7740

• UCREFRP Catalog Number: 7740
• Author: McAda, C. W. and L. R. Kaeding.
• Title: Physical Changes in the Gunnison and Colorado Rivers Resulting from Construction of the Aspinall Unit and Related Projects, with Hypotheses to Assess the Effects on the Endangered Fishes
• USFW Year: 1991.
• USFW - Doc Type: Final Report.
• Copyright Material: NO

Reudi Dam, completed 1969. Colbran Project, Vega Reservoir, completed 1960.
Silt Project, Rifle Gap Dam, completed 1967. McPhee Reservoir was built on
the Dolores River (tributary to the Colorado River downstream. from the
Gunnison) in 1984.
Biolo i~ cal
Colorado squawfish
Historical information on the distribution of the endangered fishes in
the upper Colorado and Gunnison rivers is limited. Jordan (1891) reported
Colorado squawfish as common in the upper Colorado River. He also captured
some specimens from the Gunnison and Uncompaghre (tributary to the Gunnison)
rivers near Delta. Ellis (1914) collected fish from the Colorado and Gunnison
rivers near Grand Junction, but did not report any Colorado squawfish. The
next documented fish collections did not occur in the area until the 1940's
when Chamberlain (1946) reported Colorado squawfish from the lower Gunnison
River. Kidd (1977) reported that a commercial fisherman collected Colorado
squawfish from the Gunnison River near Delta from 1930 until 1950 (50 in 'one
of the better years'). Wiltizus (1978) believed that the Redlands Diversion
Dam reduced Colorado squawfish numbers in the Gunnison River by preventing
upstream movement from the Colorado River. However, Valdez et al. (1982a)
collected eight adult-size Colorado squawfish from the Gunnison River above
Redlands Dam. Osmundson and Kaeding (1989) collected one larval Colorado
squawfish just downstream from the Redlands Dam in 1986; it is not known
whether the larvae was spawned above or below the dam. Wick (personal
communication) believes that high-quality, adult Colorado squawfish habitat
still exists in the Gunnison River.
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