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., '' INTRODUCTION. In April 1990, the Utah Division of Wildlife Resources (UDWR), the United States Bureau of Reclamation (BOR) and the United States Fish and Wildlife Service (FWS) launched a cooperative effort to capture razorback suckers from Lake Powell, Utah. Previous sampling efforts by BOR and UDWR in the spring of 1987 and 1988 showed that concentrations of razorbacks occurred in the San Juan arm (SJA)~of Lake Powell at Paiute Farms marina and in the Dirty Devil arm of Lake Powell. The cooperative effort in 1990 focused on these two areas. In light of the apparent lack of recruitment of razorback suckers in the reservoir populations, captured fish were removed from the reservoir and transported to a fish holding facility at Ouray National Wildlife Refuge. These fish are being held for future broodstock development and genetic comparison with fish taken from Lake Mojave, Arizona and Upper Green River razorback sucker populations. Water levels in the reservoir were similar during sampling sessions in April of 1987 and 1988 at 3684.45 feet and 3681.69 feet respectively. The reservoir level during the 1990 sampling, however, was 3650.87 feet. At the 1990 level, previous razorback capture sites were no longer inundated by the reservoir. In the San Juan arm, the reservoir extended only to a point 3.4 miles downstream from the old Paiute Farms marina boat ramps where razorbacks were captured in 1987 and 1988. As a result, the San Juan arm was accessed via Copper Canyon approximately 8 miles downstream from the Paiute Farms marina. Reservoir access to the Dirty Devil arm was still available at the Hite boat ramp in 1990. METHODS. An electrofishing boat supplied by BOR was used in addition to trammel nets to capture razorbacks in the vicinity of the Dirty Devil arm. An 8 foot sandstone ledge at reservoir edge at Copper Canyon prevented launching of an electrofishing boat to sample the San Juan arm. Trammel nets were used exclusively in this area. Nets were set and checked with a 16 foot inflatable AVON work boat powered with a 40 hp Mariner outboard motor, or with an 18 foot aluminum jon boat powered by a 25 hp Johnson outboard. Trammel nets varied in length from 50 feet to 300 feet and mesh sizes ranged from 1.25 inch to 2 inch inner mesh and 10 inch to 11 inch outer mesh. All were 6 feet wide multifilament sinking nets. Five to 7 nets were set during the day and checked every 1 to 3 hours. A 5 x 8 x 6 foot nylon mesh live pen supported by a floating frame of 4 inch diameter PVC pipe was used to hold fish before transporting. A 3/4 ton truck mounted with a 250 gallon fish distribution tank equipped with oxygen stones and a fresh-flow