QL

155

.S63

no.82-

11.86

Biological Report 82(11.86)

January 1989

Library

Na!?onal Wetlands Research Ct?nter

U. S. FIsC and Wifdllfc Service

700 Cafutzdome Doufcvard

I.*P.at* I 9 7wd-m

TR EL-82-4

Species Profiles: Life Histories and

Environmental Requirements of Coastal Fishes

and Invertebrates (Pacific Northwest)

SEA-RUN CUTTHROAT TROUT

Fish and Wildlife Service

U.S. Department of the Interior

Coastal Ecology Group

Waterways Experiment Station

U.S. Army Corps of Engineers

Biological Report 82(11.86)

TR EL-82-4

January 1989

Species Profiles: Life Histories and Environmental Requirements

of Coastal Fishes and Invertebrates (Pacific Northwest)

SEA-RUN CUTTHROAT TROUT

Gilbert B. Pauley, Kevin Oshima, Karen L. Bowers, and G. L. Thomas

Washington Cooperative Fishery Research Unit

School of Fisheries

University 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

This study was conducted

in cooperation with

Coastal Ecology Group

Waterways Experiment Station

U.S. Army Corps of Engineers

Vicksburg, MS 39180

Performed for

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 coastfi 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., K. Oshima, K.L. Bowers, and G.L. Thomas. 1989. Species profiles:

life histories and environmental requirements of coastal fishes and

invertebrates (Pacific Northwest)--sea-run cutthroat trout. U.S. Fish Wild.

Serv. Biol. Rep. 82(11.86). U.S. Army Corps of Engineers TR EL-82-4. 21 PP.
PREFACE

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, environmental

requirements, 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

National Wetlands Research Center

U.S. Fish and Wildlife Service

NASA-Slide11 Computer Complex

1010 Gause Boulevard

Slidell, LA 70458

or

U.S. Army Engineer Waterways Experiment Statior

Attention: WESER-C

Post Office Box 631

Vicksburg, MS 39180

iii
CONVERSION TABLE

Multiply !J! To Obtain

millimeters (mm) 0.03937 inches

centimeters (cm) 0.3937 inches

meters (m) 3.281 feet

meters (m) 0.5468 fathoms

kilometers (km) 0.6214 statute miles

kilometers (km) 0.5396 nautical miles

square meters (m*) 10.76 square feet

square kilometers (km*) 0.3861 square miles

hectares (ha) 2.471 acres

liters (1)

cubic meters (m3)

cubic meters (m3)

milligrams (mg)

grams (9)

kilograms (kg)

metric tons (t)

metric tons (t)

0.2642 gallons

35.31 cubic feet

0.0008110 acre-feet

0.00003527 ounces

0.03527 ounces

2.205 pounds

2205.0 pounds

1.102 short tons

kilocalories (kcal) 3.968 British thermal units

Celsius degrees ("C) 1.8('C) + 32 Fahrenheit degrees

U.S. Customary to Metric

inches 25.40 millimeters

inches 2.54 centimeters

feet (ft) 0.3048 meters

fathoms 1.829 meters

statute miles (mi) 1.609 kilometers

nautical miles (nmi) 1.852 kilometers

square feet (ft*) 0.0929 square meters

square miles (mi*) 2.590 square kilometers

acres 0.4047 hectares

gallons (gal) 3.785 liters

cubic feet (ft3) 0.02831 cubic meters

acre-feet 1233.0 cubic meters

ounces (oz)

ounces (oz)

pounds (lb)

pounds (lb)

short tons (ton)

British thermal units (Btu)

Fahrenheit degrees (OF)

28350.0

28.35

0.4536

0.00045

0.9072

0.2520

0.5556 (OF

iv

milligrams

grams

kilograms

metric tons

metric tons

32)

kilocalories

Celsius degrees

Metric to U.S. Customary
CONTENTS

Page

PREFACE ............

CONVERSION TABLE. .......

ACKNOWLEDGMENTS ........

NOMENCLATURE/TAXONOMY/RANGE . . ...................... 1

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

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

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

Spawning . . , . . . . . . ...................... 4

Eggs and Fecundity . . . . ...................... 6

Alevins and Fry. . . . . . ...................... 6

Juveniles and Smolting . . ...................... 6

Saltwater Life . . . . . . ...................... 7

AGE AND GROWTH CHARACTERISTICS. ...................... 7

ECOLOGICAL ROLE . . . . . . . . ...................... 8

ENVIRONMENTAL REQUIREMENTS. . . ....................... 9

Temperature. . . . . . . . ...................... 9

Substrate and Cover. . . . ...................... 10

Dissolved Oxygen . . . . . ...................... 11

Turbidity. . . . . . . . . ...................... 11

Water Velocity . . . . . . ...................... 11

Water Depth. . . . . . . . ...................... 12

Timber Harvest . . . . . . ...................... 12

THE FISHERY . . . . . . . . . . ...................... 12

LITERATURE CITED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

......................

......................

......................

iii

iv

vi
ACKNOWLEDGMENTS

The authors thank James Johnston of the Washington Department of Game and Howard

Fuss of the Washington Department of Fisheries for their reviews and technical

suggestions.

vi
Figure 1. Sea-run cutthroat trout.

SEA-RUN CUTTHROAT TROUT

NOMENCLATURE/TAXONOMY/RANGE

Scientific name.. ..Salmo clarki clarki

Preferred common name...mun

throat trout (Figure 1)

Other common names....Coastal cutthroat trout, red-throated trout,

sea trout, sea-run cutthroat, searun cut, blueback trout, autumn

trout, harvest trout, yellowbelly.

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

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

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

Geographic range: In coastal streams

from northern California through

Oregon and British Columbia and into

southeastern Alaska (Figures 2 and

3). Rarely found more than 160 km

inland.

MORPHOLOGY/IDENTIFICATION AIDS

The following information is taken

from Hart (1973), Scott and Crossman

(1973), and Wydoski and Whitney

(1978). Morphological differences

between coastal cutthroat and inland

cutthroat were outlined by Qadri

(1959)and Trotter (1987).

Morphology: Fin rays--dorsal fin

8-11, anal 8-12, pectorals 13, and

pelvic 9. Adipose, small, fleshy and

slender, pelvics abdominal in position

with a free-tipped fleshy appendage

above insertion. Cycloid scales, 120-

180 at lateral line; gill rakers 15-

22, rough and widely spaced on first

gill arch. Body elongate, slightly

compressed.

Identification aids: Red or orange

streak along the inner edge of lower

jaw in fresh specimens. Small teeth

at the back of the tongue between the

second gill clefts. Teeth well

developed on upper and lower jaws.

Maxillary usually extends beyond the

posterior margin of the eye in fish

longer than 10 cm. Back is greenishblue tending toward metallic blue in

fresh sea-run fish; sides silvery;

distinct black spots on back, head,

1
CANADA

(South Fork)

WASHINGTON

OREGON

Figure 2. Map showing major rivers that support sea-run cutthroat trout in the

Pacific Northwest. It should be noted that many small streams too numerous to

be shown on this map also support sea-run cutthroats. An active sport fishery

2
OREGON

MILES

O>

0 50 100

’ 8. KILOMETERS

exists for these fish in saltwater throughout Puget Sound and Hood Canal as well

as in the rivers.

3
ALASKA \

\

- -

---_ \

UNITED STATES .-\,

Figure 3. Sea-run cutthroat trout coastal distribution from northern California

to southeastern Alaska and the general limits of inland distribution in North

America (after Johnston and Mercer 1976).

anal fin, tail, and sides (extending

well below lateral line). Size range

of adults is 0.5 to 2.7 kg.

REASON FOR INCLUSION IN SERIES

Although not quite as well-known as

its larger cousin the steelhead (Salmo

gairdneri), the sea-run cutthroat

trout is extensively sought by anglers

through the rivers and small streams

of Northern California, Oregon,

Washington, and British Columbia that

flow into saltwater. The freshwater

sport fishery takes place in the fall,

while an extensive saltwater sport

fishery exists year round in inland

waters such as Puget Sound. The searun cutthroat is highly sought after

by fly-fishermen.

LIFE HISTORY

Spawning

Sea-run cutthroat trout have a variable life history, which will be discussed below. Like salmon, sexually

4
“W

.

mature sea-run cutthroat trout return

to their natal streams to spawn.

Spawning sea-run cutthroat trout home

precisely to specific tributaries,

while immature fish do not always

return to their home stream to feed or

when seeking an overwinter habitat

(Johnston 1982). Homing of native

sea-run cutthroat is extremely precise

(Campton 1980), although hatcheryplanted fish may stray as much as 30%,

which makes survival rates impossible

to determine (Johnston and Mercer

1976). Gel electrophoretic studies

have shown that cutthroat populations

are genetically discrete at the small

stream level (Campton 1980), although

there is limited hybridization with

hatchery-propagated steelhead trout

(Campton and Utter 1985).

The time of return to freshwater for

spawning is fairly consistent among

cutthroat trout from the same stream,

but varies widely by geographical

location (Johnston and Mercer 1976;

Johnston 1982). In Oregon and

Washington, cutthroat trout re-enter

freshwater anytime from July through

March (Sumner 1952; Anderson and

Narver 1975). Very few overwinter in

saltwater (Johnston 1982). A spring

run has been observed only in Alaska

(Jones 1972). In addition, a small

percentage of the immigrants are sexually immature individuals (Jones

1973-76; Johnston 1982; Tipping 1986).

In most coastal rivers of Washington

and Oregon, the stocks of fish are

sexually mature at first return to

freshwater; however, a large percentage of cutthroat females in the

Columbia River, Puget Sound, British

Columbia, and Alaska do not spawn

during the winter of their first

return to freshwater (Johnston 1982).

Anadromous cutthroat trout travel

farther upstream toward the headwaters

of the watershed than either steelhead

trout or coho salmon and rear sympatrically with resident cutthroat populations (Johnston 1982; Michael 1983).

Spawning generally takes place in

late winter and spring, but timing

varies by geographic location (Dymond

1932; Cramer 1940; Scott and Crossman

1973). In Puget Sound and southern

British Columbia, coastal cutthroat

trout exhibit two distinct migration

times: (1) fish returning to large

river systems begin entering in July

and peak in September-October (early

entry fish) and (2) fish returning to

small streams draining directly to

saltwater begin entering in November

and peak in January-February (late

entry fish) (Johnson 1982; Mercer

1982). This difference is most likely

due to food availability, saltwater

tolerance, or stream flows (Johnston

1982). Throughout their range, searun cutthroat trout spawn in small

tributaries of large or small streams

with a drainage area less than 13 km

and may thereby avoid competition for

rearing area with steelhead (sea-run

rainbow trout,

coho

Salmo gairdneri) and

salmon (Oncorhynchus klsutch)

(Cramer 1940; Sumner 1952; Dewitt

1954; Glova and Mason 1977; Johnston

1982). Cutthroat trout prefer

spawning habitat with small-tomoderate-size gravel (Hunter 1973).

Spawning behavior in cutthroat trout

is typical of other stream-spawning

salmonids such as steelhead and salmon

(Smith 1941; Cope 1957; Scott and

Crossman 1973). The female digs a

redd in the gravel and deposits her

eggs. Simultaneously, the male covers

the eggs with milt. The female then

buries the eggs under a layer of

gravel. Although cutthroat trout are

repeat spawners, post-spawning mortalities are sometimes high due to

weight loss and the rigors of spawning

(Cramer 1940; Sumner 1952; Giger 1972;

Scott and Crossman 1973). The fish

that survive migrate downstream in

early to late spring. Kelts (spent

adults) enter saltwater earlier than

smolting juveniles (Giger 1972; Jones

1975). Sumner (1952) stated that 39%

of the cutthroat survived the first

spawning in Oregon, 17% the second,

and 12% the third. These data are

representative of conditions where a

targeted cutthroat fishery does not

5
exist. Sportfishing pressure reduces

the survival of spawning adults

following the first migration (Giger

1972).

Eggs and Fecundity

The spherical eggs of cutthroat

trout range in size from 4.3 to 5.1 mm

in diameter. Fecundity depends on the

size and age of the female. In

Alaska, fish ranging in size from 34

to 46 cm produced 486 to 2,286 eggs

per female (Jones 1975). In

Washington, females ranging from 20 to

43 cm produced 226 to 4,420 eggs

(Johnston and Mercer 1976). Average

number of eggs was between 1,100 and

1,700 for females of all sizes pooled

(Scott and Crossman 1973). Mercer

(1982) showed a strong linear correlation between increased length and

increased number of eggs, with an

"r" value of .97. Eggs normally hatch

in 28 to 40 days, but may require 50

days or more (Merriman 1935; Cope

1957; Scott and Crossman 1973).

Hatching is temperature-dependent

(Merriman 1935).

Alevins and Fry

Newly hatched yolk-sac larvae,

called alevins, remain in the gravel

in the redd for 1 to 2 weeks before

they emerge as fry. The fry are less

than 3 cm long and commonly live in

the shallow, low-velocity stream

margins (Johnston and Mercer 1976).

However, their distribution is often

governed by the presence of other salmonid species (see Ecological Role

section). The first scales are formed

when the fish are 3.5 cm in fork

length (FL)--a length normally

attained during the first summer of

life (Cooper 1970; Giger 1972).

The fry are sensitive to many kinds

of environmental changes. Logging

(Moring and Lantz 1974), increased

temperatures (Golden 1975), loss of

cover (Lowery 1965), reductions in

food supply, and siltation (Bustard

and Narver 1975) can all increase

larval mortality. Johnston and Mercer

(1976) listed a number of natural

sources of mortality, such as interspecific competition with other

salmonids, intraspecific competition,

and crowding induced by low summer

flows, but they indicated that habitat

alteration was probably the greatest

threat to cutthroat trout stocks.

Juveniles and Smolting

Prior to smolting and entering saltwater, juveniles (Parr) may migrate

up- and downstream several times

(Sumner 1953; Moring and Lantz 1975).

This migration can result in confusion

for someone trying to count or estimate the number of smolting cutthroat

trout migrating downstream and out

into the marine environment. The age

at which smolting first occurs is

extremely variable, being somewhat

size-dependent and occurring between

Age I and Age IV (Moring and Lantz

1975) or even later (Johnston and

Mercer 1976; Jones 1977; Fuss 1978).

A good working average is between Ages

III and IV. Fuss (1978, 1982) noted

that most initial migrants are Aged

III or IV and outlined several reasons why initial migration occurs at

different ages. Fish in these age

groups average 20-25 cm FL. In Washington and Oregon, downstream movement

of smolts takes place from March to

June, but peaks in mid-May (Johnston

and Mercer 1976).

A division of migration types seems

to exist between cutthroat trout

entering the protected water of areas

such as Puget Sound and those entering

areas of surf-pounded coast. Cutthroat trout entering protected waters

are, on average, younger and smaller

(Age II, 16 cm FL) (Michael 1983;

Johnston 1980), while those entering

surf zones are, on average, Age IV and

21 cm (Fuss 1982). Regardless of age

or habitat, cutthroat trout school

before entering the marine environment

and remain schooled throughout their

saltwater migrations (Giger 1972)--a

6
behavior which probably has survival

value.

Saltwater Life

Although there have been few studies

of cutthroat trout movements at sea,

it appears that they overwinter in the

marine environment and stay close to

shore. Although cutthroat remain at

sea varying lengths of time, they return to freshwater in the same year in

which they migrated out to sea (Giger

1972; Anderson and Narver 1975; Jones

1976; Johnston and Mercer 1976).

In Puget Sound, Washington, the

anadromous cutthroat trout feed and

migrate along the beaches, mostly in

water less than 3-m deep (Johnston

1980). In general, their movement

along the coast is believed to be correlated with onshore ocean currents,

with the fish staying close to the

coastline (Giger 1972; Johnston and

Mercer 1976). Regardless of age, anadromous cutthroat trout are believed to

begin schooling just before they enter

into the marine habitat (Johnston

1980). In Alaska, cutthroat trout were

reluctant to cross bodies of water 3

to 8 km wide, and preferred to follow

the shoreline (Jones 1976).

Many cutthroat trout have been

captured with scars from predator

attack while at sea, and that

predation is believed to represent a

major source of marine mortality

(Giger 1972). Estimates from Oregon

studies indicate 20%-40% survival of

initial migrant fish in the marine

environment (Giger 1972). Tipping

(1986) noted that survival was

considerably higher for hatchery searun cutthroat trout that were released

as smolts >21 cm FL (12.8% returns)

than for fish less than that length

(2.3% returns).

AGE AND GROWTH CHARACTERISTICS

Growth in cutthroat trout varies

according to the type of freshwater

and saltwater environments they

inhabit. Johnston and Mercer (1976)

summarized growth of adult cutthroat

trout in the Pacific Northwest

(Oregon, British Columbia, and Alaska)

and stated that fish that live in the

lower stream grow more rapidly than

fish that reside upstream and that

basic stream productivity also

influences growth. Nickelson and

Larson (1974) indicated that coastal

cutthroat trout not only lost weight

when food in streams was scarce, but

that they also decreased in length.

It is not known how frequently this

occurs.

Giger (1972) cited problems that

were inherent in determining cutthroat

trout age and growth due to variable

life cycles and different migration

strategies. An unusual pattern of

age-length distributions exists for

initial outmigrants because the fish

which spend more time in streams prior

to outmigration grow slower. This

slower growth may be a result of the

greater competition for food in

streams than occurs in the marine

environment. The result is that fish

from the same system entering

saltwater for the first time at Age IV

are only slightly larger than initial

outmigrants of Age II, and are much

smaller than Age IV fish that have

spent one or more summers at sea.

Fuss (1978) indicated that backcalculated lengths for young fish

(less than 2 years old) may be in

error, but the calculations for fish 2

years old or older are probably

accurate because of the near linear

relationship between fish length and

scale radius for the older fish.

According to Fuss (1978), Age I+

cutthroat ranged from 69 to 121 mm and

Age II+ cutthroat from 140 to 180 mm.

These figures may be misleading

because of the additional (+) growth.

In a subsequent paper, Fuss (1982)

indicated more accurately that Age I

fish were 70-77 mm and Age II fish

were loo-113 mm. The later work

involved more data and better

techniques. The growth rate in more

7
northern streams is slower than in the

more southern streams (Johnston and

Mercer 1976).

Cutthroat trout can live a maximum

of 10 years (Jones 1976), but most

adult fish runs are made up of

individuals between 3 and 6 years of

age (Johnston and Mercer 1976; Fuss

1982). Repeat spawners returning for

a fourth or fifth spawning attain

lengths of 17 to 19 inches (Giger

1972; Johnston and Mercer 1976).

ECOLOGICAL ROLE

The use of isolated headwater

streams by cutthroat trout for

spawning and the first years of

rearing serves to reduce hybridization

interactions with other salmonids,

primarily steelhead trout and coho

salmon, which typically spawn and rear

further downstream from nursing zones

of young-of-the-year and Age I

cutthroat trout (Johnston 1982).

Hybridization between cutthroat trout

and hatchery rainbow trout does not

occur in the few areas of overlap

(Sumner 1972; Campton 1980; Campton

and Utter 1985). Sympatric and allopatric populations of resident and

anadromous cutthroat trout may also

live within a watershed (Dewitt 1954;

Royal 1972; Scott and Crossman 1973;

Moring and Lantz 1975; Jones 1979;

Johnston 1982). Another selective

advantage for isolation of coastal

cutthroat trout, according to Johnston

(1982)s is in the outcome of social

interactions with anadromous steelhead

trout and coho salmon. Competitive

interactions for food and space between anadromous cutthroat trout and

steelhead trout or coho salmon

juveniles are most frequently decided

in favor of the steelhead trout or the

coho salmon (Glova and Mason 1976,

1977; Johnston 1982; Glova 1984).

Coastal cutthroat trout in British

Columbia also have evolved both a

spatial and feeding segregation where

they cohabit with the predacious Dolly

Varden (Salvelinus malma) (Andrusak

and Northcote 1971; Schultz and

Northcote 1972).

Habitat selection by juvenile cutthroat trout appears to be governed

by the presence of other salmonid

species. In the absence of competing

species, cutthroat trout have been

found to prefer pools (Glova and Mason

1976; Johnston and Mercer 1976; Glova

1984). When sympatric with coho

salmon, social dominance is asserted

by the coho salmon due to their

earlier emergence and larger body size

(Glova and Mason 1976; Johnston 1982).

Cutthroat and rainbow trout coexist

in the same reaches of many streams

(Moring and Youker 1979; Nicholas

1978), and occasionally they hybridize

(Campton and Utter 1985). The upper

reaches of the stream are usually

dominated by cutthroat trout, while

rainbow trout dominate the lower

sections (Hartman and Gill 1968;

Nicholas 1978). In areas where

anadromous rainbow trout (steelhead)

exist, this arrangement does not

always occur because the steelhead

juveniles emigrate at Age I and Age II

in the spring, which leaves available

the pools that the older cutthroat

trout seem to prefer in all sections

of the streams (Johnston and Mercer

1976). It has been pointed out that

there are three distinct life history

types of coastal cutthroat trout:

only one of these is anadromous, while

the other two types spend their entire

lives in freshwater (Thomasson 1978;

Michael 1983; Fuss 1982, 1984).

The result of interaction with

either coho salmon or rainbow trout

tends to be the displacement of the

juvenile young-of-the-year cutthroat

trout from the preferred pools to the

riffles. The cutthroat trout

generally return to the pools after

falling water temperatures reduce

aggressive interaction with these

other species and the heavier winter

flows threaten displacement from the

riffles (Bustard and Narver 1975;

Glova and Mason 1976).

8
k

“w

i

Cutthroat trout are opportunistic

feeders (Behnke and Zarn 1976; Wydoski

and Whitney 1978). Aquatic insects,

generally the most available food in

streams, are the dominant item in most

cutthroat trout diets (Dimick and Mote

1934; Lowery 1966; Allen 1969;

Carlander 1969; Baxter and Simon 1970;

Scott and Crossman 1973; Hunter 1973;

Griffith 1975; Glova 1984). Other

foods, such as zooplankton (McAfee

1966; Carlander 1969; Trojnar and

Behnke 1974; Hickman 1977),

terrestrial insects (Lowry 1966; Glova

1984; Martin 1984), and fish

(Carlander 1969; Hunter 1973; Martin

1984) are important locally or

seasonally. Many of the coastal

cutthroat stocks time their runs to

coincide with the availability of

salmon eggs in the streams (Johnston

1982).

Cutthroat trout become more

piscivorous as they increase in size

(Idyll 1942; McAfee 1966; Carlander

1969; Baxter and Simon 1970; Wydoski

and Whitney 1978). In freshwater,

cutthroat trout prey on threespine

stickleback (Gasterosteus aculeatus),

sockeye salmon (Oncorhynchus nerka),

and coho salmon (Lowery 1966;

Armstrong 1971). There is- considerable similarity and overlap in the

diet of young cutthroat trout and

young coho salmon, but direct conflict

may be avoided by habitat partitioning

(Glova 1984). Wilzbach (1985) indicated that food availability is rather

important in determining abundance and

microhabitat distribution of adult

cutthroat trout within a stream.

Freshwater predators of cutthroat

fry include rainbow trout, brook trout

(Sslvelinus fontinalis), Dolly Varden,

and shorthead sculpins (Cottus

confusus), as well as adult cutthroat

trout (Horner and Bjornn 1976). Other

possible predators are great blue

herons (Ardea herodias), belted

kingfishers (Ceryle alcyon), and mink

(Mustela vison) according to Horner

and Bjornn (1976).

In the marine environment, cutthroat

trout feed on gammarid amphipods,

sphaeromid isopods, callianassid

shrimp, immature crabs, and various

fish, including chum salmon

(Oncorhynchus keta), pink salmon

(Oncorhynchus gorbuscha), and Pacific

sand lance (Ammodytes hexapterus)

(Armstrong 1971; Simenstad and Kinney

1978); herring and sculpins are also

eaten.

Predators of sea-run cutthroat trout

in the marine environment include

Pacific hake (Merluccius productus),

spiny dogfish (Squalus acanthias),

harbor seal (Phoca vitalina), and

adult salmon (Gim977

ENVIRONMENTAL REQUIREMENTS

Temperature

Unusual stream temperatures can lead

to disease outbreaks in migrating

fish, altered timing of migration, and

accelerated or retarded maturation

(Reiser and Bjornn 1979). Most stocks

of anadromous salmonids have evolved

to take advantage of temperature

patterns in their home streams, and

significant abrupt deviations from the

normal pattern can adversely affect

their survival.

Cutthroat trout are not usually

found in waters where the maximum

temperature consistently exceeds 22

OC, although they tolerate brief

periods of daytime water temperatures

as high as 26 OC if considerable

cooling takes place at night (Behnke

and Zarn 1976). Bell (1973) reported

preferred temperatures of 9 to 12 OC

for cutthroat trout, with spawning

temperatures for cutthroat trout that

range from 6 to 17 OC (Hunter 1973).

The duration of egg incubation

varies and is dependent upon temperature (Merriman 1935); the optimum

temperature for incubation is approximately 10 to 11 OC (Merriman 1935;

Snyder and Tanner 1960). Egg survival

9
60009

0 POPULATION

CONSUMPTION

m TOTAL STOCK

BIOMASS

0 WATER

TEMPERATURE

o! . . . 1 . . . .

40

FEB MAR APR MAY JUN JUL AUG SEP OCT NOV

DATE

Figure 4. Sea-run cutthroat trout population consumption and total stock biomass

(wet weight) versus temperature in a 500-m long section of Bear Creek, Washington

(modified from Martin 1984).

also dependent

;zmith et al. 1983).

upon temperature

Metabolic rates of juvenile cutthroat trout are highest between 11

and 21 OC (Dwyer and Kramer 1975).

According to Martin (1984), stock

biomass remained nearly constant in a

given section of a small stream in the

Pacific Northwest from July to

September, but the water temperature

rose and food consumption increased

parallel to this rise (Figure 4). The

optimal temperature for juveniles is

15 OC, and equilibrium and ability to

swim is lost between 28 and 30 OC

In a study in southeast Alaska, outmigration of cutthroat trout peaked at

water temperatures between 4 to 6 OC

and inmigration began at 10 to 12 OC

and peaked at 9 to 10 OC (Jones 1977).

Substrate and Cover

(Heath 1963).

There is considerable variation in

suitable substrate size (gravel

diameter) for cutthroat trout; they

have been observed spawning in gravel

of 2 to 5 cm (June 1981), 0.6 to 10.2

cm (Hunter 1973), and 0.16 to 0.64

(Hooper 1973). Hanson (1977) found

to 4-year-old cutthroat trout.

streams associated with substrates

10

cm

lin

of
5 to 30 cm. Irving and Bjornn (1984)

found that survival of cutthroat

embryos increased as the percentage of

fine sediments decreased. The size of

adult cutthroat trout affects gravelsize selection and the tails of pools

in small tributary streams are usually

chosen for spawning (Johnston and

Mercer 1976).

Cover for fish can be provided by

overhanging vegetation, undercut

banks, and submerged objects such as

logs and rocks, as well as by water

depth and turbulence (Giger 1972;

Bustard and Narver 1975; Reiser and

Bjornn 1979). Cover protects the fish

from disturbance and predation and

also provides shade. The biomass of

cutthroat trout in streams increases

with the amount of cover present

(Wesche 1974; Lantz 1976; Nickelson

and Reisenbichler 1977).

Dissolved Oxygen

Doudoroff and Shumway (1970)

reported that salmonids that hatched

at low dissolved-oxygen levels tended

to be weak and small, to develop

slowly, and to show increased abnormalities. Cutthroat trout generally

avoid water with less than 5 mg/l of

dissolved oxygen ’ the summer

(Trojnar 1972; ienkulich 1974).

Doudoroff and Shumway (1970) also

demonstrated that both swimming speed

and growth rates of salmonids declined

as dissolved-oxygen levels decreased.

Turbidity

According to Reiser and Bjornn

(1979), salmonid fishes cease movement

or migration in streams with very high

silt loads (>4,000 mg/l). Because

more radiation is absorbed by turbid

water than by clear water, a thermal

barrier to movement and migration may

develop (Reiser and Bjornn 1979).

Bachman (1958) reported that cutthroat

trout adults stopped feeding and moved

to cover at turbidities above 35 ppm.

Suspended sediment levels exceeding

103 ppm, combined with dissolved

oxygen concentrations less than 6.9

mg/l and velocities in the redd of

less than 55 cm/h, can reduce egg

survival to below 10% (Bianchi 1963).

Fry emergence from the gravel may be

hindered by excessive sand and silt

(Reiser and Bjornn 1979). These

conditions may also limit the

production of benthic invertebrates

necessary for optimum rearing of

juvenile fish (Reiser and Bjornn

1979).

Water Velocity

Fry in stream environments prefer

shallower water and slower velocities

than other cutthroat trout life stages

(Miller 1957; Horner and Bjornn 1976).

Velocities of less than 0.30 m/s are

preferred and the optimum is less than

0.08 m/s (Horner and Bjornn 1976).

Juvenile cutthroat trout in streams

are most often found in velocities of

0.25 to 0.50 m/s (T.E. Nickelson,

unpubl. data). Thompson (1972) found

young-of-the-year and l-year-old cutthroat trout in water velocities of

0.5 to 0.6 m/s. Hanson (1977) found

l-year-old fish in velocities averaging 0.10 m/s. Hanson (1977) also

found 2-, 3-, and 4-year-old cutthroat

trout at mean velocities of 0.14,

0.20, and 0.14 m/s, respectively.

Cutthroat trout have been found

spawning in small streams with flow

rates as low as 0.01-0.03 m3/s (Dimick

and Marryfield 1945; Wyatt 1959;

Moring and Youker 1979). Spawning may

occur in selected areas of large

streams (Moring and Youker 1979).

Cutthroat trout spawning occurs in

water velocities ranging from 0.11 to

0.56 m/s in Washington (Hunter 1973)

and 0.30 to 0.90 m/s in northern

California (Hooper 1973).

Coastal cutthroat trout prefer to

spawn in the headwater tributaries of

larger streams. Summer water flow

rates in these natal creeks seldom

11
exceed 0.28 m3/s during low flow and

most average 0.12 m3/s (Johnston

1982).

Water Depth

Cutthroat trout spawn at the tail

ends of pools at depths as shallow as

lo-15 cm (June 1981) or as deep as 1 m

(Johnston and Mercer 1976). Hunter

(1973) found cutthroat spawning in

water 6-40 cm deep. June (1981) found

some redds in riffle areas.

In streams, adult cutthroat trout

are found in the deeper pools and

slower velocity water, while the fry

are found in shallower, faster areas

(Griffith 1972; June 1981).

Timber Harvest

Logging practices can directly and

indirectly change the physical

environments in the small headwater

streams that are the important

spawning and rearing areas for coastal

cutthroat trout. Such changes can

significantly alter cutthroat trout

populations (Hall and Lantz 1969;

Moring 1975; Lantz 1976). Poor logging

practices in the vicinity of small

streams can cause a variety of changes

that are detrimental to the cutthroat

trout. These include (1) an increase

in both the maximum and the diurnal

fluctuation of the water temperature

(Hall and Lantz 1969; Moring 1975;

Ringler and Hall 1975; Chamberlin

1982); (2) decreases in dissolved

oxygen in both surface and intragravel

water (Hall and Lantz 1969; Moring

1975; Ringler and Hall 1975;

Chamberlin 1982); (3) increased sediments in the stream ana changes in the

amount of fines present in the gravel

(Hall and Lantz 1969; Moring 1975;

Chamberlin 1982); (4) increased stream

flow resulting in velocity and depth

changes (Moring 1975; Chamberlin

1982); (5) alteration of the amount of

woody debris in the stream causing pH

changes (Chamberlin 1982); and (6)

loss of terrestrial and aquatic

vegetation used as food sources and

rearing habitat (Moring and Lantz

1974; Moring 1975).

THE FISHERY

Angling for sea-run cutthroat trout

occurs in both the marine and freshwater environments (Hisata 1973;

Johnston and Mercer 1976; Washington

1977; Mercer 1982). Although only

limited data are available on total

annual harvest and fishing pressure,

the sea-run cutthroat trout fishery

represents an important component of

the sport fisheries of the Pacific

Northwest.

Angler surveys conducted by the U.S.

National Marine Fisheries Service in

1974 in the marine area of Puget

Sound, Washington, indicated that

cutthroat trout were second only to

salmon in popularity among saltwater

anglers (Johnston and Mercer 1976).

An earlier Washington Department of

Game survey in 1964 showed a total of

43,700 anglers fished for anadromous

cutthroat in marine areas of

Washington State (Johnston and Mercer

1976). The average per capita

expenditure was $25 per day in 1974,

with the total value to the State's

economy estimated at $8,850,000 per

year. Although this data may have

been biased, there is no reason to

believe a decline in participation has

occurred in the marine fishery. The

total participation in and value of

the freshwater fishery for anadromous

cutthroat in Washington has never been

evaluated. However, over 1,800

man-days were expended in 1970

pursuing cutthroat trout in saltwater

on southern Hood Canal (Johnston and

Mercer 1976).

In Oregon in 1972, anglers caught an

estimated 126,000 adult cutthroat, 86%

from coastal streams and 14% from the

Columbia River and its tributaries

(Johnston and Mercer 1976). They

estimated the annual value of the

stream cutthroat trout fishery to

Oregon's economy was $3,750,000, based

12
on an average per capita expenditure

estimated at $30 per day in Washington

State by Oliver et al. (1975). The

projected catch in Washington and its

impact on the State's economy has been

assumed to be greater than in Oregon

due to greater numbers of streams in

Washington State that contain cutthroat trout and a larger human

population close to these streams

(Johnston and Mercer 1976).

Tipping (1981) indicated that 84%

of all sea-run cutthroat trout were

caught by anglers targeting on them,

while 16% were caught incidental to

salmon and steelhead. Most angling

effort was by plunkers, with boaters

second, and drift fishermen third

(Tipping and Springer 1980; Tipping

1981). Overall cutthroat trout

angling effort is highest in August

(Tipping and Springer 1980), but the

highest catch was in the first 2 weeks

of September (Tipping 1981). Most

anglers caught one fish or less per

trip (Tipping and Springer 1980;

Tipping 1981). The majority of fish

caught were sexually mature (Tipping

1981).

The amount of angler participation

will likely double between 1972 and

1990 in Oregon and a similar trend may

occur in Washington (Johnston and

Mercer 1976). The value of the

cutthroat fishery to both Oregon and

Washington economies is expected to

increase along with fishing pressure;

however, it is anticipated that the

native stocks of sea-run cutthroat

will not increase and may decline due

to habitat degradation and possible

overfishing (Johnston and Mercer

1976). New restrictive regulations (2

fish per day and 12-inch minimum

size) within British Columbia and

Washington, which were designed to

increase spawner escapement, have

significantly increased the abundance

of older, larger fish in many

watersheds (J. M. Johnston, unpubl.

data). Johnston (1980) indicated that

a two-fish limit in the Stillaguamish

River would reduce the total harvest

of sea-run cutthroat trout by about

20%. A 14-inch minimum size limit on

sea-run cutthroat caught in all

marine waters and selected freshwater

streams was put in force in

Washington State in 1987.

Concurrent with habitat protection,

agencies responsible for the management of sea-run cutthroat populations

have attempted to spread the harvestable portion of the stocks to more

anglers by imposing restrictions on

catch and possession, size, season,

and gear.

13

Allen, K.R. 1969. Limitations on

production in salmonid populations

in streams. Pages 3-18 in T.G.

Northcote, ed. Symposium onisalmon

and trout in streams. H.R.

MacMillan Lectures in Fisheries,

University of British Columbia,

Vancouver.

Anderson, B.G., and D.W. Narver.

1975. Fish populations of Carnation

Creek and other Barkley Sound

streams--1974: data record and progress report. Fish Res. Board Can.

MS Rep. No. 1351. 73 pp.

Andrusak, H., and T.G. Northcote.

1971. Segregation between adult

cutthroat trout (Salmo clarki) and

Dolly Varden (Salvelinus malma) in

small coastal British Columbia

lakes. J. Fish. Res. Board Can. 28

(7):1259-1268.

Armstrong, R.H. 1971. Age, food, and

migration of sea-run cutthroat

trout, Salmo clarki, at Eva Lake,

Southeastern Alaska. Trans. Am.

Fish. Sot. 100 (2):302-306.

Bachman, R.W. 1958. The ecology of

four north Idaho trout streams with

reference to the influence of forest

road construction. M.S. Thesis.

University of Idaho, Moscow. 97 pp.

Baxter, G.T., and J.R. Simon. 1970.

Wyoming fishes. Wyoming Game Fish

Dep. Bull. 4. 168 pp.

Behnke, R.J., and M. Zarn. 1976.

Biology and management of threatened

and endangered western trout. U.S.

Dep. Agric. For. Serv. Gen. Tech.

Rep. RM-28. 45 pp.

LITERATURE CITED

Bell, M.C. 1973. Fisheries handbook

of engineering requirements and biological criteria. U.S. Army Corps

of Engineering North Pacific Div.,

Contract DACW57-68-C-0086. 92 PP.

Bianchi, D.R. 1963. The effects of

sedimentation on egg survival of

rainbow trout and cutthroat trout.

M.S. Thesis. Montana State College,

Bozeman. 28 pp.

Buckley, R.V. 1966. Catch of the

1965 tidewater cutthroat sport fishery and notes on the life history of

the coastal cutthroat in the Siuslaw

River, Oregon. Oreg. Game Comm.

Fish. Res. Rep. No. 4, Oregon State

University, Corvallis. 29 pp.

Bustard, D.R., and D.W. Narver. 1975.

Preferences of iuvenile coho salmon

(Oncorhynchus ki‘sutch) and cutthroat

trout (Salmo clarki) relative to

simulated alterationof winter habitat. 3. Fish. Res. Board Can.

32(3):681-687.

Campton, D. 1980. Genetic structure

of sea-run cutthroat populations in

the Puget Sound area. Sea-run status Report, 1980. Wash. State Game

Dep. Rep. 80-14:185-186.

Campton, D.E., and F.M. Utter. 1985.

Natural hybridization between steelhead trout (Salmo gairdneri) and

coastal cutthroat trout (Salmo

- - clarki clarki) in two Puget Sound

streams. Can. J. Fish. Aquat. Sci.

42(1):110-119.

Carlander, K.D. 1969. Handbook of

freshwater fishery biology. Iowa

State University Press, Ames. Vol.

1. 752 pp.

15
Chamberlin, T.W. 1982. Timber harvest. Pages l-30 in W.R. Meehan,

ed. Influence of forest and rangeland management on anadromous fish

habitat in Western North America.

U.S. Dep. Agric. For. Serv. Gen.

Tech. Rep. PNW-136.

Cooper, E.L. 1970. Growth of cutthroat trout (Salmo clarki) in Chef

Creek, Vancouver -I- British

Columbia. J. Fish. Res. Board Can.

27:2063-2070.

Cope, 0-B. 1957. The choice of

spawning sites by cutthroat trout.

Proc. Utah Acad. Sci. Arts Lett. 34:

73-79.

Cramer, F.K. 1940. Notes on the

natural spawning of cutthroat trout

(Salmo clarki clarki) in Oregon.

Proc. Sixthcificci. Congr. No.

3: 335-339.

Dewitt, J.W. 1954. A survey of the

coast cutthroat trout, Salmo clarki

clarki Richardson, in Calf=

Calif. Fish Game 40(3):329-335.

Dimick, R.E., and F. Marryfield.

1945. The fishes of the Willamette

River system in relation to

pollution. Oregon State College

Eng. Exp. Stn. Bull. No. 20. 58 pp.

Dimick, R.E., and D.C. Mote. 1934. A

preliminary survey of the food of

Oregon trout. Oregon State College

Agric. Exp. Stn. Bull. No. 323. 23

PP.

Doudoroff, P., and D.L. Shumway.

1970. Dissolved oxygen requirements

of freshwater fishes. FAO (Food

Agric. Organ.) United Nations, Fish.

Tech. Pap. 86. Rome. 291 pp.

Dwyer, W.P., and R.H. Kramer. 1975.

The influence of temperature on

scope for activity in cutthroat

trout, Salmo clarki. Trans. Am.

Fish. Sot. 104(3):552-554.

Dymond, J.R. 1932. The trout and

other game fishes of British

Columbia. Can. Dep. Fish., Ottawa,

Canada. 51 pp.

Fuss, H.J. 1978. Some life history

characteristics obtained by scale

analvsis of sea-run cutthroat trout

(Salmo clarki clarki) from streams

near Forks. Washinaton. Pages 127-

133 in J.R: Moring; ed. Proceedings

of the Wild Trout-Catchable Trout

Symposium. Oregon Dep. Fish Wildl.,

Eugene.

Fuss, H.J. 1982. Age, growth and

instream movement of Olympia

Peninsula coastal cutthroat trout

(Salmo clarki clarki). M.S. Thesis.

UniversityfWashington, Seattle.

191 pp.

Fuss, H.J. 1984. Age, growth and

instream movement of Olympia Peninsula coastal cutthroat trout (Salmo

clarki clarki). Pages 125-134

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

Proceedings of Olympic Wild Fish

Conference. U.S. Park Service and

Peninsula College. Port Angeles,

Washington.

Giger, R.D.

agement of

in Oregon.

Fish Res.

Glova, G.J.

1972. Ecology and mancoastal cutthroat trout

Oregon State Game Comm.

Rep. No. 6. 61 pp.

1984. Management implithe distribution and diet

._

cations of

of sympatric populations of juvenile

coho salmon and coastal cutthroat

trout in small streams in British

Columbia, Canada. Prog. Fish. Cult.

46(4):269-278.

Glova, G.J., and J.C. Mason. 1976.

Interactive ecology of juvenile salmon and trout in streams. Fish.

Res. Board Can. MS Rep. Ser. No.

1391. 24 PP.

Glova, G.J., and J.C. Mason. 1977.

Interactions for food and space

between sympatric populations of

16
underyearling coho salmon and coastal cutthroat trout in a stream simulator during summer. Fish. Res.

Board Can. MS Rep. Ser. No. 1428.

36 PP.

Golden, J.T. 1975. Lethal temperatures for coastal cutthroat trout

under fluctuating temperature regimes. Oregon Fish Wildl. Dep. Rep.

Unpubl. MS. 7 pp.

Griffith, J.S. 1972. Comparative

behavior and habitat utilization of

brook trout (Salvelinus fontinalis)

and cutthroat trout (Salmo clarki)

in small streams in noXK%Idaho.

Res. Board Can.

Griffith, J.S. 1975. Utilization of

invertebrate drift by brook trout

(Salvelinus fontinalis) and cutthroat trout (Salmo clarki) in small

streams in IdaT Trans. Am. Fish. -

sot. 103(3):440-447.

Hall, J.D., and R.L. Lantz. 1969.

Effects of logging on the habitat of

coho salmon and cutthroat trout in

coastal streams. Pages 355-375 in

T.G. Northcote, ed. Symposium On

salmon and trout in streams. University of British Columbia,

Vancouver.

Hanson, D.L. 1977. Habitat selection

and spatial interaction in allopatric and sympatric populations of

cutthroat and steelhead trout.

Ph.D. Dissertation. University of

Idaho, Moscow. 76 pp.

Hart, J.L. 1973. Pacific fishes of

Canada. Fish. Res. Board Can.

Bull. 180. 740 pp.

Hartman, G.F., and C.A. Gill. 1968.

Distributions of juvenile steelhead

and cutthroat trout (Salmo gairdneri

and S. clarki clarki)within streams

in s&.mrnBritish Columbia. J.

Fish. Res. Board Can. 25(1):33-48.

Hunter, J.W. 1973. A discussion of

game fish in the State of Washington

as related to water requirements.

Wash. State Dep. of Ecol., Olympia.

66 PP.

Idyll, C. 1942. Food of rainbow,

cutthroat and brown trout in the

Cowichan River system, B.C. J.

Fish. Res. Board Can. 5(5):448-457.

Irving, J.S. , and T.C. Bjornn. 1984.

Heath, W.G. 1963. Thermoperiodism in

sea-run cutthroat trout (Salmo

- -

clarki clarki). Science 142:486-

488.

Hickman, T.J. 1977. Studies on relict populations of Snake Valley

cutthroat trout in western Utah

1976. U.S. Bureau of Land Management, Salt Lake City, Utah. 41 PP.

Hisata, J.S. 1973. Evaluation of

stocking hatchery reared sea-run

cutthroat trout in streams of Hood

Canal. Wash. State Game Dep. Final

Rep. AFS-44. 38 pp.

Hooper, D.R. 1973. Evaluation of the

effects of flows on trout stream

ecology. Calif. Dep. Eng. Res.,

Emeryville. 97 pp.

Horner, N., and T.C. Bjornn. 1976.

Survival, behavior, and density of

trout and salmon fry in streams.

Univ. Idaho, For. Wildl. Exp. Stn.,

Contract 56, Prog. Rep. 1975. 38 pp.

Effects of substrate size composition on survival of kokanee salmon

and cutthroat and rainbow trout.

Idaho Coop. Fish. Res. Unit Tech.

Rep. 84-6. 21 pp.

Johnston, J.M. 1980. Stillaguamish

River sea-run cutthroat creel survey

(1979). Pages 208-219 in Sea-run

cutthroat census report, 1980. Wash.

State Game Dep. Rep. No. 80-14.

Johnston, J.M. 1982. Life histories

of anadromous cutthroat with emphasis on migratory behavior. Pages

17
123-127 in E.L. Brannon and E.O.

Salo, eds- Salmon and trout migratory behavior symposium. University of Washington Press, Seattle.

Johnston, J.M., and S.P. Mercer.

1976. Sea-run cutthroat in saltwater pens: broodstock development

and extended juvenile rearing (with

a life history compendium). Wash.

State Game Dep. Fish. Res. Rep.

AFS-57-1. 92 pp.

Jones, D.E. 1972. Life history study

of sea-run cutthroat trout and

steelhead trout in southeast Alaska.

Federal aid in fish restoration,

annual report of progress, 1971-

1972. Alaska Dep. Fish Game Proj.

F-9-4, 13(G-ll-l):l-18.

Jones, D. E. 1973. Steelhead and searun cutthroat trout life history in

southeast Alaska. Anadromous fish

studies, annual report of progress,

1972-1973. Alaska Dep. Fish Game

Proj. AFS-42, 14(AFS-42-l):ll-18.

Jones, 0. E. 1974. Life history of searun cutthroat trout in southeast

Alaska. Anadromous fish studies,

annual report of progress, 1973-

1974. Alaska Dep. Fish Game Proj.

AFS-42, 15(AFS-42-22):15-31.

Jones, D.E. 1975. Life history of

sea-run cutthroat trout in southeast

Alaska. Anadromous fish studies,

annual performance report, 1974-

1975. Alaska Dep. Fish Game Proj.

AFS-42, 16 (AFS-42-3-B):Section J,

23-24.

Jones, D.E. 1976. Life history of searun cutthroat trout in southeast

Alaska. Anadromous fish studies,

annual performance report, 1975-

1976. Alaska Dep. Fish Game Proj.

AFS-42, 117 (AFS-42-4-B):Section M,

29-53.

Jones, D.E. 1977. Development of techniques for enhancement of anadromous

cutthroat trout in southeast Alaska.

Anadromous fish studies, annual

performance report, 1976-1977.

Alaska Dep. Fish Game Proj. AFS-42,

18 (AFS-42-5-BV):28-42.

Jones, D. E. 1979. Development of

techniques for enhancement of

anadromous cutthroat in southeast

Alaska. Anadromous fish studies,

annual performance report, 1978-

1979. Alaska Dep. Fish Game Proj.

AFS-42, 20 (AFS-42-7-B):27-57.

June, J.A. 1981. Life history and

habitat utilization of cutthroat

trout (Salmo clarki) in a headwater

stream inthe Olympic Peninsula,

Washington. M.S. Thesis. University

of Washington, Seattle. 116 pp.

Lantz, R.L. 1976. Protection of salmon and trout streams in logging

operations. Pages 14-20 in A.P.

Grove, ed. Stream management of

salmonids. Trout-Winter Supplement,

Denver, Colorado.

Lowery, G.R. 1965. Movement of cutthroat trout, Salmo clarki clarki

(Richardson), in three

--

Oregon

coastal streams. Trans. Am. Fish.

Sot. 94(4):334-338.

Lowery, G.R. 1966. Production and

food of cutthroat trout in three

Oregon coastal streams. J. Wildl.

Manage. 30 (4):754-767.

Martin, D.J. 1984. Growth, food consumption, and production of cutthroat in relation to food supply

and water temperature. Pages 135-

144 in J.M. Walton and D.B. Houston,

eds.- Proceedings of Olympic Wild

Fish Conference. U.S. Park Service

and Peninsula College. Port

Angeles, Washington.

McAfee, W.R. 1966. Lahonton cutthroat trout. Pages 225-231 in A.

Calhoun, ed. Inland Fisheries-anagement. Calif. Dep. Fish Game,

Sacramento.

Merriman, D. 1935. The effect of

temperature on the development of

18
the eggs and larvae of the cutthroat

trout (Salmo clarki clarki Richardson). J.p.. 12(4):297-305.

Mercer, S.P. 1982. Sea-run cutthroat: Broodstock development and

evaluation of enhancement techniques. Wash. State Dep. Game Fish.

Res. Rep. F-68-R-6. 55 pp.

Mercer, S.P., and J.M. Johnston.

1979. Sea-run cutthroat: development and evaluation of a new enhancement technique. Wash. State

Game Dep. Fish. Res. Rep. F-68-R-3.

45 PP.

Michael, J.H. 1983. Contribution of

cutthroat trout in headwater streams

to the sea-run population. Calif.

Fish Game 69(2):68-76.

Miller, R.B. 1957. Permanence and

size of home territory in stream

dwelling cutthroat trout. J. Fish.

Res. Board Can. 14(5):687-691.

Moring, J.R. 1975. The Alsea watershed study: effects of logging on

the aquatic resources of three headwater streams of the Alsea River,

Oregon. Part III-Discussion and

recommendations. Oreg. Dep. Fish

Wildl. Fed. Aid Proj. AFS-58. Rep.

9. 24 PP.

Moring, J.R., and R.L. Lantz. 1974.

Immediate effects of logging on the

freshwater environment of salmonids.

Oreg. Wildl. Comm., Res. Dev. Proj.

AFS-58, Final Rep., Portland. 101

PP.

Moring, J.R., and R.L. Lantz. 1975.

The Alsea watershed study: Part I--

biological studies. Oregon Dep. Fish

Wildl., Fish Res. Rep. 9. 66 pp.

Moring, J.R., and R.L. Youker. 1979.

Oregon rainbow and cutthroat trout

evaluation. Oreg. Dep. Fish Wildl.

Proj. F-94-R. Final Rep. 64 pp.

Nicholas, J.W. 1978. A review of

literature and unpublished information on cutthroat trout (Salmo

clarki clarki) of the Willamette - -

watershed. Oreg. Dep. Fish. Wildl.

Res. Sect., Inf. Rep. Ser. Fish. No.

78-l. 20 PP.

Nickelson, T.E., and G.L. Larson.

1974. Effect of weight loss on the

decrease of length of coastal

cutthroat trout. Prog. Fish-Cult.

36(2):90-91.

Nickelson, T.E., and R.R. Reisenbichler. 1977. Streamflow requirements of salmonids. Oreg. Dep. Fish

Wildl. Prog. Rep. AFS-62. 24 P P.

Oliver, W.H., C. Young, and D. Eldred.

1975. A short form for bioeconomic

evaluations of wildlife in Washington State. Wash. State Game Dep.

Applied Res. Bull. No. 7. 15 PP.

Qadri, S.U. 1959. Some morphological

differences between the subspecies

of cutthroat trout, Salmo clarki

clarki and Salmo clarknisi

British Columbia. J. Fish.kes.

Board Can. 16(6):903-922.

Reiser, D.W., and T.C. Bjornn. 1979.

Habitat requirements of anadromous

salmonids. Pages l-54 in W.R.

Meehan, ed. Influence of forest and

rangeland management on anadromous

fish habitat in the Western United

States and Canada. U.S. Dep. Agric.

For. Serv. Gen. Tech. Rep. PNW-96.

Ringler, N.H., and J.D. Hall. 1975.

Effects of logging on water temperature and dissolved oxygen in

spawning beds. Trans. Am. Fish.

Sot. 104(1):111-121.

Royal, L.A. 1972. An examination of

the anadromous trout program of the

Washington State Game Department.

Wash. State Game Dep. Final Rept.

AFS-49. 197 pp.

Schultz, D.C., and T.G. Northcote.

1972. An experimental study of

feeding behavior and interaction of

coastal cutthroat trout (Salmo

19
clarki clarki) and Dolly Varden

(Salvelinilma). J. Fish. Res.

Board Can. 29m55-565.

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

Freshwater fishes of Canada. Fish.

Res. Board Can. Bull. 184. 966 pp.

Sekulich, P.T. 1974. Role of the

Snake River cutthroat trout (Salmo

clarki ss.) in fishery management.

M.S. Thesis. Colorado State University, Fort Collins. 102 pp.

Simenstad, C.A., and W.J. Kinney.

1978. Trophic relationships of outmigrating chum salmon in Hood Canal,

Washington, 1977. Wash. State Dep.

Fish. Final Rep. Contract No. 877.

FRI-UW-7810. 76 pp.

Smith, C.E., W.P. Dwyer, and R.G.

Piper. 1983. Effect of water temperature on egg quality of cutthroat

trout. Prog. Fish-Cult. 45(3):176-

178.

Smith, O.R. 1941. The spawning habits

of cutthroat and eastern brook

trouts. J. Wildl. Manage. 5(4):141-

147.

Snyder, G.R., and H.A. Tanner. 1960.

Cutthroat trout reproduction in the

inlets to Trappers Lake. Cola.

Fish. Game Tech. Bull. 7. 85 PP.

Sumner, F.H. 1952. A contribution to

the life history of the cutthroat

trout in Oregon. Oregon State Game

Commission, Salem. 142 pp.

Sumner, F.H. 1953. Migration of salmonids a Sand Creek

Trans. A: Fish Sot.

Oregon.

82:139-150.

Thomasson, T. 1978. Aae and arowth

of cutthroat trout (Salmo clarki

clarki, Richardson) i-the Rogue

River, Oregon. M.S. Thesis. Oregon

State University, Corvallis. 65 pp.

Thompson, K. 1972. Determining

stream flows for fish life. Pages

59-74 in Proceedings of the - Instream

Flow Requirement Workshop. Pacific

Northwest River Basin Commission,

Vancouver, Wash.

Tipping, J.M. 1981. Cowlitz sea-run

cutthroat study 1980-81. Wash.

State Game Dep. Rep. No. 81-12. 26

PP.

Tipping, J.M. 1986. Effect of release size on return rates of hatchery sea-run cutthroat trout. Prog.

Fish-Cult. 48(3):195-197.

Tipping, J.M., and S.G. Springer.

1980. Cowlitz River sea-run cutthroat creel census and life history

study. Pages 106-126 in Sea-run

cutthroat census repofi, 1980.

Wash. State Game Dep. Rep. No.

80-14.

Trojnar, J.R. 1972. Ecological evaluation of two sympatric strains of

cutthroat trout. M.S. Thesis.

Colorado State University, Fort

Collins. 59 pp.

Trojnar, J.R., and R.H. Behnke. 1974.

Management implications of ecological segregation between two introduced populations of cutthroat trout

in a small Colorado lake. Trans.

Am. Fish. sot. 103(3):423-430.

Trotter, P.C. 1987. Cutthroat:

native trout of the West. Colorado

Associated University Press,

Boulder, Colo. 219 pp.

Washington, P. 1977. The sea-run cutthroat trout resource and sport

fishery. Mar. Fish. Rev. 39(12):

20-22.

Wesche, T.A. 1974. Relationship of

discharge reductions to available

trout habitat for recommending

suitable stream flows. Wyo. Water.

Resour. Res. Inst. Ser. No. 53. 71

PPWilzbach, M.A. 1985. Relative roles

of food abundance and cover in

determining the habitat distribution

20
of stream-dwelling cutthroat trout

(Salmo clarki). Can. J. Fish.

Aquat. Sci.(10):1668-1672.

M.S. Thesis. Oregon State University, Corvallis. 60 pp.

Wydoski, R., and R.W. Whitney. 1978.

Wyatt, B. 1959. Observations on the Inland fishes of Washington. Unimovements and reproduction of the versity of Washington Press,

Cascade form of cutthroat trout. Seattle. 220 pp.

21
10272 -101

REPORT DOCUMENTATION 1. =EpoRT NO. 2. 3. ReCkWent’s Accession No.

PAGE Biological Report 82 (11.86)*

1. Title and Subtitle 5. Repmt DM.

Species Profiles: Life Histories and Environmental Requirements

of Coastal Fishes and Invertebrates (Pacific Northwest)--Sea-run

January 1989

6.

cutthroat trout

7. AuthorW S. Pwfonning Orsaniration Rept. No

Gilbert 6. Pauley, Kevin Oshima, Karen L. Bowers, and Gary L. Thomas

9. PerforminS Organization Name and Addnss lo. PloiutlTasklWerk Unit No.

Washington Cooperative Fishery Research Unit

University of Washington 11. b.-StnCt(C) or Grant(G) No.

Seattle, WA 98195 (C)

--_ ______

12. SponsorinS O~~nlxatlpn Name end Address (G)

U.S. Department of the Interior U.S. Army Corps of Engineers 13. TYPa of R~~rt & Period Cwmd

Fish and Wildlife Service Waterways Experiment Station

Research and Development P.O. Box 631

National Wetlands Research Center Vicksburg, MS 39180 II.

15.

Washington, DC 20240

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

Supplmnmtary NOtas

F

16. Ahtract (Limit: 200 words)

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

history, and environmental requirements of coastal aquatic species. They are designed to

assist with environmental impact assessments. The sea-run cutthroat trout (Salmo clarki

clarki) is anadromous and is found in most coastal streams from Southeasmska

Northern California. A thriving sport fishery exists both in these freshwater streams

and in protected marine waters. Many of the small streams containing cutthroat trout can

be adversely altered by poor timber operations. Optimum temperature for incubating is 10

to 11 OC and eggs hatch in 28-40 days. Optimum temperature for juveniles is 15 “C and

ability to swim is lost at about 28 “C. Adults prefer fairly slow-moving water with

plenty of cover. Spawning occurs in small diameter gravel. Like steelhead trout, they

may return from saltwater to spawn several times.

17. Oocumen( Analysis a. Descriptors

Temperature

Estuaries

Animal migrations

b. Identlfien/Op.n.Endad T.rm,

Feeding habits

Trout

Life cycles

Sea-run cutthroat trout

Coastal cutthroat trout

Salmo clarki clarki ---

c. COSATI FieldlGmup

Ecological role

Environmental requirements

Timber harvest

lb Availability SMement

Unlimited distribution

19. kcurdy Class (This Rwcet) 21. No. of Pales

Unclassified 21 - -

20. Suurity Class Crhir Pace) P. Prim

Unclassified

ie. ANSI-239.18) OPTIONAL FORM 272 (4-71

(Fomrly Nll%35)

Dmpmtment d COrnrnwc~

V’
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

FISH AND WILDLIFE SERVICE

TAKE PRIDE

in America

i

UNITED STATES

DEPARTMENT OF THE INTERIOR

FISH AND WILDLIFE SERVICE

National Wetlands Research Center

NASA-Slide11 Computer Complex

1010 Gause Boulevard

Slidell, LA 70458

PDSTAQE AND FEE8 PAID

&a. DePARrMENr OF THE INTERIOR

lNl423

OFFICIAL BUSINESS

PENALTY FOR PRIVATE USE, $300