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anodes (about 28-cm diameter) suspended from fiberglass booms from the bow of the boat and two 2.1-m long cathodes (0.64-cm diameter twisted stainless steel cable) suspended from each side of the boat. The boat hull was also used as a cathode in conjunction with the droppers. In 2000, wild Colorado pikeminnow were transferred from the river to the Horsethief State Wildlife Area (SWA) in early-June and held indoors in the "kettle" prior to being implanted with radio transmitters. There are six ponds at Horsethief SWA, fed by water pumped from the Colorado River, that hold endangered broodfish. The kettle is a concrete box structure, 1.2-m wide X 6.1-m long that also receives discharge water from the six, outside holding ponds. The kettle is 0.6-m deep and holds approximately 1,200 gallons of water. In mid-June 2000, five wild and five, 1991 year-class, sub-adult Colorado pikeminnow were surgically implanted with radio transmitters at Horsethief SWA. Four of the wild Colorado pikeminnow were collected from the 18-mile reach and one from the 15-mile reach. Following surgery, wild Colorado pikeminnow were held indoors in 1.2 m diameter, fiberglass, circular tanks (200-gallon capacity) at Horsethief SWA. The circular tanks were constantly fed with discharge water from the six outdoor ponds. The five 1991 year-class Colorado pdceminnow that were radio tagged were held in the kettle. Fish were held at Horsethief SWA for about 1 week prior to being transported and stocked in the Upper Colorado River near Parachute. An additional 55, 1991 year-class, sub- adult (mean TL=398 mm; range=358-451 mm) Colorado pikeminnow that were being held in one of the ponds at Horsethief SWA were also stocked in late-June 2000 near Parachute at either RM 223.0 or 227.6 (Appendix A). In 2001, 12 wild Colorado pdzeminnow were collected from the 18-mile reach and seven from the 15-mile reach. All 19 wild Colorado pikeminnow were radio tagged, transported, and stocked is the Upper Colorado River at Rulison, Colorado (RM 229.9), on the same day of their respective capture. In 2000, fish were either transported in a 225-gallon fiberglass tank or a 200- gallon aluminum tank. In 2001, fish were transported in a 75-gallon galvanized tank that was plastic-coated. During transit of both years, aerators were used, fish were provided oxygen, and 0.5% salt (by weight) was added to the water to assist the fish's osmoregulation (Carmichael et al. 2001). At the stocking site, transport water was tempered with river water. Both wild and domestic-reared Colorado pikeminnow stocked were marked with passive integrated transponder (PIT) tags. Capture and release locations and dates along with size statistics and individual transmitter codes for all Colorado pikeminnow radio tagged during 2000 and 2001 are provided in Appendix B. None of the radio-tagged fish were held as controls. 8