9432

• UCREFRP Catalog Number: 9432
• Author: Modde, T. and M. Fuller.
• Title: Feasibility of Channel Catfish Reduction in the Lower Yampa River.
• USFW Year: 2002.
• USFW - Doc Type: Vernal.
• Copyright Material: NO

may have an important linkage to the deli sting actions regarding humpback chub.

Given the consensus that nonnative fishes have a detrimental impact on imperiled river

fishes, few efforts to reduce nonnative species have been demonstrated in the upper Colorado

River basin (Brooks et al. 2000, Crowl and Badame 2000). Nonnative fishes control options for

the upper Colorado River basin were proposed by both Lentsch et al. (1996) and Tyus and

Saunders (1996) based on literature reviews and the opinions of regional experts. Both reports

suggested mechanical and biological methods as the more feasible means of reducing channel

catfish in the upper Colorado River basin. The potential to significantly reduce channel catfish

populations by mechanical methods has been demonstrated by overharvest in its native habitat in

the Missouri River (Stanovick 1999; Mestl1999; Pitlo 1967). Given the recommendations by

Lentsch et al. (1996) and Tyus and Saunders (1996), and the observed success in the Missouri

River, mechanical removal was chosen as a method to evaluate the feasibility of reducing channel

catfish from the lower Yampa River in Dinosaur National Monument.

The purpose of our study was to determine if we could mechanically remove significant

numbers of channel catfish in selected reaches of the Yampa River, which supports all life stages

of humpback chub (Karp and Tyus 1990) and adult Colorado pikeminnow. The specific objectives

of this study were to: 1) determine the most effective mechanical methods of removal, 2) determine

the effectiveness of mechanical removal in reducing the channel catfish population size in the

Yampa River Canyon (rm 10 - 45), and 3) make recommendations on how to effectively remover
channel catfish from the Yampa River on a larger scale.

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