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t <br />Distribution of larval fishes was determined by seining river backwaters <br />from mid-July through the end of August. The river was subdivided into 2- <br />mile reaches; once weekly, backwater, embayment or shoreline habitat from <br />each reach was sampled using 0.5-mm-mesh hand seines. Captured fish were <br />preserved in 10% formalin and identified by the Colorado State University <br />Larval Fish Laboratory. Sampling effort was not constant among samples <br />within a given year, but average effort per sample was similar among <br />years. The area sampled included the aforementioned 15-mile-reach, the <br />adjacent 18-mile segment of Colorado River immediately downstream, and the <br />lower 2.2 miles of the Gunnison River between the Redlands Diversion Dam <br />and the confluence. <br />Distribution and relative abundance of young-of-the-year (YOY) Colorado <br />squawfish were estimated by seining backwaters with 3-mm-mesh beach <br />seines. Each year, two samples were collected from each of two backwaters <br />in each 5-mile reach. The 1986 effort was conducted on 22 September and 1 <br />October; in 1987, on 22 and 23 September; the 1988 effort, on 20 and 22 <br />September. Collected fish were preserved in 10% formalin in the field and <br />identified in the laboratory. To determine relative abundance of squaw- <br />fish and other species, the surface area seined was measured and the <br />number of individuals of each species collected per 100 square meters was <br />calculated. The study area sampled for YOY included the 15-mile reach and <br />the adjacent 18-mile segment of the Colorado River immediately downstream. <br />Habitat use by adult Colorado squawfish and razorback sucker was estimated <br />by visually categorizing the habitat type at the locations of radio-tagged <br />fish (e.g. pool, eddy, riffle, etc.). We divided riverine habitat used by <br />adults into eight major categories, the definitions of which are given in <br />6 <br />1