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1 1 1 t into the river adjacent to the backwater. The non-acclimated suckers served as a control. We examined ifpre-release acclimation was able to affect the dispersal distance, dispersal rate, or behavioral patterns of razorback suckers following stocking, as well as examining the habitats that razorback suckers utilize within Canyonlands National Park. MATERIALS AND METHODS Sources and Transportation of Fish Thirty razorback suckers were obtained from the USFWS Ouray fish hatchery located near Vernal, Utah. The 30 fish were the progeny of 1 female and 2 males collected from the Green River at the Jensen site (River Kilometer[RK] 490; RK 0.0 is the confluence of the Green and Colorado Rivers). The suckers were the control group for a canceled chemoreception experiment. (Tom Pruitt, USFWS, personal communique). The razorback suckers were transported in a 2000-L tank with oxygen bubblers from the Ouray National Fish Hatchery to the Green River at Mineral Bottom (RK 84) on June 16, 1998. Fifteen fish were then transferred to 100-L Coleman coolers, lashed inside of a 5.5-m Achilles inflatable boat. Two transportation trips were made downstream to the release point at Millard Bottom backwater (RK 54). Two water changes were made during transport to maintain adequate oxygen levels during the 45 minute trip. Transmitter Attachment All suckers were measured (TLmm) and weight (g, Appendix 1), and had an Advanced Telemetry Systems (ATS©) 90-day radio transmitter attached. Each transmitter was verified to be functioning properly before being attached to a fish by removing the deactivation magnet and listening for a signal with the ATS receiver. Transmitters were 5.5 by 1.0 cm, outfitted with a beveled leading edge and a tapered rear cone, and attachment holes had been drilled through the epoxy. The holes were placed 1 /3 up from the bottom on both ends of the transmitter. Transmitters were sewn with 9-kg test monofilament line onto the midline of the suckers' dorsal keels directly above the pectoral fins. Each suture was inserted ~10 mm below the dorsal keel surface and three square knots held each transmitter firmly against the keel. Each transmitter trailed a 25- cm whip antenna made of very fine stainless steel wire. The whip antennae terminated 1 to 10 cm anterior to the upper lobe of the caudal fin. None of the whip antennae needed to be trimmed in order to avoid contact with the caudal fin. This external attachment method was modified from Mueller and Marsh (1998) and was designed to allow the fish to eventually "shed" the tag. Experiments in circular tanks showed that the monofilament sutures would be pushed to the dorsal keel surface and expelled by razorback suckers over time. A few fish shed their transmitter within the first month, but most fish retained their transmitters for two or more months. This method is 4 r