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*****DRAFT***** time, age-0 (young-of-the-year) Colorado squawfish have commonly grown to the post-larval stage of development and are large enough that they can be captured by seines. The sampling procedure is essentially the same as that described above for larval collections, except that the amount of area swept by each haul of the seine is measured. This allows us to estimate the relative density of the fishes captured on the basis of the amount of area sampled. In 1982, all fishes captured as part of this field program were identifed in the field and released; however, in 1983--a year when the age-0 squawfish were particularly small--it became evident to us that accurate identilFication of these and other small fishes in the field was particuiarly difficult. In 1983 we began to preserve all fishes collected in the field; these preserved samples were identified later in the laboratory using a binocular dissecting scope. Summary of Captures ~- - Larval Colorado squawfish During the three years of our investigation, 31 larval squawfish were collected from the 15-mile Colorado River reaches immediately upstream and downstream from the confluence with the Gunnison River (Table 1). Although the amount of sampling effort was similar in the two river reaches, only 2 (6%) of the larvae were collected from the upstream reach, larval Colorado squawfish hatch from the egg when they are about 7 mm TL. The fins of larval squawfish do not begin to develop until the fish are 8-13 mm TL, and full development of fins (necessary for active swimming) does not occur until the larvae are 15-24 mm TL (Snyder, 1981). •Nbst of the larval Colorado squawfish that we collected were not large enough to have fully developed fins (Table 1). It is probable that many of these larvae were collected from very near the site where 3