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light traps, and drift nets. Multiple fish collection techniques were used in order to sample the entire fish community, and most techniques were used throughout the study reach. Occasionally, trammel nets were set as far up stream as 1.25 miles above Grassy Trail Creek. In 1997, fish were collected from Apri121 to September 17. Sampling vras again confined to the lower 48.75 river miles (Figure 2), except for one day of sampling in a pool located below Farnham Diversion (river mile 88.5). Boat electrofishing, trammel nets, and the seine were deployed on a monthly basis each year. Drift nets and hoop nets were used sporadically each year. Backpack electrofishing, minnow traps, and light traps were not used during 1997 due to their poor efficiency in 1996 and higher water conditions observed in 1997. Higher water levels in 1997 also limited the amount of data collected with the seine, hoop net, and drift nets. Boat electrofishing was conducted from a plastic canoe operated by two people. Initially, all areas of the river were sampled, but it quickly became clear that nearly all of the fish were captured near the banks. Due to this observation, the banks were the only portion of the river sampled with boat-electrofishing gear after the first sampling trip. The person in the stern of the canoe steered the boat and controlled the electrofishing equipment. Current was produced by a gasoline-powered generator and controlled with a Coffelt VVP-15 electrofishing unit. A spherical cathode was used along with an anode consisting of three cable droppers. Voltage was varied in order to keep output current at approximately 6 amperes. The person in the bow of the canoe netted fish that were stunned by the electricity. All captured fish were held in a bucket of water until they could be measured to the nearest millimeter and weighed to the nearest gram. Colorado pikeminnow longer than 175 millimeters were also PIT tagged, and all fish were released after data collection was complete. Backpack electrofishing was attempted by a two person crew in 1996. One person carved a Coffelt Mark X electrofishing unit. Voltage was varied in order to keep the output current near 1 ampere. The second person netted fish and carried them in a bucket of water until they could be measured to the nearest millimeter, weighed to the nearest gram, and released. Due to poor sampling efficiency, this technique was only used one time. Trammel nets were used in runs that were at least two feet deep. Nets were anchored to shore or an island, and weighted to keep them on the bottom of the river. The nets were 75 feet long and six feet deep, with 12-inch square walls. Two mesh sizes were used. Some nets had one-half inch square mesh and others had one-inch square mesh. Half-inch-mesh nets rapidly filled with debris, so they were used less frequently than one-inch-mesh nets. Initially, nets were set overnight, but set time was later reduced to two hours in order to reduce fish mortality. All fish captured were measured, weighed, and released (if alive). Trammel nets were used more frequently in 1996 than in 1997 due to the habitat conditions present each year. Seining was done in low velocity areas. The seine was 13 feet long, 4 feet deep, and had 1/16-inch mesh. Captured fish were identified in the field when possible. A subsample of fish were measured, and all fish were released. If fish were too small or too numerous to be identified in the field, they were preserved in alcohol and transported to a laboratory for identification. Seining was done more often in 1996 than in 1997 due to more favorable habitat conditions for seining in 1996. A-two-foot diameter hoop net with'/z-inch square mesh was used in slow runs that were at Least 2 feet deep. The cod end of the net was anchored to the shore, and the mouth of the net was weighted to keep it on the bottom. The net also had wings to direct fish toward the mouth of the net. Set times ranged from approximately 2 to 12 hours. All fish captured in the net were 4