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11 b. Maybel1 to Sunbeam (RK 129-113). c. Cross Mtn. to Lily Park (RK 87-79). 2. Colorado River a. Loma to State1ine (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 1990. 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 e1ectrofishing 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 game fish 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 1990. 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 sectivn, the first suitable backwater encountered was sampled. This backwater was defined as a primary backwater if it was at least 30m2 in surface area and at least 0.3 m deep at its deepest point. The primary backwater was sampled with two, non-overlapping seine hauls. The sampling crew continued to travel downstream until a second suitable backwater was located within the 8 km section. Defined as the secondary backwater, it was sampled in the same manner. If no secondary backwater was found prior to the end of the 8 km section, no additional sampling was done. This sampling procedure was repeated in each 8 km reach. All Colorado squawfish large enough to reliably identify in the field were measured for total length, counted and released alive. In the primary backwater samples, all fish specimens were identified and counted. Fish too small to reliably identify in the field were preserved and subsequently identified in the laboratory. Samples from secondary backwaters were preserved after releasing all Colorado squawfish that could be reliably identified. These samples were searched for small Colorado squawfish in the laboratory. Species identification and counting for all fall seine samples was performed under contract by the CSU Larval Fish Laboratory in Fort Collins. The fall monitoring program has been conducted annually since 1986. The data collected from the above sampling procedures was computerized in a standardized database structure in DBase 111+ using standardized fields and codes. This is accomplished by either CDOW Northwest Region fisheries personnel or FWS-Grand Junction personnel. The data files are subsequently entered into in a centralized database maintained by FWS-Grand Junction. The