9442

• UCREFRP Catalog Number: 9442
• Author: Muth, R. T. and T. E. Czapla.
• Title: Workshop Summary
• USFW Year: 2002.
• USFW - Doc Type: Designing Methods to Evaluate Stocked Fish in the Upper Colorado River, Green River, and San Juan River Subbasins.
• Copyright Material: NO

1.0 INTRODUCTION

1.1 Background

According to recovery goals for the endangered bony tail Gila elegans, Colorado pikeminnow
Ptychocheilus lucius, and razorback sucker Xyrauchen texanus (U.S. Fish and Wildlife Service
2002a, 2002b, 2002c), stocking of hatchery-produced fish is the tool for establishing founding
stocks of adult fish for creation of new populations or augmentation of existing populations.
Once adult stocks are established, self-sustaining populations are maintained through natural
reproduction and recruitment. Stocking plans for the endangered fishes in Colorado (Nesler
2001), Utah (Hudson 2001), and the San Juan River (Ryden 2001,2002; drafts) are designed to
be consistent with population-abundance criteria in the recovery goals (these criteria serve as
targets for the stocking objectives) and are based on existing knowledge of survival rates and
recognized associated uncertainties. The Upper Colorado River Endangered Fish Recovery
Program (UCRRP; upper Colorado River and Green River subbasins in Colorado and Utah) and
the San Juan River Basin Recovery Implementation Program (SJRRIP) are responsible for
monitoring stocked fish to evaluate survival, recruitment, and reproduction to detennine whether
targets of abundance and population structure are being achieved in the expected time frames.

1.2 Purpose and Objectives of Workshop

The UCRRP convened a workshop on August 28-29,2002, in Salt Lake City, Utah, to discuss
designing methods to evaluate stocked fish in the Upper Colorado River, Green River, and San
Juan River subbasins. The workshop was attended by 28 researchers, managers, and
representatives from State and Federal agencies, water users, and energy distributors involved in
the UCRRP and SJRRIP. The purpose of the workshop was to initiate development of
monitoring programs to evaluate the survival, recruitment, and reproduction of razorback sucker,
bonytail, and Colorado pikeminnow stocked in the upper Colorado River, Green River, and San
Juan River subbasins to detennine whether demographic recovery targets of fish abundance and
population structure are being achieved in the expected time frames. Objectives were to: .

1. review stocking plans (and associated capacity of existing propagation facilities, i.e.,
facilities plan) and identify necessary revisions to ensure consistency among the plans
and compatibility with the demographic recovery criteria for downlisting and delisting;

2. determine if additional "buffers" around the survival-rate estimates are needed to ensure
that stocking targets and self-sustaining populations are attained as quickly as possible;
and

3. lay-out monitoring programs for evaluation of stocking success, validation of survival
estimates, and documentation of recruitment and reproduction.

Following presentations by individual researchers or managers, a moderator solicited input from
the attendees and all infonnation was recorded for preparation of this summary.

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