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In 1981, CRFP conducted a basin-wide standardized larval sampling program which was repeated in 1984 on the Green River. In 1982 the Vernal station carried out an intensive sampli?g of mid-channel drift mechanisms for Colorado squawfish. Sampling in 1983 was qualitative and directed towards confirming spawning sites and periods through the collection of relatively young fish that were considered recently emergent. Post larval young-of-the-year sampling was standardized between field stations except that 3x5 mm (1/8x3/l6 in) mesh seines were used in the Green River sampling whUe 3 rrrm.2 (1/8 in2) mesh seines were used on the Colorado River after 1982. The sampling designs were similar except that replications varied between stations and years depending upon manpower capabilities. Sampling was scheduled so post-larval fish were large enough for field identification but spawning occurred so late during 1983 and 84 that fish in the Colorado River were difficult to identify and therefore samples were preserved and later identified with binocular microscopes. Sampling generally occurred fram mid September to early November. The Vernal field station also conducted an early spring sample during 1984 to corroborate the previous fall sampling results. c/ Sampling was conducted under a systematic sampling design with a ran- danized start. Each river was partitioned into 5-mile reaches and the first backwater encountered was sampled along with an adjacent shoreline area. All Colorado squawfish captures were measured individually for total length (TL). Depth, velocity, substrate and total area sampled was also recorded for each collection. Catch/effort statistics were calculated. on the basis of captures per 10 m2 seined. Sampling reaches were river kilometer (RK) 35.4 (river m1 (RM) 22) to RK 555 (RM 345) on the Green River and the Green River confluence (RK 0) to RK 298 (RM 185) on the Colorado River. Information on the adult and juvenile Colorado squawfish population were gleaned primarUy through a number of other sampling activities which resulted in capture data that were useful for relative abundance and 4