7361

• UCREFRP Catalog Number: 7361
• Author: Tyus, H. M. and N. J. Nikirk.
• Title: Abundance, Growth, and Diet of Channel Catfish,
• USFW Year: 1989.
• Copyright Material: NO

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(Hubley, 1963), we believe that growth was reduced by a limited resource base,
short growing seasons, and low water temperatures.
Diet--Most of the 755 channel catfish stomachs inspected contained food
(76.2%), but 23.8% were empty (Yampa River: 21.75%, n=75; Green River: 25.6%,
n=105). Aquatic invertebrates were present in 31% of stomachs containing food
(n=575); 28% contained vascular plants, including horsetail, Equisetum sp.
(Sphenopsida), juniper berries, seeds, twigs, and leaves; 22% contained
terrestrial insects; 10% contained algae, detritus, and miscellaneous items;
7% contained fish; and 1.5% contained mice (Table 3). These foods are similar
to those in other locations (Bailey and Harrison, 1948; Carlander, 1969;
Davis, 1959; Moyle, 1976).
Channel catfish utilized different foods depending on size (and
presumably age), river section, and season. Although there were some
differences in type of foods selected by different-sized fish in both the
Green and Yampa rivers, many of these differences were not significant when
the rivers were combined. The only size-specific difference in diet was
between individuals consuming vertebrates and individuals consuming other
foods (Table 3). Terrestrial insects (e.g., Mormon crickets) and vascular
plants (e.g., horsetails) were relatively abundant in the Yampa and Green
rivers in Dinosaur National Monument in late spring to mid-summer and were
heavily utilized by channel catfish (Tyus and Minckley, 1988). However, these
items are generally scarce in the lower Green River. An algae, Cladophora sp.
(Clorophyta), transported into the Dinosaur National Monument area of the
Green River from the clear tailwaters of Flaming Gorge Dam, was a common food
item of channel catfish in that location, as previously reported by Banks
(1964).