7778

• UCREFRP Catalog Number: 7778
• Author: Tyus, H. M. and N. J. Nikirk
• Title: Abundance, Growth, and Diet of Channel Catfish,
• USFW Year: 1990
• Copyright Material: YES

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JUNE 1990

ABUNDANCE, GROWTH, AND DIET OF CHANNEL
CATFISH, ICTALURUS PUNCTA TUSJ IN THE
GREEN AND YAMPA RIVERS,
COLORADO AND UTAH

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HAROLD M. Tyus AND NEIL J. NIKIRK

United States Fish and Wildlife Service, 7680 West Highway 40 #7270,
Vernal, UT 84078
University of Washington, Fisheries Research Institute WH-70,
Seattle, WA 98795

ABSTRACT-Channel catfish were widely distributed in 517 km of the mainstream Green and 74
km of the lower Yainpa rivers in 1987 and 1988. The fish was most abundant in rocky canyon habitats
(average stream gradient >2 m/km), where adult fish comprised 14% of e1ectrofishing and 70% of
angling catch. Pectoral spine sections of 364 channel catfish of 27 to 756 mm total length ranged in
age from 0 to 22 years respectively, with an average annual growth range of 17 to 53 mm. No difference
in growth or condition factor was detected among catfish collected in eight river reaches. Growth of
channel catfish in the Green River basin was judged slow in comparison to other areas of the United
States and was attributed, i,n part, to cold water temperatures, short growing seasons, and elevated
summer flow conditions. Channel catfish consumed a variety of food items, but piscivory was limited
to larger fish (average length 420 mm). Of 575 stomachs with food (76.2%), 31% contained aquatic
invertebrates, 28% contained vascular plant material, 22% contained terrestrial insects, 10% contained
algae and detritus, and 8.5% contained fish and mice. The abundance, widespread distribution, and
omnivorous feeding behavior of this introduced fish may affect populations of rare and endangered
fishes in the Green River basin.

1

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Native to North America, channel catfish (Ic-
talurus punctatus) was formerly restricted to larg-
er streams tributary to the Mississippi River,
Great Lakes, and Gulf of Mexico (Jordan and
Evermann, 1896) but has been widely introduced
elsewhere (Lee et al., 1980). It was stocked in
the Colorado River basin as early as 1892 (Allen
and Roden, 1978) and introduced into lakes in
Utah about 1888; many stockings were subse-
quently made into the Green and Colorado rivers
(Sigler and Miller, 1963).
The channel catfish is common to abundant in
rivers of the upper Colorado River basin (Fig.
1), including the Green and Yampa rivers in Col-
orado and Utah (Holden and Stalnaker, 1975a,
19756; Tyus et al., 1982). Originally proposed
to enhance sportfishing in a faunally depauperate
river (Jordan, 1891), fishing for channel catfish
in the Green and Yampa rivers is virtually non-
existent. However, establishment of the fish in
the Colorado River basin has been implicated in
the decline of rare and endangered native fishes

(Holden and Stalnaker, 1.975a; Marsh and Brooks,
1989).
Little is known about growth or food habits of
channel catfish in the Green and Yampa rivers
or about its interactions with the native fauna.
Although channel catfish are locally abundant,
young fish examined at the end of the first grow-
ing season are small, and large individuals are
rare. This observation suggested that environ-
mental conditions may limit growth and hence
attainment of large size in channel catfish. T. M.
Lynch and D. G. Lemons (in litt.) reported slow
growth of 23 channel catfish in the Yampa River;
however, small sample size and lack of similar
work in other locations in the Green River basin
make these data difficult to interpret.
This study evaluated the relative abundance,
age, growth, condition, and diet of channel catfish
from different habitats in the Green and Yampa
rivers, to test the hypothesis that environmental
conditions in the Green River basin may not be
optimal for growth in this species. We discuss