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6 I I 'i '. I a I I, I I I I I I I \1 'I I I and 40 m at its greatest width with 1.3-m maximum depth and each pool was similar to other baseflow refugia pools in each reach. Each pool was isolated with block nets at up- and downstream margins to prevent fish escapement and only fish longer than 90 mm were captured due to the dipnet mesh size. We sampled each site by depletion with four electrofishing passes. Time required for successive pass was 60 min, 40 min, 40 min, and 30 min at the upstream site and 30 min, 25 min, 25 min, and 20 min at the downstream site, but the area of each site was uniformly covered on each sample pass and subsequent passes required less time due to decreasing number of fish captured and handled. If an adequate number of individuals of a species were captured, then abundance estimates were calculated for each pool using removal model Mbh (White et al. 1 982). Results from depletion sampling were compared with those using other techniques in all reaches and with results using similar techniques at the same upper site in 1994. Spawning by a particular species within the Little Snake River was confirmed by collection of larvae. Fish of uncertain identity were anaesthetized and overdosed with tricaine ltrade name Finquel@) and preserved in 10% formalin. Preserved specimens were later transferred to 3% buffered formalin, identified, and cataloged at the Larval Fish Laboratory, Colorado State University under catalog numbers LFL-72444 - LFL-73992. Juvenile and adult Gila species were identified as humpback chub or roundtail chub (G. robusta) based on meristic and morphometric characters described by Snyder (1981) and Douglas et al. (1989). Small specimens of Gila less than 50-mm total length were preserved and identified at the Larval Fish Laboratory.