WSP01579

• File Number: 8240.200.10.B
• Description: UCRBRIP Annual Report
• Basin: Colorado Mainstem
• Date: 12/22/1997
• Author: UCRBRIP
• Title: 1997 Annual Reports Package Part 2
• Water Supply Pro - Doc Type: Publication

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COLORADO RIVER RECOVERY PROGRAM
FY 97 ANNUAL PROJECT REPORT

RECOVERY PROGRAM
PROJECT NlJIolBER: ~

I. Project Title: Selective Removal of Nonnative Fishes from the
Gunnison River within Colorado

II. Principal Investigator(s):

Frank K. Pfeifer, Project Leader
Charles W. McAda, FiShery Biologist

764 Horizon Drive, South Annex A
Grand Junction, Colorado 81506
[phone]: Fax [phone]
Frank [e-mail]
[e-mail]

III. Project summary:

Negative impacts from introduced fishes are one of several factors
responsible for the decline of the endangered fishes. Some of these
fishes have been introduced into the basin to provide angling
opportunities for sportsmen. They have escaped from their release
sites and occupied the mainstem rivers that provide critical habitat
for the endangered fishes. One of these species, northern pike,
occurs in low numbers in the Gunnison River where the Recovery
Program is attempting to reestablish Colorado squawfish and razorback
sucker. Northern pike were stocked into Paonia Reservoir on the
North Fork of the Gunnison River and have escaped and moved
downstream into Critical Habitat. They do not appear to be
reproducing in the Gunnison River and their numbers are very limited.
Yet a few individual predators such as pike could take a substantial
toll on young razorback suckers planned to be stocked in the area.
Because of the importance of the Gunnison River for reintroduction
efforts and because of the relatively low numbers of pike, it is an
ideal location for a study to determine if selective, mechanical
removal of nonnative fishes is a viable option to reduce their
numbers in small areas.

IV. Study Schedule: 1995-1996, Final Report 1991

V.

Relationship to RIPRAP:
III.A. Reduce negative
management activities.

Colorado River Action Plan: Gunnison River;
impacts to endangered fishes from sport fish

VI. Accomplishment of FY 97 Tasks and Deliverables, Discussion of Initial
Findings and Shortcomings:

An important recent initiative of the Recovery Program for the
endangered Colorado River fishes has been control of introduced
fishes. Introduced species have been implicated in the decline of
endangered fishes nation wide because of predation or competition for
food or space. A survey of knowledgeable upper-basin biologists
identified several species that are believed to have negative effects

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