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the first day included time periods A-1, B-1, and. C-2, then sampling on • the second day would be done during periods A-2, B-2, and C-1. Sampling on the third day included the same periods as sampled on the first day. Data were recorded in the same manner as were other collections except all Colorado squawfish were fin-clipped before release. Table 5 Sampling periods used during diel sampling tor young Califonia squawfish A-1 A-2 B-1 B-2 C-1 C-2 !400 0400 0800 1200 1600 2000 24( Military time All habitat types found in proximity to a selected backwater were sampled with a 1/4-inch (0.6 centimeter) mesh seine at the same time with comparable effort. This allowed comparisons of the abundance of Colorado squawfish in backwaters with other habitat types. On October 9, 1980, the Vernal field office initiated a small study in cooperation with the Bureau of Reclamation and Fish and Wildlife Service (Division of Ecological Services). The objectives of this study were two: (1) to determine if peaking power type releases from Flaming Gorge Dam would have a measurable effect on backwater habitat (important for young Colorado squawfish) as far downriver as Ouray, Utah; and (2) to evaluate any potential effects on movement or habitat preferences of young Colorado squawfish. In order to monitor any effects a large backwater was selected at RM 255.4 (409 kilometers) in stratum F. Samples of fish populations were made as stated for the diel investigations. Depths and relative size of the backwater and depth of the river was recorded each time fish samples were taken. Noted effects were compared with the U.S. Geological Survey (USGS) stream discharge monitoring station at Jensen, Utah. Radiotelemetry of Colorado squawfish A radiotelemetry program was initiated at the Vernal station in March 1980. The objective of this work included an investigation of major movements, habitat preference, and spawning of Colorado squawfish. In addition to work done on the Colorado squawfish, observations were also made on one razorback sucker. During the spring of 1980, extensive sampling was conducted in strata E and F to collect Colorado squawfish 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 spawning season. Collections were initiated using trammel • nets and electrofishing gear; however, trammel nets were discontinued because of manpower shortages and a lack of success. Early efforts also included the use of larger seines. These efforts were also terminated because of manpower shortages. 15