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

regression was use to test the presence or absence of a length gradient in catfish collected by

electrofishing in the lower Yampa River. Relative weight (Wege and Anderson 1978), using the

standard weight proposed by Brown et al. (1995) was used to describe condition of channel catfish

captured by anglers. A GLM anova was also used to compare relative weight by treatment reach.

The significance level for all statistical tests was set at 0.05.

Results

Gear Efficiency

Catch rate of channel catfish was highest for electrofishing (12.4 fish/hour, Table 3) in

1998. Angling had the second highest rate, ranging between 3.3 and 4.6 fish/hr. Very few catfish

were captured with hoop and fyke nets with catch rates averaging only 0.088 and 0.018 fish/hr,

respectively. Although catch rate was highest for electro fishing, the efficiency of removal, i.e.,

cost per fish removed, was lowest for angling. Cost per fish removed by electrofishing was $35.64

per fish compared to $19.34 per fish by angling in 1998. Cost per fish for angling in 1999 was

$16.25 per fish. The cost per fish captured by fyke nets and hoop nets were $89.85 and $431.81

per fish, respectively. Given catch per trip criteria (i.e., cost/fish), angling was the most effective

means of removing channel catfish. Anglers removed 1,150 fish during three trips in 1998

representing 86.4% of the fish removed in 37.5% of the trips. Fyke and hoop nets had low catch

rates removing less than 5% of catfish in 62.5% of the trips. However, both fyke and hoop nets

were effective in capturing native fishes, particularly roundtail chub ( Table 4). Trot lines captured

only 10 channel catfish from seven sets, and were discontinued following capture and injury to

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