9552

• UCREFRP Catalog Number: 9552
• Author: U.S. Fish and Wildlife Service.
• Title: Management Plan for the Big-River Fishes of the Lower Colorado River Basin
• USFW Year: 2004.
• USFW - Doc Type: amendment and supplement to the Bonytail, Humpback chub, Colorado pikeminnow, and Razorback sucker Recovery Plans.
• Copyright Material: NO

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EXECUTIVE SUMMARY
This document is the Lower Colorado River Management Plan (LCRMP) for big-
riverfishes and presents the strategies needed to recover and manage these
species in the lower basin. These management strategies are intended to
contribute to and assist with basin wide recovery of these fishes, and to their
eventual down- and de-listing. This document was prepared by a team
appointed in 1999 by the Regional Director of the U.S. Fish and Wildlife Service,
Region 2. It supplements the existing recovery plans for the federally
endangered bonytail (Gila elegans), Colorado pikeminnow (Ptychocheilus
lucius), humpback chub (Gila cypha), and razorback sucker (Xyrauchen texanus)
and their recovery goals. The LCRMP includes the mainstem Colorado River
and its tributaries from Lees Ferry to the Southerly International Boundary with
Mexico and is divided into six subunits: Grand Canyon, Lake Mead, Lake
Mohave, Lake Havasu, Parker-Imperial, and the Gila River basin.
The LCRMP will maintain genetic refugia for razorback sucker and bonytail and
establish self-sustaining populations of these species in the lower basin. In
addition, the plan calls for maintenance of the current humpback chub population
size with no decline in numbers and maintenance of an experimental
nonessential population of Colorado pikeminnow in the lower basin. These
ideas build on ongoing efforts in the lower basin that have prevented the
extirpation of existing populations and developed habitat and life history
information on these species. The management actions presented are believed
to be the most likely to enable the survival, reestablishment, and stabilization of
big-river fish populations in the lower basin. The plan will achieve this through
maintaining several inter-related large populations in a spectrum of habitat types.
These objectives will be accomplished using three strategies: 1) the use of
hatcheries to produce larger fish for reintroduction, 2) the use of natural or
constructed habitats to develop self-sustaining populations and to produce larger
fish for the mainstem habitat; and 3) the exploitation of habitats made available
by reservoir drawdown or drying to establish populations of large adults. These
strategies will necessarily include genetic, habitat, and population management
components.
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