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both sides of the river. Sampling crews worked the river at least two days a week during intensive sampling in the spring. When electrofishing, all northern pike and other predators were captured during all samples. Other species were captured and counted in about one- half of the electrofishing efforts. Only northern pike or other predators were counted during trammel netting, but all species were identified and counted when fyke nets were used. All fish collected and identified in selected electrofishing collections were measured for total length (T'L, ± 1 cm) before release. Ali captured northern pike were measured (TL, f 1 cm) and removed from the river. In 1995, northern pike were held alive, picked up by the Colorado Division of Wildlife, and transported to Harvey Gap Reservoir. In 1996, all pike were humanely sacrificed, gutted, frozen, and given to the Division for distribution to local food banks. Date and location were recorded for each sampling effort. Sampling effort was recorded for all fyke net samples (total hours the net was set) and for about one-half of all electrofishing samples (seconds of shocking time). However, beginning and ending point (river kilometer) were recorded for all electrofishing collections. Sample effort was not recorded for trammel net collections. Mean catch per effort (CPUE) was calculated for all fyke net and electrofishing samples. Electrofishing CPUE for northern pike was calculated using kilometers of shoreline electrofished since that measurement was recorded for all electrofishing collections. Mean CPUE for other species was calculated using seconds (converted to hours) of shocking time for samples when all f sh observed were collected and counted. Mean CPUE for fyke net samples was calculated using hours that the net was set. Length-frequency distributions for northern pike and common sympatric species were also calculated. Because of the variety of gears used during different time periods, catch per effort was also calculated using 'crew-days' as a gross comparison among different gears, seasons, and years. One crew-day equaled effort expended by a two- or three-person crew during at least part of one day. In most cases, full days of sampling were expended by each crew (8-hr day, including 2 hr travel time). Crews usually used a single gear type for the whole day. However, occasionally two different gears were used (e.g. electrofishing after the fyke nets 5