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2. Eddy (4 collections) a. deep (2) b. shallow (2) 3. Shoreline (6 collections) a. vegetation (2) b. gravel/cobble (2) C. sand/silt (2) Larval collections were made in late July 1981 and sent to the Larval Fish Laboratory, Colorado State University for sorting and iden- tification. Beginning in September,,YOY collections for the larger Colorado squawfish were made using the same sampling design, with the exception that fishes were identified in the field and `a one-quarter inch mesh seine was used for all collections. Movements, Habitat Preference and Spawning of Colorado Squawfish During the spring of 1980, extensive sampling was conducted in the Green River near the confluence of the White to collect Colorado squaw- fish for use in radiotelemetry studies. It is emphasized that these collections were biased in favor of obtaining Colorado squawfish from habitats where they were most abundant. Although cold weather made it difficult to collect fish, the collections began in March so that the fish might recover from the surgery before the spawning season Collec- tions were initiated using trammel nets and electrofishing gear; however, trammel nets were discontinued because of manpower shortages and a lack of success. Colorado squawfish (TL 508-707 mm) were captured by electrofishing in the Green River. Fish were anesthetized with MS 222 and `surgically implanted with radiotransmitters immediately after capture. Surgical procedure was similar to Bidgood (1980) except for several departures; sutures were individual (usually five) rather than the continuous suture used by Bidgood and the incision was made laterally, immediately anterior and slightly dorsal to the insertion of the right pelvic fin. Suture knots were coated with "Krazy Glue" (Bill Loudemilk, letter o the U.S. Fish and Wildlife Service, March 27, 1980). Surgical implantation was completed with'AVM fish modules (AVM 1979) dipped in melted beeswax. These transmitters (Sm-1) weighed approximately 11 g and are of "padlock" shape. The units are powered by a mercury (HG-630) battery and have a theoretical life of about 215 days. The units transmitted in the 40.660-40.700 MHz frequency range. Radio receiver sets used were Smith-Root RF-40 and SR-40 models. The RF type enables the investigator to identify any particular frequency transmitted in the 40 MHz range. The SR receiver is a "search" type and will pick up all emitted frequencies in the range. Omni-directional and directional type antennas were employed. A Larson-Kulrod whip antenna was used to search for implant fish. 'This antenna was mounted on a 20 cm square steel plate elevated about 4 m 14.