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. sampling than during the June sampling, suggesting that seasonal movement from the White River occurs. This is supported by radiotelemetry data. Sampling effort and sample size were inadequate to determine seasonal changes in Colorado squawfish relative abundance or size distribution. We speculate lower catch rates recorded in September are the results of spawning migration by mature fish from the river in June and July and those fish had not returned to the White River by the time of the September sampling. The few Colorado squawfish captured after 1 July appeared to be immature fish, suggesting they remain in the river year-round. Water discharge from the White River in 1982 compared favorably with discharge recorded in 1980 and was considerably greater than 1981 discharge (Figure 11). Peak runoff in 1982 occurred during the last week of May and first week of June. River flows from July through September 1982 remained higher than was recorded in either of the two previous years. These greater summer and fall flows were considered to provide more optimum habitat for Colorado squawfish in the White River than was provided during the same period in 1980 or 1981. . . . . . . Intensive Sampling for Larval and YOY Colorado Squawfish Between 19 July and 1 August, 72 combined drift net collections were made at RM 50.6 and 49 at RM 22.9 Accumulation of debris in the drift nets limited their effective fishing time. Although the nets were fished for one-hour periods, they were probably not efficiently fishing for more than 10 to 15 minutes. The large amount of debris made it time-consuming . . . 21 .