WSP06389

• File Number: 8220.102.01.I
• Description: Aspinall ‎(AKA Curecanti)‎
• State: CO
• Basin: Gunnison
• Water Division: 4
• Date: 1/1/1994
• Title: Scopes of Work - Endangered Fish Program as Related to Aspinall
• Water Supply Pro - Doc Type: Report/Study

DOW FT COLLINS

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3) To determine the effeee of flow manipulation And habitat availAbility
upon growing season and size of Colorado squawfish young-of'eh~.year as
it relates to potential overwinter survival.

End Produet:

Completion oC the above objeetives will provide the necessary baseline
information to evaluate the contribution toward reproductive success of
the species by flow regime manipulation in the Gunnison River called for
under the Aspinall Scope of Work. The report will also provide results
and racollllll8ndAtJons concerning th.. stlLtus end problema of roproduction.
survival, and recruitment within the stock of Colorado aquawfiah in
occupied habitat within Colorado and Utah.

IV. Study area

Colorado III vor:

RK 298 to 206

V. Study MethodS/ApproAch

Task 1:
Colorado
lIlaiMtem
to 1996;

To determIne the relative abundance or population size of
squawfish larvae produced by existing wild adults in the upper
Colorado and Gunnison rivers within Colorado annually frolll 1992
relate to annual flow and temparature variables in both rivers.

Evaluation of spawning areas and production of Colorado squawflsh
larvae within occupied habitat in the Colorado liver would be evaluated
using drlft-net sampling in five locations. Thes. stationa would
include two sites on the Colorado, one above the Gunniaon confluence to
eaaple the "IS-milo reach. and one at Loma 29 km downatream to .ample
the "18.mila reach.; two aitea on the Gunni80n, one above the confluence
but below R~dlands DIversion and one above the div~rsion: and a fifth
8ite between Black Rocka and Weatwater Canyon in Utah. Potential or
confirmed apawning areal located within the occupied reach will be
evallUotad on the banis of ma51\itVode and timinr. of Colot:lLdo aquawHah
larvae captured in drift-neta between aites in Colorado and Utah,
existing information on larval fiah captures from the USFWS in Crand
Junction, and ongoing atudies related to spawnIng of Colorado squawfish
that will be conducted for the Aspinall Section 7 biological opinion.
Daily catch-per-effort indlcee would alao be oxamined among atatlons to
evaluate tho dogroo of downatre.. tranaport of these larvee out of this
reach.
Drift-net aampling would be repliceted at eech site. Sampling
would be done simultaneoualy at each aite, and would be conductad daily
at dawn throughout the month of July. Sampling at tho site between
BlacK Roeke and Westwater Canyon would be conductr.d by Utah DWR.
Samplea would be field proceaaed and prepared for taxonomic
identification and enumeration by apeclcs by CSU Larval Fish Lab at Fort
Collina. Colorado squawfiah larvae collected would be processed for
length, age determination. and eatlmated spswning date.

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