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3 nighttime sampling of ictalurid predators. Food habit analyses were conducted on all centrarchid and ictalurid fish species captured. Drift net sampling was conducted concurrently to document presence/absence of Colorado squawfish larvae in the mainchannel. Job 3. Title: Northern pike habitat utilization Sampling of flooded tributary backwater habitat during pre-runoff and peak runoff periods was conducte4 in April-June 1991. This data was collected concurrent with sampling in Job 1. Data will include numbers of northern pike and channel catfish captured relative to abundance of Colorado squawfish and other fish species, and fish size frequency comparisons in each habitat type. Job 6. Title: Standardized monitoring surveys The Colorado Division of Wildlife has responsibility for the following tasks outlined in the monitoring schedule: A. Spring - Late juvenile/adult Colorado squawfish 1. Yampa River a. Above Juniper Springs (RK 169-153). b. Maybe1l to Sunbeam (RK 129-113). c. Cross Mtn. to Lily Park (RK 87-79). 2. Colorado River a. Loma to Stateline (RK 245-213). 3. White'River a. Below Kenney Reservoir (RK 169-153). B. Fall - Post-larval, Age-O Colorado squawfish 1. Colorado River a. Grand Junction to Ruby Canyon (RK 274-225). The spring monitoring schedule was conducted in April-May 1991 and 1992. Each river reach was divided into at least two sub-reaches to provide replicate samples. One shoreline of each subreach constituted one sample. Sampling was done by boat with electrofishing along both shorelines of all reaches. Sampling was done downstream at a steady pace with all habitat features being sampled once as they are encountered. Sampling time was measured to the nearest second with an elapsed time clock located on the variable voltage pulsator. All captured Colorado squawfish were measured for total length, weighed and noted for a color-coded and numbered Carlin tag. The fish were then released at the original capture site. Numbers of Colorado squawfish observed but not captured were recorded at the end of each sample. Total numbers of warmwater gamefish species observed during sampling were also noted at the end of each sample. The spring monitoring program has been conducted annually since 1986. The fall monitoring schedule was conducted in September 1991 and 1992. Sampling was conducted with a 3.2-mm ace mesh beach seine, 4.6 m long by 1.2 m deep. The river reach was divided into 8-km long sections. As the sampling crew progressed downstream in each section, the first suitable backwater encountered was sampled. This backwater was defined as a primary backwater if it was at