

smolts than do the more productive interior lakes 

(Stockner and Shortreed 1983). 

Hartt (1980) stated that sockeye salmon usually reach 

a minimum of 10 cm before they are found in the ocean 

migration routes. Smolts that enter the marine 

environment are smaller than 10 cm. Addition of 

nitrogen and phosphorus fertilizer to British Columbia 

coastal lakes increased production of zooplankton, 

causing increased in-lake growth of juvenile sockeye 

salmon and larger outmigrant smolts (Stockner and Hyatt 
1984; Hyatt and Stockner 1985). In fertilized lakes, the in the sea have a slower overall growth rate; and (3) 

average weight at migration was 3.8 g, while in sockeye that spend only 1 year and a few months in the 

unfertilized lakes the average weight at migration was sea but that are a total of 3-5 years old have had growth 

2.3 g. during the second summer in the ocean that is twice that 

of other fish. Fast growth during the early period of 

The major fingerling growing season includes July, marine life tends to be associated with an earlier age of 

August, and September. Growth in the second season maturity (Peterman 1985). 

begins prior to or at the time of seaward migration of 

yearlings. Mean size of first year sockeye caught in 

marine waters in the northeastern Pacific Ocean ranged THE FISHERY 

from 12 to 20 cm (Hartt 1980). In a study of British 

Columbia sockeye stocks, Ricker (1982) stated a positive Forecasting Models 

correlation between length of oceanic life and final size. 

The commonly used linear forecasting method 

overestimated sockeye runs more often than a nonlinear 

Smolt-size increases in ferlilized lakes will lead to method for Bristol Bay, Alaska, salmon and the nonlinear 

increases in both marine survival and an earlier age of method is recommended. Overestimates of returning 

returning adults, thereby increasing the harvestable sockeye may lead to overharvesting and hence reduced 

surplus of sockeye adults (Hyatt and Stockner 1985). long-term yield, and may also result in overinvestment in 

Lake fertilization has also been correlated with increased the fishery by participants (Bocking and Peterman 1988). 

egg-to-juvenile survival of sockeye salmon as well as 

greatly increased adult returns (Le Brasseur et al. 1978). Puget Sound Stocks 

The fish grow to a maximum reported length of 84 cm in 

the ocean, but stocks from different river systems have Commercial catches of sockeye salmon peaked in the 

characteristic sizes (Foerster 1968; Hart 1973). late 1930's for both North American and Asian stocks 

According to Foerster (1968), sockeye salmon growth (Figure 4) (French et al. 1976). North American stocks 

rate during ocean residence is governed by three factors: originate primarily from streams and lakes in Alaska and 

the amount of food (principally plankton) available; British Columbia; the most important producing area is 

water temperature (growth is generally faster in warmer western Alaska (Figure 5), especially the tributaries of 

water); and the degree of competition for food and size Bristol Bay (French et al. 1976). The Japanese high seas 

of the feeding salmon. However, Ricker (1982) noted gillnet fishery harvests sockeye salmon of both Asian 

that adult sockeye appear to grow larger in years of and North American origin. The Canadian commercial 

sub-average marine temperatures. Adult body size and harvest comes from fish originating primarily from 

growth rate decrease when sockeye salmon are abundant British Columbia, while a significant portion of the 

in the Gulf of Alaska (Peterman 1984). Weight Washington State commercial catch originates from the 

differences can amount to 10%-22% at high abundance Fraser River in southern British Columbia (French et al. 

of conspecifics. Density-dependent effects arise mainly 1976). Catches of sockeye salmon in Washington and 

during early ocean life and are probably due to Oregon have averaged about 1 million fish in recent 

competition for food (Peterman 1984). Thus, years (French et al. 1976). 

fluctuations in growth are to be expected from year to 

year which result in different lengths and weights of the Two sockeye salmon runs originate in the Puget Sound 

fish at maturity. basin (Figure 2)--one in Lake Washington and one in 

Baker Lake. The larger of the two runs is from Lake 

There are some general consistencies in sockeye Washington, where most of the fish spawn in the Cedar 

growth according to Foerster (1968) which are as River. This stock was introduced by plantings of fry, 

follows: (1) the length increment in the second ocean fingerlings, and yearlings from Baker Lake, Washington, 

year is appreciably less than in the first and is less in the between 1935 and 1945 (Kolb 1971), and is now the 

third ocean season than in the second; (2) among fish of largest sockeye salmon run in the United States outside 

the same freshwater age, those that spend a longer time of Alaska (Stober and Hamalainen 1979). The 
1910 '15 '20 '25 '30 '35 '40 '45 '50 '55 '60 '65 '70 '75 

YEAR 

Figure 4. Estimated commercial catch of sockeye salmon in Asia, North America, and the Japanese 

mothership fshery, 1909-71 (after French et al. 1976). 

USSR. 

Figure 5. Average annual commercial catch of sockeye salmon in important coastal and high seas fshing 

areas, 1961-71 (after French et al. 1976). 
population is first predicted by presmolt numbers 

(pre-season forecast), and adult returns are then 

monitored at the Ballard Locks in June and July to 

update the earlier estimates. The escapement goal of 

350,000 spawners for Lake Washington has been in 

effect since 1969 (Ames 1983; Puget Sound Tribes et al. 

1989). Both escapement and the resulting adult run size 

have increased between 1968 and 1983 (Table 2; Ames 

1983). Three identifiable fisheries exploit the Lake 

Washington stock: (1) a Puget Sound non-Indian 

commercial fishery using gillnets and purse seines; 2) an 

Indian gillnet fishery; and 3) a sport fishery (Bryant 

1976). Until the early 1970's, Lake Washington sockeye 

salmon were managed exclusively for the commercial 

fishery. In recent years, however, the tribal and sport 

fisheries have taken the greatest number of fish. The 

highly successful sport fishery provides an excellent 

economic return while having little effect on escapement 

Table 2. Lake Washington sockeye brood year data (adapted from Puget Sound Tribes et al. 1989). 

Peak Presmolt 

Cedar River population 

Brood flow (ft3/s) estimate 

year Escapement Renton (X 104 

1964 137,500 5,300 

1965 132,000 1,570 

1966 123,000 2,960 

1967 383,000 2,9 10 7.50 

1968 252,000 3,720 3.19 

1969 200,000 2,290 3.80 

1970 124,000 2,730 2.00 

1971 183,000 8,160 1.70 

1972 249,000 4,000 3.58 

1973 330,000 4,220 4.56' 

1974 126,000 3,520 1.96' 

1975 120,000 8,800 1.14 

1976 159 ,OOOd 1,340 3.96 

1977 275,000 5,670 2.93 

1978 290,000 1,840 6.80 

1979 206,000 3,080 3.64 

1980 36 1,000 3,020 3.78 

1981 107,000 5,320 1.14 

1982 289,000 3,250 2.02 

1983 227,000 5,540 1.32 

1984 372,000 1,610 4.99 

1985 254,000 2,4 80 0.95 

1986 249,000 5,070 0.73 

1987 207,000 1,820 

1988 376,000 

Resulting 

adult 

run sizea 

274,165 

267,338 

135,224 

559,074 

299,461 

476,191 

149,649 

143,578 

179,915 

593,148 

311,266 

229,787 

497,322 

119,304 

323,988 

290,40 1 

477,87 1 

261,779 

257,542 

22253 1 

645,980 

Freshwater 

survival (pre- Percent 

smolts per marine 

Jacks spawner) survivalb 

Return1 

spawner 

1.99 

2.03 

1.10 

1.46 

1.19 

2.38 

1.21 

0.78 

0.72 

1.80 

2.47 

1.91 

3.13 

0.43 

1.12 

1.41 

1.32 

2.45 

0.89 

0.99 

1.74 

Average 229,260 3,759 3.08 319,171 7,672 12.96 9.23 1.41 

a~ncludes jacks from next brood year. 

bThese values assumc returns are 4-year-old fish only. 

'Accurate presmolt estimates unavailable. Values used are estimated from the relationship between freshwater 

survival (presmolt pcr spawner) and peak floods on the Cedar River. 

d~ctual escapement 435,000 fish. hespawning mortality reduced effective escapement to 275,000 sockeye. 
(Bryant and Mathews 1973). The recent increase in the 

tribal fishery is due to a 50:50 sharing plan brought about 

by United States v. Washington (Clark 1985). Lake 

Washington sockeye brood-year data for 1964-79 

indicates an average escapement of 212,970 sockeye. 

The other run which originates in the Puget Sound 

basin spawns on beaches of Baker Lake above the 

hydroelectric reservoir on the Baker River, a tributary of 

the Skagit River (Figure 2). The sockeye salmon are 

trapped at facilities near the mouth of the Baker River 

and trucked upstream to the spawning beaches. Because 

of the recent average escapements of less than 2,000 

sockeye salmon (Table 3), and an escapement goal of 

4,500 fish, management recommendations in recent 

years have called for no targeted Baker River sockeye 

fishery (Puget Sound Tribes et al. 1989). 

Full utilization of the Baker River as a sockeye salmon 

production area would require improvements to the 

downstream juvenile passage facilities to ensure that 

more fish get past the two hydroelectric dams that are 

present (Puget Sound Tribes et al. 1989). No sport or 

commercial saltwater fisheries are directed at the Baker 

River sockeye salmon run. Sockeye fisheries in northern 

Puget Sound and the Strait of Juan de Fuca take place 

only when there are harvestable surpluses of British 

Columbia's Fraser River sockeye salmon available 

(Puget Sound Tribes et al. 1989). The impact of the 

mixed stock fishery on the Baker River stock then is 

minimal. 

Table 3. Terminal area catch and escapement for Baker River (Skagit 

system) sockeye (data adapted from Puget Sound Tribes et al. 1989). 

Baker trap Terminal Terminal Returns1 

Year escapement catcha run size spawner 

b 

1967 4,121 784 4,905 

1968 3,022 448 3,470 

1969 1,295 306 1,601 

1970 82 1 30 85 1 

197 1 2,93 1 1,095 4,026 0.98 

1972 10,03 1 641 10,672 3.53 

1973 3,656 1,109 4,765 3.68 

1974 3,611 1,069 4,680 5.70 

1975 1,303 686 1,989 0.68 

1976 1,518 65 1 2,169 0.22 

1977 1,707 387 2,094 0.57 

1978 2,716 668 3,384 0.94 

1979 865 535 1,400 1.07 

1980 499 46 545 0.36 

1981 208 264 472 0.28 

1982 1,860 287 2,147 0.79 

1983 735 172 907 1.05 

1984 358 17 375 0.75 

1985 92 410 502 2.4 1 

1986 542 39 58 1 0.3 1 

1987 69 1 84 775 1.05 

1988 818 62 880 2.46 

a~ncludes both treaty and non-treaty catches and Skagit Bay and Skagit River. 

b~rood year = year-4. 
Columbia River Stocks 

There has been no significant commercial harvest of 

sockeye salmon on the Columbia River system in recent 

years (Allen 1977). Historically, the Columbia basin 

catch which peaked between 1890 and 1900 was highly 

variable from year to year (Figure 6). The impoundment 

of the Columbia River for power and irrigation has 

reduced the river's current velocity and caused a rise in 

water temperatures, which among other factors, has 

harmed the native sockeye salmon runs. Declining runs 

in this river can be correlated with increased number of 

dams (Mullan 1986). The primary sockeye salmonproducing areas of the Columbia River basin are Lake 

Osoyoos on the Okanogan River system between 

Washington and British Columbia and Lake Wenatchee 

on the Wenatchee River system in Washington (Allen 

and Meekin 1973; Poe and Mathisen 1981; Mullan 

1986). These runs have been partly sustained by stocked 

fish from the Federal hatchery at Leavenworth, 

Washington. Approximately 14% of the fish taken in 

commercial and Indian fisheries in the lower Columbia 

River originated from this hatchery (Wahle et al. 1979). 

These two runs are sustained by releasing hatchery 

fingerlings into the Wenatchee and the Okanogan Rivers 

(Davidson 1966). Natural reproduction does occur with 

these two stocks (Peven 1987); however, both returning 

adults and out-migrating smolts must pass nine dams on 

the midColumbia River (Peven 1987). 

Figure 6. Commercial catches of blueback salmon in the Columbia River 1889 to 1965. Adapted from 

Craig and Hacker (1940) and Davidson (1966). 
North Coastal Stocks 

On the North Pacific Coast of Washington State there 

are two sockeye producing areas: Lake Quinault and 

Lake Ozette (Poe and Mathisen 1981). The Quinault 

Indians are the exclusive harvesters of Lake Quinault 

sockeye salmon in a tribal gill-net fishery that averages 

27,500 fish per year, according to the Pacific Fishery 

Management Council (1983). Lake Ozette was once a 

moderate producer of sockeye salmon and supported a 

fishery by the Makah Indian Tribe that yielded over 

17,500 fish in 1949 and approximately 15,000 fish in 

both 1950 and 1951, but subsequently declined to zero in 

both 1974 and 1975 (Blum 1984). In recent years the 

Lake Ozette fishery has averaged only about 30 fish per 

year (Blum 1984). Investigations into the limiting 

factors that may have caused this spectacular decline 

were investigated by Dlugokenski et al. (1981) and Blum 

(1984). Restoration of the Lake Ozette sockeye fishery 

will be attempted through the use of an introduced 

sockeye stock that will utilize the lake's tributaries to 

spawn. The native stock only utilizes the suitable part of 

the lake shore, which is currently extremely limited in 

area (Blum 1984). 

ECOLOGICAL ROLE 

Juvenile sockeye salmon are pelagic, schooling fish 

and are largely planktivorous. Their primary foods 

depend on the availability of seasonal zooplankton 

populations (Foerster 1968; Woodey 1972). Studies in 

Lake Washington revealed that the primary foods of 

sockeye salmon were the copepods, Epischura, 

Diaptomus, Cyclops, and the cladoceran, Diaphanosoma 

(Woodey 1972; Eggers 1978). In nursery lakes of British 

Columbia, common foods of young sockeye salmon 

include Cladocera (Bosmina and Daphnia) and copepods 

(Cyclops and Epischura) (Foerster 1925,1968). Cyclops 

constituted the main food item (85%), followed by 

Daphnia (12%) and Bosmina (3%), while Epischura was 

encountered only rarely (Foerster 1968). Young sockeye 

salmon are active and important predators of the 

planktonic crustaceans, and they may be selective for 

size and species (Foerster 1968). 

Threespine stickleback (Gasterosteus aculeatus) and 

juvenile sockeye salmon in the littoral zone of Great 

Central Lake exhibited considerable dietary overlap, 

especially during late spring and summer (Manzer 1976). 

However, since the salmon and sticklebacks occupy the 

littoral zone at different times of the year, interspecific 

competition for food in the lake is probably not serious, 

especially in years when food is abundant (Rogers 1968; 

Manzer 1976). In localities where the ratio of fish to 

food is unfavorable, the growth rate of both species is 

reduced (Rogers 1968). 

Eggers (1977, 1982) believed that three factors 

governed prey selection by planktivorous fish: (1) 

differential rates of prey encounter due to differences in 

prey visibility; (2) differential rates of prey capture 

efficiency; and (3) optimal foraging where the predator 

ignores certain small and inferior prey types to increase 

the time available to search for larger, more valuable 

prey. Beacham (1986) also indicated that sockeye diet 

variability may be due to prey abundance and selection 

by the predator, as well as the possible selectivity of the 

sampling gear used. Juvenile sockeye salmon may show 

size-selective predation by shifting their pursuit to the 

larger zooplankton forms if sufficiently abundant, 

prefemng the larger over the smaller zooplankton forms 

(Foerster 1968; Eggers 1978,1982; Beacham 1986). 

Daily feeding of young sockeye salmon is heaviest in 

the afternoon and lightest during the night and early 

morning (Northcote and Lorz 1966; McCart 1967; Doble 

and Eggers 1978). Their most intensive feeding period is 

in August and September, followed by a low in winter, 

when the stomachs of a considerable number of the fish 

population empty (Woodey 1972; Doble and Eggers 

1978). Feeding rates increase again in February and 

March (Foerster 1968; Eggers 1978). 

Lake Washington juvenile sockeye salmon show 

consistent seasonal and die1 patterns of vertical 

movement (Eggers 1978). Die1 vertical movements have 

been observed in other sockeye populations (Northcote 

and Lorz 1966; McDonald 1973). They generally consist 

of an ascent into surface layers at dusk and a descent to 

greater depths after dusk, and to even greater depths after 

dawn (Eggers 1978). In Lake Washington, the mean 

depth of the population increases progressively deeper 

from June through February, but the fish again move 

higher in the water column as smoltification approaches 

(Eggers 1978). 
Throughout the summer to fall growing season, young 

sockeye in Lake Washington form schools (Woodey 

1972) that disperse as dusk approaches and re-form as 

light increases after dawn (Eggers 1978). During the 

winter, sockeye do not school, but they resume this 

behavior during the presmolt growth period before 

migration (Eggers 1978). Eggers (1978) hypothesized 

these complex behaviors as a response to avoid predation 

by such visual predators as the northern squawfish, 

Ptychocheilus oregonensis, and to meet energy 

requirements. British Columbia sockeye salmon also 

showed similarly complex feeding and movement 

behaviors. 

The food spectrum of sockeye salmon in the ocean is 

relatively wide, and substitute organisms are consumed if 

a favored food item is lacking (Foerster 1968; Beacham 

1986). However, the variability of prey items eaten by 

sockeye salmon is much less than that of either pink 

salmon, chinook salmon, or coho salmon (Beacham 

1986). There was very little difference in the diet of 

sockeye salmon that are 7 cm or 55 cm in the Strait of 

Juan de Fuca (Beacham 1986), where the diet was 

mainly euphausiids with lesser diet components 

comprised of crab larvae, mysids, the hyperiid amphipod 

Parathemisto, and the Pacific sand lance Ammodytes 

hexapterus. Of the four species of salmon studied by 

Beacham (1986), sockeye salmon were the least 

piscivorous. He concluded that morphological 

differences among the four species (sockeye salmon have 

the largest number of gill rakers) account for a greater 

partitioning of the diet than do differences in water 

depths in which the individual species live. Dell (1963), 

who examined sockeye salmon stomachs taken off 

research vessels in the Northeastern Pacific Ocean, south 

of the Aleutian Islands, observed that euphausiids were 

the most abundant single food item by volume among 

immature fish, but were of minor importance in mature 

fish. More amphipods and fish were eaten by mature 

sockeye salmon than by immature fish (Dell 1963). 

Sockeye salmon of all ages feed heavily on euphausiids, 

hyperiid amphipods, copepods, cladocerans, pteropods, 

tunicates, and squid during their ocean residence 

(LeBrasseur 1966; Foerster 1968). 

Predators of juvenile sockeye salmon include yearling 

coho salmon Oncorhynchus kisutch, cutthroat trout, 

Salmo clarki; Dolly Varden, Salvelinus rnalma; Arctic 

char, Salvelinus alpinus; prickly sculpin, Cottus asper; 

northern squawfish; and smolts of rainbow trout and 

steelhead, Salmo gairdneri (Foerster and Ricker 1941; 

Ward and Larkin 1964; Thompson and Tufts 1967; 

Ginetz and Larkin 1976; Eggers et al. 1978; Ruggerone 

and Rogers 1984). Studies of Lake Washington fish 

populations show that northern squawfish are a 

significant predator of young sockeye (Bartoo 1972; 

Eggers et al. 1978; Beauchamp 1987). Ward and Larkin 

(1964) found that rainbow trout preyed heavily upon 

juvenile sockeye in the western region of Shuswap Lake, 

British Columbia, and when juvenile sockeye were 

scarce, the condition of the trout population was 

relatively poor. Predation mortality of sockeye salmon 

caused by both rainbow trout and Arctic char decreased 

during periods of declining light intensities (Ginetz and 

Larkin 1976; Ruggerone and Rogers 1984). In Lake 

Washington, 2%-5% of the sockeye smolt production 

was lost to rainbow trout predation in 1984-85, with 

longfin smelt (Spirinchus thaleichthys) acting as a buffer 

to higher predation on the young sockeye salmon 

(Beauchamp 1987). Predation on juveniles appears to be 

density related because the number of smolts eaten by 

predators increased as smolt abundance increased 

(Ruggerone and Rogers 1984). 

Qualitative observations of juvenile sockeye salmon at 

sea showed predator scars caused by lampreys, seals, sea 

lions, sharks, and predaceous pelagic fishes such as the 

daggertooth, Anotopterus pharao, (Hartt 1980). 

Predators of adult sockeye salmon include harbor seals 

Phoca vitulina, and killer whales Orcinus orca. Adults 

returning to natal spawning areas are eaten by bears and 

certain large avian predators (Foerster 1968). 

ENVIRONMENTAL REQUIREMENTS 

Temperature 

According to Reiser and Bjomn (1979), the optimum 

spawning temperatures of sockeye salmon range between 

10.6 and 12.2 "C, while incubation temperatures for 

successful hatching are between 4.4 and 13.3 "C. 

Donaldson and Foster (1941) studied the effect of 

various experimental water temperatures on sockeye 

fingerlings and found that between 8.9 to 10.0 "C, the 

growth rate was fastest and mortalities were lowest. 

Low temperatures of 3.9-7.2 "C as well as high 

temperatures above 23 "C produced poor growth, low 
food utilization, and high mortalities (Donaldson and 

Foster 1941). Brett (1952) observed an upper lethal 

temperature of 24.4 'C for young sockeye and a 

preferred range between 12 and 14 'C. In a later paper 

Brett (197 1) indicated that the physiological optimum for 

sockeye salmon was 15 "C, and even though sockeye 

salmon will tolerate 24 "C, they are generally limited in 

the natural environment at temperatures above 18 'C. 

Salinity 

Young sockeye make the usual physiological changes 

observed in all migrating salmon going from freshwater 

to highly saline waters of the marine environment. To 

withstand this change from freshwater to saltwater, the 

young fish undergo a process known as smoltification 

(Wedemeyer et al. 1980). Yearlings retained in 

freshwater beyond their migration time lost their 

preference for saltwater (Baggerman 1960). French et al. 

(1976) found no obvious correlation between sockeye 

salmon distribution and the ocean salinity, since they 

occur at various salinities in the North Pacific Ocean and 

Bering Sea. 

Dissolved Oxygen 

Sockeye salmon eggs require at least 5.0 mg/L 

dissolved oxygen for successful incubation (Reiser and 

Bjornn 1979). Alevins hatched at oxygen concentrations 

of 3.0 mg/L averaged 16.3 mm in length while those 

hatched at 11.9 mg/L averaged 19.7 mm in length 

(Brannon 1965). At temperatures above 15 'C the 

metabolic rate of young sockeye salmon may be limited 

by the oxygen available (Brett 1964). At 15 'C, 

dissolved oxygen levels above 4.2 mg/L do not affect 

growth of juvenile sockeye, but growth ceases at 

2.6 mg/L and bclow (Brett and Blackburn 1981). Brett 

(1970) discussed oxygen requirements for fingerling 

sockeye salmon at 20 'C during various activities and 

reported that a reduction in oxygen to 50% saturation at 

high temperatures severely limited energy available for 

migrating or feeding. Initial distress symptoms may be 

observed in freshwater salmonid populations at a 

dissolved oxygen concentration of 6 mg/L at 

temperatures ranging between 0 and 20 "C, while most 

fish are adversely affected by lack of oxygen at 

concentrations below 4.25 mg/L in the same temperature 

range (Davis 1973). 

Substrate 

Although adult sockeye salmon utilize many habitats 

for their benthic spawning sites, such as river, stream, 

lakeshore, and spring, they generdly select sites with 

medium- to small-sized gravel (F~rster 1968). Reiser 

and Bjornn (1979) listed gravel from 1.3 to 10.2 cm in 

diameter as acceptable for sockeye salmon spawning. 

Excessive amounts of sand and silt in the gravel hindered 

fry emergence, even though the embryos may hatch and 

develop normally (Reiser and Bjornn 1979). No 

substrate preference has been documented for juveniles 

in rearing lakes or for adults in the marine environment. 

Water Depth 

The optimum depth for sockeye salmon spawning is 

0.3-0.5 m (Reiser and Bjornn 1979). As juveniles, 

sockeye salmon are within 20 m of the surface in the 

spring (Mathison and Smith 1982). Rearing juvenile 

sockeye salmon in lakes commonly display diel vertical 

migration throughout the growing season (Eggars 1978). 

Juvenile sockeye salmon in Lake Washington are seldom 

found near the surface and significant numbers do not 

venture above 20 m until spring according to Eggars 

(1978). As smoltification approaches, the young salmon 

again tend to inhabit the upper part of the water column. 

More northerly populations may show greater diel 

vertical migrations. Rees (1957) found that the smolts 

were near the surface during outmigration. 

Water Movement 

Sockeye salmon require enough water flow past the 

developing eggs and embryos to provide oxygen and 

carry away waste. Sockeye spawning areas usually have 

water that is moving 21- 101 cm3/s (Reiser and Bjornn 

1979). During the incubation period of Lake Washington 

sockeye salmon in the Cedar River, maximum 

instantaneous discharges greater than 50 m3/s have 

reduced the survival of these fish (Stober and 

Hamalainen 1979). Velocities of 53-55 cm3/s have been 

measured 0.4 ft above the spawning beds of sockeye 

salmon (Rciser and Bjornn 1979). River flow (peak 

discharge) during spawning and gravel incubation had a 

major positive effect on production of presmolts in the 

Lake Washington stock (Thorne and Ames 1987). 
Turbidity Oil Spills 

Fine sediments that are suspended or deposited in 

salmonid rearing areas can adversely affect salmonid 

populations by clogging fish gills, reducing feeding, and 

causing fish to avoid some arcas (Reiser and Bjornn 

1979). Suspended sediments may cause indirect damage 

by lowering the survival of eggs or alevin and destroying 

food sources (Tanwell 1957; Bjornn et al. 1977). Turbid 

water also absorbs more radiation than clear water and 

may indirectly result in a thermal barrier to migration of 

salmon (Reiser and Bjornn 1979). 

Streams with silt loads averaging less than 25 mg/L 

can be expcctcd to support good freshwater fishcrics, 

while silt loads exceeding 4,000 mg/L may stop the 

upstream migration of adult salmon (Bell 1973). 

The short-term effcct of a tankcr accident in Bristol 

Bay, Alaska (rclcasing 34,000 tons of diesel fuel) on 

rctuming adult sockeye salmon was simulated on a 

computcr. Estimated mortalities would be 2%-18% for 

fish passing through the spill area and 1 %-5% of the total 

stock. From 3% to 7% of thc fish traveling through the 

spill area would probably be tainted with 0.6 ppm or 

greater levcls of hydrocarbons in the flesh. An oil 

blowout (rclcasing 3,000 tonstday of crude oil) would 

cause cstimatcd mortalities of only up to 0.2% of the 

salmon passing through the blowout area. No tainting 

with hydrocarbons above 0.6 ppm was predicted (Bax 

1987). 
REFERENCES 

Allen, R.L. 1977. Status of the upper Columbia River 

salmon and steelhcad runs. Pages 84-88 in E. 

Schwieben, ed. Columbia River salmon and 

steelhead: proceedings of a symposium. Am. Fish. Soc. 

Spec. Publ. No. 10. 

Allen, R.L., and T.K. Meckin. 1973. Columbia Rivcr 

sockeye salmon study, 1972. Progress report. 

Washington Deparuncnt of Fishcrics, Olympia. 

61 PP. 

Ames, J. 1983. Lake Washington sockeye: an example 

of a low productivity salmon stock. Lake Washington 

symposium. Trout Unlimited, Mercer Island, Wash. 5 

PP. 

Baggerman, B. 1960. Salinity prefcrcnce, thyroid activity and the seaward migration of four species of Pacific 

Salmon (Oncorhynchus). J. Fish. Res. Board. Can. 

17(3):295-322. 

Bartoo, B. 1972. The vcrtical and horizontal distributions of northern squawfish (Ptychocheilus 

oregonensis), peamouth (Mylocheilus caurinus), 

yellow perch (Perca j7avescenr), and adult sockeye 

salmon (Oncorhynchus nerka) in Lake Washington. 

M.S. Thesis, University of Washington, Seattle. 

60 PP. 

Bax, N.J. 1987. Effects of a tanker accident and an oil 

blowout in Bristol Bay, Alaska, U.S.A., on returning 

adult sockeyc salmon, (Oncorhynchus nerka)--a 

simulation study. Mar. Environ. Res. 22: 177-204. 

Beacham, T. D. 1986. Type, quantity, and size of food of 

Pacific salmon (Oncorhynchus) in the Strait of Juan de 

Fuca, British Columbia. U. S. Natl. Mar. Fish. Serv. 

Fish. Bull. 84(1): 77-89. 

Beauchamp, D.A. 1987. Ecological relationships of 

hatchery rainbow trout in Lake Washington. Ph.D. 

Dissertation. University of Washington, Seattle. 236 

PP. 

Bell, M.C. 1973. Fisheries handbook of engineering requirements and biological criteria. U.S. Army Corps 

of Engineers, Portland, Oregon. Contract No. 

DACW57-68-C-0086. 425 pp. 

Biettc, R.M., and G.H. Geen. 1980a. Growth of underyearling sockeye salmon (Oncorhynchus nerka) under 

constant and cyclic tcmperatures in relation to live 

zooplankton ration size. Can. J. Fish. Aquat. Sci. 

37:203-210. 

Biette, R.M., and G.H. Geen. 1980b. The fate of 14clabeled food ingested by underyearling sockeye 

salmon, Oncorhynchus nerka, in relation to 

temperature and ration. Can. J. Fish. Aquat. Sci. 

37: 1184-1 192. 

Bjornn, T.C., M.A. Brusven, M.P. Molnau, J.H. 

Milligan, R.A. Klamt, E. Chacho, and C. Schaye. 

1977. Transport of granitic sediments in streams and 

its effects on insects and fish. For. Wildl. Range Exp. 

Stn., Compl. Rep. Water Resour. Res. Inst. Proj. 

B-036-IDA. University of Idaho, Moscow. 43 pp. 

Blum, J. P. 1984. Management strategies for restoration 

and rehabilitation of sockeye salmon (Oncorhynchus 

nerka) in Lake Ozette, Washington. Pages 55-62 in 

J.M. Walton and D. B. Houston, eds. Proceedings of 

the Olympia wild fish conference. Port Angeles, 

Wash. 

Bocking, R.C., and R.M. Peterman. 1988. Preseason 

forecasts of sockeye salmon (Oncorhynchus nerka): 

comparison of methods and economic considerations. 

Can. J. Fish. Aquat. Sci. 45:1346-1354. 

Brannon, E.L. 1965. The influence of physical factors 

on the dcvelopment and weight of sockeye salmon 
embryos and alevins. Int. Pac. Salmon Fish. Comm. fisheries. Ph.D. Thesis. University of Washington, 

Progr. Rep. No. 12. 26 pp. Seattle. 135 pp. 

Brannon, E.L. 1972. Mechanisms controlling migration 

of sockeye salmon fry. Int. Pac. Salmon Fish. Comm. 

Bull. 21:l-86. 

Brannon, E.L. 1982. Orientation mechanisms of homing 

salmonids. Pages 219-227 in E.L. Brannon and E.O. 

Salo, eds. Proceedings of the salmon and trout 

migratory behavior symposium. University of 

Washington Press, Seattle. 

Brett, J.R. 1952. Temperature tolerance in young 

Pacific salmon, genus Oncorhynchus. J. Fish. Res. 

Board Can. 9(6):265-323. 

Brett, J.R. 1964. The respiratory metabolism and swimming performance of young sockeye salmon. J. Fish. 

Res. Board Can. 21:1183-1226. 

Brett, J.R. 1970. Fish - the energy cost of living. Pages 

37-52 in WJ. McNeil, ed. Marine Aquaculture. 

Oregon State University Press, Corvallis. 

Brett, J.R. 1971. Energetic responses of salmon to temperature. A study of some thermal relations in the 

physiology and freshwater ecology of sockeye salmon 

(Oncorhynchus nerka). Am. Zoo1 .11(1):99-113. 

Brett, J.R., and J.M. Blackburn. 1981. Oxygen requirements for growth of young coho (Oncorhynchus 

kisutch) and sockeye (0. nerka) salmon at 15 "C. Can. 

J. Fish. Aquat. Sci. 38:399-404. 

Brett, J.R., and D.A. Higgs. 1970. Effect of temperature on the rate of gastric digestion in fingerling 

sockeye salmon (Oncorhynchus nerka). J. Fish. Res. 

Board Can. 27(7): 1967-1979. 

Brett, J.R., J.E. Shelbourn, and C.T. Shoop. 1969. 

Growth rate and body composition of fingerling 

sockeye salmon, Oncorhynchus nerka, in relation to 

temperature and ration size. J. Fish. Res. Board Can. 

26(9):2363-2394. 

Bryant, M.D. 1976. Lake Washington sockeye salmon: 

biological production, and a simulated harvest by three 

Bryant, M.D., and S.B. Mathews. 1973. The Lake 

Washington sockeye salmon sport fishery: catch, 

fishing effort, and economic evaluation, 1973. 

Special Report Fisheries Research Institute, University 

of Washington, Seattle. 18 pp. 

Burgner, R.L. 1958. A study of the fluctuations in abundance, growth, and survival in the early life stages of 

the red salmon (Oncorhynchus nerka Walbaum) of the 

Wood River lakes, Bristol Bay, Alaska. Ph.D. Thesis. 

University of Washington, Seattle. 200 pp. 

Burgner, R.L. 1980. Some features of the ocean migration and timing of Pacific salmon. Pages 153-164 in 

W.J. McNeil and D.C. Himsworth, eds. Symposium on 

salmonid ecosystems of the North Pacific. Oregon 

State University Press, Corvallis. 

Clark, C.W., and D.A. Levy. 1988. Die1 vertical migrations by juvenile sockeye salmon and the antipredation 

window. Am. Nat. 131:271-290. 

Clark, W.G. 1985. Fishing in a sea of court orders: 

Puget Sound salmon management 10 years after the 

Boldt Decision. N. Am. J. Fish. Manage. 5:417-434. 

Clarke, W.C., and H.D. Smith. 1972. Observations on 

the migration of sockeye salmon fry (Oncorhynchus 

nerka) in the lower Babine River. J. Fish. Res. Board 

Can. 29(1): 151-159. 

Cousens, N.F., G.A. Thomas, G.C. Swan, and M.C. 

Healey. 1982. A review of salmon escapement 

estimation techniques. Can. Tech. Rep. Fish. Aquat. 

Sci. No. 1108. 122 pp. 

Davidson, F.A. 1966. Population trends in the blueback 

and upper Columbia River fall chinook salmon. Public 

Utility District of Grant County. Ephrata, Wash. 36 pp. 

Davis, J.C. 1973. Sublethal effects of bleached Kraft 

pulpmill effluent on respiration and circulation in 

sockeye salmon (Oncorhynchus nerka). J. Fish. Res. 

Board Can. 30(2):369-377. 
Dell, M.B. 1963. Oceanic feeding habits of the sockeye 

salmon (Oncorhynchus nerka Walbaum), in Aleutian 

waters. M.A. Thesis. University of Michigan, Ann 

Arbor. 40 pp. 

Dlugokenski, C.E., W.H. Bradshaw, and S.R. Hager. 

1981. An investigation into the limiting factors to 

Lake Ozette sockeye salmon production and a plan for 

their restoration. U.S. Fish and Wildlife Service 

Report, Fisheries Assistance Olfice, Olympia. 51 pp. 

Doble, B.D., and D.M. Eggers. 1978. Die1 feeding 

chronology, rate of gastric evacuation, daily ration, and 

prey selectivity in Lake Washington juvenile sockeye 

salmon (Oncorhynchus nerka). Trans. Am. Fish. Soc. 

107(1):36-45. 

Donaldson, L.R., and E.J. Foster. 1941. Experimental 

study of the effect of various water temperatures on the 

growth, fwd utilization and morlality rates of 

fingerling sockeye salmon. Trans. Am. Fish. Soc. 

70:339-346. 

Eggers, D.M. 1977. The nature of prey selection by 

planktivorous fish. Ecology 58(1):46-59. 

Eggers, D.M. 1978. Limnetic feeding behavior of juvenile sockeye salmon in Lake Washington and predator 

avoidance. Limnol. Oceanogr. 23(6): 11 14-1125. 

Eggers, D.M. 1982. Planktivore preference by size. 

Ecology 63:381-390. 

Eggers, D.M., N.W. Bartoo, N.A. Rickard, R.E. Nelson, 

R.C. Wissmar, R.L. Burgner, and A.H. Devol. 1978. 

The Lake Washington ecosystem: the perspeclive 

from the fish community production and for age base. 

J. Fish. Res. Board Can. 35(5): 1553-1571. 

Foerster, R.E. 1925. The importance ol copepoda in the 

natural diet of sockeye salmon. Contrib. Can. Biol. 

2(16):2009-2016. 

Foerster, R.E. 1968. The sockeye salmon, Oncorhynchus nerka. Bull. Fish. Rcs. Board Can. 162. 422 pp. 

Foerster, R.E., and W.E. Ricker. 1941. The effect oC 

reduction of predaceous lish on survival of young 

sockeye salmon at Cultus Lake. J. Fish. Res. Board 

Can. 5(4):3 15-336. 

Foskett, D.R. 1956. Contributions to the life-history 

of the sockeye salmon. British Columbia Department 

of Fisheries Report Number 4 1. 

French, R.R., and W.B. McAlister. 1970. Winter distribution of salmon in relation to currents and water 

masses in the northeastern Pacific Ocean and 

migrations of sockeye salmon. Trans. Am. Fish. Soc. 

99(4):649-663. 

French, R., H. Bilton, M. Osako, and A. Hartt. 1976. 

Distribution and origin of sockeye salrnon 

(Oncorhynchus nerka) in offshore waters of the North 

Pacific Ocean. Int. North Pac. Fish. Comm. Bull. 34. 

113 pp. 

Furnell, D. J., and J. R. Brett. 1986. Model of monthly 

marine growth and natural mortality for Babine Lake 

sockeye salmon (Oncorhynchus nerka). Can. J. Fish. 

Aquat. Sci. 43(5):999- 1004. 

Ginetz, K.M., and P.A. Larkin. 1976. Factors affecting 

rainbow trout (Salmo gairdneri) predation on migrant 

fry of sockeye salmon. J. Fish. Res. Board Can. 

33(1): 19-24. 

Hart, J.L. 1973. Pacific fishes of Canada. Fish. Res. 

Board Can. Bull. 180. 665 pp. 

Hartt, A.C. 1980. Juvenile salmonids in the oceanic ecosystem: the critical first summer. Pages 25-57 in W.J. 

McNeil and D.C. Himsworth, eds. Symposium on 

salmonid ecosystems of the North Pacific. Oregon 

State University Press, Corvallis. 

Hyatt, K.D., and J.D. Stockner. 1985. Response of sockeye salmon (Oncorhynchus nerka) to fertilization of 

British Columbia coastal lakes. Can. J. Fish. Aquat. 

Sci. 42(2):320-331. 

Kolb, R. 1971. A review of Lake Washington sockeye 

(Oncorhynchus nerka) age and racial characteristics as 

determined by scale analysis. Wash. Dep. Fish. Suppl. 

Progr. Rep. 9 pp. 
LeBrasseur, R.J. 1966. Stomach contents of salmon 

and steelhead uout in the northeastern Pacific Ocean. 

J. Fish. Res. Board Can. 23(1):85-100. 

LeBrasseur, R.J., C.D. McAllister, W.E. Barraclough, 

O.D. Kennedy, J. Manzer, D. Robinson, and K. 

Stephens. 1978. Enhancement of sockeye salmon 

(Oncorhynchus nerka) by lake fertilization in Great 

Central Lake: summary report. J. Fish. Res. Board 

Can. 35: 1580-1596. 

Leggett, W.C. 1977. The ecology of fish migrations. 

Annu. Rev. Ecol. Syst. 8:285-308. 

Manzer, J.I. 1976. Distribution, food, and feeding of the 

threespine stickleback, Casterosteus aculeatus, in 

Great Central Lake, Vancouver Island, with comments 

on competition for food with juvenile sockeye salmon, 

Oncorhynchus nerka. U.S. Natl. Mar. Fish. Serv. Fish. 

Bull. 74(3):647-668. 

Manzer, J.I., and 1. Miki. 1986. Fecundity and egg retention of some sockeye salmon (Oncorhynchus nerka) 

stocks in British Columbia. Can. J. Fish. Aquat. Sci. 

43:1643-1655. 

Manzer, J.I., M. Wright, I. Miki, and K.D. Hyatt. 1984. 

Abundance, upstream migration, age-composition and 

fecundity of Hobiton Lake adult sockeye 

(Oncorhynchus nerka), 1982. Can. Tech. Rep. Fish. 

Aquat. Sci. 1262. 57 pp. 

Mathisen, O.A. 1955. Studies on the spawning biology 

of the red salmon, Oncorhynchus nerka Walbaum, in 

Bristol Bay, Alaska, with special reference to the effect 

of altered sex ratios. Ph.D. Thesis. University of 

Washington, Seattle. 285 pp. 

Mathisen, O.A., and H.D. Smith. 1982. Hydroacoustic 

assessment of juvenile sockeye salmon in Babine 

Lake, British Columbia in 1975. Can. Tech. Rep. Fish. 

Aquat. Sci. No. 1103. 13 pp. 

McCart, P. 1967. Behavior and ecology of sockeye salmon fry in the Babine River. J. Fish. Res. Board Can. 

24(2):375-428. 

McDonald, J.G. 1969. Distribution, growth, and survival 

of sockeye fry (Oncorhynchus nerka) produced in 

natural and artificial stream environments. J. Fish. 

Res. Board Can. 25(2):229-267. 

McDonald, J. 1973. Diel vertical movements and 

feeding habits of underyearling sockeye salmon 

(Oncorhynchus nerka) at Babine Lake, B.C. Fish. Res. 

Board Can. Tech. Rep. 378. 55 pp. 

Miller, RJ., and E.L. Brannon. 1982. The origin and 

development of life history patterns in Pacific 

salmonids. Pages 296-309 in E.L. Brannon and E. 0. 

Salo, eds. Proceedings of the salmon and trout 

migratory behavior symposium. University of 

Washington Press, Seattle. 

Mullan, J.W. 1986. Determinants of sockeye salmon 

abundance in the Columbia River, 1880's- 1982: 

review and synthesis. U.S. Fish Wildl. Serv. Biol. Rep. 

86(12). 136 pp. 

Narver, D.W. 1970. Diel vertical movements of underyearling sockeye salmon and the limnetic zooplankton 

in Babine Lake, British Columbia. J. Fish. Res. Board 

Can. 27(2):281-316. 

Northcote, T.G., and H.W. Lorz. 1966. Seasonal and die1 

changes in food of adult kokanee (Oncorhynchus 

nerka) in Nicola Lake, British Columbia. J. Fish. Res. 

Board Can. 23(6): 1259-1263. 

Olsen, J.C. 1968. Physical environment and egg development in a mainland beach area and an island beach 

area of Iliamna Lake. Univ. Wash. Publ. Fish. New 

Ser. 3:169-198. 

Pacific Fishery Management Council. 1983. Proposed 

plan for managing the 1983 salmon fisheries off the 

coasts of California, Oregon, and Washington. Pac. 

Fish. Manage. Counc., Portland, Oreg. 332 pp. 

Pella, J.J. 1968. Distribution and growth of sockeye 

salmon fry in Lake Aleknagik, Alaska, during the 

summer of 1962. Univ. Wash. Publ. Fish. New Ser. 

3:45-112. 

Peterman, R.M. 1984. Density-dependent growth in 

early ocean life of sockeye salmon (Oncorhynchus 

nerka). Can. J. Fish. Aquat. Sci. 4 l(12): 1825- 1829. 
Peterman, R.M. 1985. Patterns of interannual variation 

in age at maturity of sockeye salmon (Oncorhynchus 

nerka) in Alaska and British Columbia. Can. J. Fish. 

Aquat. Sci. 42(10): 1595-1607. 

Peven, C.M. 1987. Downstream migration timing of 

two stocks of sockeye salmon on the midColumbia 

River. Northwest Sci. 61:186-190. 

Poe, P.H., and O.A. Mathisen. 198 1. Distance from sea 

and elevation of important sockeye salmon spawning 

grounds. Fish. Res. Inst. Univ. Wash. Circ. 81-1. 

23 PP. 

Puget Sound Tribes, Northwest Indian Fisheries Commission, and Washington State Department of 

Fisheries. 1989. 1989 Puget Sound sockeye salmon 

forecasts and management recommendations. Joint 

Report, April 1989. Olympia. 29 pp. 

Quinn, T.P. 1982a. Intra-specific differences in sockeye 

salmon fry compass orientation mechanisms. Pages 

79-85 in E.L. Brannon and E.O. Salo, eds. 

Proceedings of the salmon and trout migratory 

behavior symposium. University of Washington Press, 

Seattle. 

Quinn, TS. 1982b. A model for salmon navigation on 

the high seas. Pages 229-237 in E.L. Brannon and E.O. 

Salo, eds. Proceedings of the salmon and trout 

migratory behavior symposium. University of 

Washington Press, Seattle. 

Quinn, T.P., and E.L. Brannon. 1982. The use of celestial and magnetic cues by orienting sockeye salmon 

smolts. J. Comp. Physiol. 147547-552. 

Rees, W.H. 1957. The vertical and horizontal distribution of seaward migrant salmon in the forebay of 

Baker Dam. Wash. Dep. Fish. Fish. Res. Pap. 

2(1):5-17. 

Reiser, D.W., and T.C. Bjornn. 1979. Habitat requirements of anadromous salmonids. U.S. For. Serv., Pac. 

Northwest For. Range Exp. Stn. Gen. Tech. Rep. 

PNW-96. 54 pp. 

Ricker, W.D. 1982. Size and age of British Columbia 

sockeye salmon (Oncorhynchus nerka) in relation to 

environmental factors and the fishery. Can. Tech. Rep. 

Fish. Aquat. Sci. 1115. 117 pp. 

Rogers, D. E. 1968. A comparison of the food of sockeye salmon fry and threespine sticklebacks in the 

Wood River Lakes. Univ. Wash. Publ. Fish. New Ser. 

3:l-44. 

Ruggerone, G.T., and D.E. Rogers. 1984. Arctic char 

predation on sockeye salmon smolts at little Togiak 

River, Alaska. U.S. Natl. Mar. Fish. Serv. Fish. Bull. 

82(2): 401-410. 

Scott, W.B., and E.J. Crossman. 1973. Freshwater fishes 

of Canada. Bull. Fish. Res. Board Can. 184. 966 pp. 

Stober, Q.J., and A.H. Hamalainen. 1979. Cedar River 

sockeye salmon fry emigration. Final report. 

University of Washington Fisheries Research Institute, 

Seattle. 52 pp. 

Stockner, J.G., and K.D. Hyatt. 1984. Lake fertilization: 

state of the art after 7 years of application. Can. Tech. 

Rep. Fish. Aquat. Sci. 1324. 33 pp. 

Stockner, J.G., and K.S. S hortreed. 1983. A comparative limnological survey of 19 sockeye salmon 

(Oncorhynchus nerka) nursery lakes in the Fraser 

River system, British Columbia. Can. Tech. Rep. Fish. 

Aquat. Sci. 1190. 63 pp. 

Tarzwell, C.M. 1957. Water quality criteria for aquatic 

life. Pages 246-272 in Biological problems in water 

pollution. U.S. Dep. Health Educ. Welfare, R.A. Taft 

San. Eng. Cent., Cinncinati, Ohio. 

Thompson, R. B., and D. F. Tufts. 1967. Predation by 

Dolly Varden and northern squawfish on 

hatchery-reared sockeye salmon in Lake Wenatchee, 

Washington. Trans. Am. Fish. Soc. 96(4): 424-427. 

Thorne, R.E. 1979. Hydroacoustic estimates of adult 

sockeye salmon (Oncorhynchus nerka) in Lake 

Washington, 1972-75. J. Fish. Res. Board Can. 

36(9): 1145-1149. 

Thorne, R.E., and J.J. Ames. 1987. A note on variability 

of marine survival of sockeye salmon (Oncorhynchus 
nerka) and effecls of flooding on spawning success. 

Can. J. Fish. Aquat. Sci. 44:1791-1795. 

Wahle, R.J., R.O. Koski, and R.Z. Smith. 1979. Contribution of 1960-63 brood hatchery-reared sockeye 

salmon, Oncorhynchus nerka, to the Columbia River 

commercial fishery. U.S. Natl. Mar. Fish. Serv. Fish. 

Bull. 77(1): 229-242. 

Ward, F.J., and P.A. Larkin. 1964. Cyclic dominance 

in Adams River sockeye salmon. Int. Pac. Salmon 

Fish. Comm. Prog. Rep. No. 11. 11 3 pp. 

Wedemeyer, G.A., R.L. Saunders, and W.C. Clarke. 

1980. Environmental factors affecting smoltification 

and early marine survival of anadromous salmonids. 

Mar. Fish. Rev. 42(1): 1-14. 

West, C.J., and P.A. Larkin. 1986. Evidence for sizeselective mortality of juvenile sockeye salmon 

(Oncorhynchus nerka) in Babine Lake, British 

Columbia. Can. J. Fish. Aquat. Sci. 44:712-721. 

Woodey, J.C. 1972. Distribution, feeding, and growth 

of juvenile sockeye salmon in Lake Washington. 

Ph.D. Thesis. University of Washington, Seattle. 

99 PP. 

Wydoski, R.S., and D.H. Bennett. 1981. Forage species 

in lakes and reservoirs of the Western United States. 

Trans. Am. Fish. Soc. 110(6):764-771. 

Wydoski, R.S., and R.R. Whitney. 1979. Inland fishes 

of Washington. University of Washington Press, 

Seattle. 168 pp. 
1 aid Invertebrates (Pacific Northwest)--Sockeye Salmon I 

PACE 1 Biological Report 82(11.116)* 1 4. Title and Subtitle 

Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes 

5. Report Date 

December 1989 

7. Author(a) 

Gilbert B. Pauley, Ron Risher, and Gary L. Thomas 

9. Performing Orpsnizatlon Name 811d Addreas 

Washington Cooperative Fishery Research Unit 

University of Washington 

Seattle, WA 98195 

U.S. Department of the Interior U.S. Army Corps of Engineers 

Fish and Wildlife Service Waterways Experiment Station 

National Wetlands Research Center P.O. Box 631 

Washington, DC 20240 Vicksburg, MS 39 180 

"-

8. Perlorming Organization Rept. No. 

10. Projectfraskmork Unit No. 

11. Contnct(c) or Gnnt(G) No. 

(C) 

(G) 

I 

1 ir Suppiemantsy Nor I 

12. Sponsoring Organiz~tion Name and Address 

*U.S. Army Corps of Engineers Report No. TR EL-82-4. 

16. Abatract (Limit: 200 words) 

13.Type of Report 6 Period Covered 

Species profiles are literature summaries of the taxonomy, morphology, range, life history, and environmental 

requirements of coastal aquatic species. They are designed to assist in environmental impact assessment. 

Sockeye salmon always spawn in a lake associated with a river or in the outlet river. The young fish use the 

lakes for rearing. The brilliant red flesh is highly prized by commercial and sport fishermen. Washington 

State and the Columbia River are the southern limit of reproducing populations of sockeye salmon. Sockeye 

salmon are primarily plankton feeders. They appear to thrive best at temperatures of 10-15 'C. Ocean 

distribution does not appear to be limited by salinity. Adults require gravel with adequate water circulation 

for successful spawning and egg hatching. 

17. Document Analysim 8. Descriptors 

Estuaries Temperature Oxygen competition 

Feeding habits Suspended sediments Fisheries 

Growth Salmon Sediments 

Unlimited distribution 

b. IdentilierdOpen-Ended Term 

Sockeye salmon Life history Predators 

Oncorhynchus nerka Competitors Salinity requirements 

Spawning 

Temperature requirements 

c. COSATl FieldlGroup 

L I I I 

(See ANSI-239.18) OPTIONAL FORM 272 (4-77) 

(Formerly NTIS-35) 

a. NO. of ~lg~. 

vii + 22 

18. Availability Statement 

ZU Se~urIly CI.88 (This Pwe) 

Unclassified 

~e~artment of commerce 

1B.Security CIsu (Thn Report) 

Unclassified 

Z. PIicC 
As the Nation's principal conservation agency, the Department of 

the Interior has responsibility for most of our nationally owned 

public lands and natural resources. This includes fostering the 

wisest use of our land and water resources, protecting our fish 

and wildlife, preserving the environmental and cultural values of our 

national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department assesses 

our energy and mineral resources and works to assure that their 

development is in the best interests of all our people. The Department also has a major responsibility for American Indian reservation 

communities and for people who live in island territories under U.S. 

administration. 

U.S. DEPARTMENT OF THE INTERIOR 

FlSH AND WILDLIFE SERVICE 

TAKE PRIDE 

in America 

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