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Despite the presence of adult squawfish in the 15-mile reach during the spawning seasons of 1986 and 1987, successful reproduction may have not occurred there then. No larvae were collected there during either year of our intensive sampling program. However, two larvae were collected there in 1982. Successful spawning in the 15-mile reach may only occur during infrequent years. Colorado squawfish larvae and YOY were collected 6-8 miles downstream from the 15-mile reach (in the lower 18-mile reach) in 1986 and 1987, as well as in 1983, 1984 and 1985 (Archer et al. 1985). During each of these years, as many as 23 larvae were collected between RM 162.7 and 164.8 (Walker Wildlife Area), as well as from other downstream sites. The one larva collected in fall 1987 was found 0.5 miles (M 162.7) downstream from the site, a location to which a radio-tagged adult from the 15-mile reach had briefly moved to during the estimated spawning period. Interestingly, the only year when larvae were collected from the 15-mile reach (1982) was also the only year they were not collected from the lower 18-mile reach. It may be that Color- ado squawfish spawn at various sites within the Grand Valley; the site(s) selected might depend on conditions that vary from year to year. Perhaps individuals return to areas where they have spawned before, and, if condi- tions are found to no longer be suitable, the fish select a different site. The collection of a larva from the lower Gunnison River in 1986, the first year that reach was sampled, indicates that spawning may occur there. It is possible, however, that this larva drifted downstream from the reach of the Gunnison above the dam. The movement of a radio-tagged, adult squawfish to the Price Stub Dam during the spawning period in 1986, as well as the similar movement of a fish to the base of Redlands Dam during the spawning 19