7055

• UCREFRP Catalog Number: 7055
• Author: Archer, D. L., L. R. Kaeding and B. D. Burdick.
• Title: A Study of the Endangered Fishes of the Upper Colorado River.
• USFW Year: 1985.
• USFW - Doc Type: Grand Junction, Colorado.
• Copyright Material: NO

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2. FWS will develop a comprehensive Conservation Plan to serve as a
guide for managing the endangered fishes and their habitats in the
upper basin. An itemized list of costs incurred with plan
implementation will be included.

3. Costs of measures to avoid jeopardy resulting from water depletion
by projects subject to Section 7 consultation will be borne by
project sponsors. Conservation Plan costs will be apportioned among
sponsors according to the percentage of the remaining upper basin
waters physically available for development (under the terms of the
Colorado River Compact) that their respective projects would use.

The FWS assumed that adequate time and funding for research, facilities
construction, and habitat rehabilitation were available and that an effective
management program could be developed consistent with the Colorado River
Compact. The first biological opinion issued under this procedure was that
for the Windy Gap Project, sponsored by the MUnicipal Subdistrict, Northern
Colorado water Conservancy District (MS-NCWCO). Although hydrologic analyses
performed by FWS and BR indicated project operation would not result in
measurable changes in flow at downstream gages, the opinion prescribed
conservation measures for the endangered Colorado River fishes to compensate
for the unforeseen detrimental effects of the project that might occur. A
cooperative agreement and work plan were negotiated between MS-NCWCD and FWS'
and MS-NCWCD subsequently transferred $550,000 to FWS for research on the
endangered fishes. The intent of the agreement and work plan was to improve
our understanding of the ecology of Colorado squawfish and humpback chub in
the upper Colorado River; the factors that affect the early-life survival of
Colorado squawfish were considered especially important. Knowledge of these
limiting factors will allow FWS to identify ways to maintain and recover the
populations of these fishes. The specific objectives of the work plan are:

1. Locate and describe specific areas of squawfish and humpback chub
reproduction in the Grand Junction area.

2. Locate and quantify specific rearing areas for Colorado squawfish
and humpback chub.

3. Identify key factors influencing survival of progeny of squawfish
and humpback chub up to juvenile size.

4. Mbdify at least two backwaters and one gravel pit between the
upper end of De Beque Canyon and the confluence of the Colorado
and Green rivers as part of the habitat-manipulation effort.

5. Evaluate natural and modified backwater areas as habitat for
rearing of Colorado squawfish and humpback chub.

6. Determine extent of movement of Colorado River endangered fishes
with particular emphasis on any tributary movements.

The present report describes the results of these studies. The report is
divided into three segments: investigations of Colorado squawfish,
investigations of humpback chub, and an evaluation of non-flow management
techniques to maintain and recover the Colorado squawfish population. The