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FISHES Methods Collections Routine fish collections were made on July 10-12 and 18-20, August 6-8 and 26-28, and September 19, 1975; March 20, May 19-21, June 1-3 and 22-24, July 15-17, August. 4-6 and 16-19, and October 9-10, 1976; and April 22-23, May 25-27, June 27-28, July 27-31 and August 30-3T, T977. A canoe sampling trip between Station Y-2 and Juniper Springs Canyon above Y-3 was conducted on August 16-18, 1976. Fish were also taken about 10 km below W-A during a cooperative electrofishing trip with Colorado Division of 6Jild- life Biologists on August 26, 1976 (data were combined with 4J-A data). Additional trips were made during 1978 to collect endangered fishes and fish gametes. Procedures and techniques for fish collection were varied in accord- ance with water conditions to most efficiently sample fish communities. As experience was gained, procedures became more standardized. Electrofishing gear was used wherever suitable throughout the study, usually over deeper waters in pools and along banks, and occasionally in backwater areas. Electro- fishing equipment was mounted aboard a 4.8-m flat-bottomed boat fitted with two 3.3-m fiberglass booms. The booms held 1.5-m X 9.5-mm steel-cable elec- trodes, and 3.1-m X 9.5-mm cable electrodes were mounted in the middle of the boat. Power was supplied by a 3500-watt 60-cycle generator and modulated through a Coffelt Model VVP-3E variable voltage pulsator (VVP) cantrol box. Type and amount of current, frequency of pulse, and area of electrodes were varied depending on water conditions. High water conductivity dictated that ~ minimal electrode surface area (obtainable only by boom-to-boom operation) 35