9690

• UCREFRP Catalog Number: 9690
• Author: Recovery Implementation Program
• Title: Recovery Implementation Program For Endangered Fish Species In The Upper Colorado River Basin 23rd Annual Recovery Program Researchers Meeting
• USFW Year: 2002
• USFW - Doc Type: 21
• Copyright Material: NO

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inconclusive. Catch rates and relative percentage of native fishes did increase from 1998 to 1999,
but catch rate of non-native fishes also increased. Catch and relative percentage of native fishes
fell again in 2000. Catch rates of both native and non-native fish were not significantly different
from mean catch rates seen from 1986 to 1998.

Martinez, P. J. \ N. P. Nibbelink2, and D. Bennetts3

lColorado Division of Wildlife, Grand Junction, CO; 2Wyoming Geographic ['!formation Science Center,
University of Wyoming, Laramie, WY; 3Colorado Division of Wildlife, Ft. Collins, CO

A GIS Approach to Evaluate the Effectiveness of Colorado's Nonnative Fish Stocking
Regulations. A Cooperative Agreement, signed 6 November 1996 by the Directors of the state
wildlife agencies for Colorado, Utah and Wyoming, and the U.S. Fish and Wildlife Service,
Region 6, committed these parties to participate in and implement the Procedures for Stocking
Nonnative Fish Species in the Upper Colorado River Basin. Among the agreed upon components
was a requirement to ensure that all stocking of nonnative fishes in the Upper Colorado River
Basin is in compliance with the Procedures, including enacting/clarifYing appropriate regulations
for stocking of public and private waters. In January 1999, the Colorado Wildlife Commission
adopted regulatory language restricting the release of fish in waters located below 6,500 feet in
elevation surrounding critical habitat portions of the Colorado, Gunnison, White, Yampa, and
Green Rivers. These new stocking regulations, and subsequent modifications in conjunction with
existing lake license/stocking regulations, serve to meet the intent of the Procedures. The
Commission conditioned their approval of these stocking regulations, taking into account input
from the private aquaculture industry in Colorado, by requiring an evaluation of their effectiveness
in achieving a biological response. The Commission instructed the Colorado Division of Wildlife
(CDOW) to perform this evaluation and will review the overall effectiveness of the regulations
and consider their continuation or replacement after three years. Pursuant to this regulation
review the CD OW initiated a Geographic Information System (GIS) project to map and analyze
data leading to an understanding of the effectiveness of the stocking regulations. CD OW has
contracted with Wyoming Geographic Information Science Center to build the GIS database and
perform statistical analyses. Fish stocking and sampling data from 1998 to 2001 will be used in
maps and analyses of nonnative, nonsahnonid stocking frequency and locations and their spatial
and temporal relationships to fish distribution and abundance in selected river reaches. Inputs for
this evaluation include digital raster graphics (digital topo maps), aerial photographs, elevation
and floodplain designations, pond location/fish sampling information, backwater/mainstem fish
monitoring, research and removal data, and stocking records/permits for nonnative, nonsahnonid
fishes in western Colorado. Progress to date includes discussions with and written requests to
members of Colorado's Fish Health Board, the Colorado Aquaculture Association, and individual
fish vendors encouraging voluntary submission of stocking records. This presentation primarily
describes the study's methods, using grass carp as an example.

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