3118

• UCREFRP Catalog Number: 3118
• Author: Wick, E. J. and D. Snyder
• Title: Abstract
• USFW Year: 1979
• USFW - Doc Type: Colorado Division Of Wildlife's Colorado Squawfish and Humpback Chub Trend Zone Monitoring Program.
• Copyright Material: YES

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St'\.J'-{ 'The Colorado Division of Wildlife's Colorado
chub trend zone monitoring program.

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squawfish apq Rympback

Ed Wick and Darrel Snyder, Colorado State University Larval Fish
Laboratory; Tom Lytle, Colorado Division of Wildlife, Grand Junction:
and Charles Haynes, Colorado Division of Wildlife, Fort Collins.

Abstract--In July 1977 the Colorado Division of Wildlife began
sampling five upper Colorado River trend zones to monitor the distribt:
and status of two endangered fish species. Study areas are: Yampa
River from Maybell to Sunbeam plus special sites at Juniper Springs,
Cross Mountain Canyon, and Lily Park; White River from Rio Blanco Lak
to County Road 65 Bridge; Colorado River from Palisade to the old
Clifton Bridge; Gunnison River from Whitewater to Redlands Diversion
Dam and Colorado River from Lorna to the Colorado Utah State Line.
Generalized habitat types are identified, at each collection site
and sampled,as independently as possible. Fishes are collected prima.'
by seine, dipnet, and electrofishing. Hook and line has proven effec:
at times for squawfish and humpback chubs. Percent composition for
each species is tabulated by size, habitat type, sampling site and
entire trend zone for all fish collected. A major objective of the
study is directed toward determining habitat preferences of the early
life-history stages and documenting reproductive success of endangere(
fish species. On 24 August 1979, two 19mm (TL) Colorado squawfish
(Ptychocheilus lllcius) and one 79mm yearling were collected 2km
above Black Rocks in Ruby Canyon, indicating limited reproductive
success in the area for two successive years. Two yearling humpback
chubs, (GiJ~ cvpha) 99 and ll3mm were collected in Black Rocks in
August, 1979, indicating recent reproductive success for that species
also. Beginning in 1979 an endangered fish tagging program, coordinat
by the USFWS, was incorporated into the study. On the Yampa River
trend zone,' 14 Colorado sC]llawfish and one humpback sucker (Xyrauchen
t~xanus) were tagged. On the lower Colo~ado River trend zone 29 squav
and 66 humpback chubs were tagged. The majority of these fish were
captured in the Black Rocks area in Ruby Canyon.

Pister, E. P. (Editor). 1979. Proceedings
council, Volume XI. NPS Headquarters,
Death Valley National Monument.

of the desert fishes
Furnace Creek,

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