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I I I I I I I I I I I I I I I I I I I As discharge declined in the Little Snake River, diel water temperature variability increased. On July 13, when discharge dropped below 0.03 m3/sec on the Little Snake River, the difference between the daily high and low temperatures was almost 20oC. On the same date, Yampa River discharge was 4.5 m3/sec and diel water temperature variation was only 40C (Appendix Figure B.3). Hourly water temperatures cycled daily from a low just before sunrise to a high a few hours before sunset. Fish Community Each site and discharge level presented different obstacles to effective sampling and required different sampling gear, especially during the extremely low baseflow. For example, a shallow rapid located downstream of the boat launch made the lower site accessible only by raft even during runoff. The site was accessible only by foot during baseflow because discharge was too low for any type of boat. We sampled the site at both flow levels with trammel net, seine, cast net, and angling. The middle site was too shallow for a boat at all flow levels, and the monotonous habitat contained no suitable sites for large-fish sampling gear so we sampled it only by seine at all flow levels. The upper site was the only site sampled by electrofishing boat and seine during runoff; at low flow, it was sampled by bank electrofisher and seine. Because such different effort and gear were used at each site we did not compare fish captures between sites or seasons. Catch per effort was not calculated because different gear were used at each site and season and because catch varied greatly depending on the habitat and sampling efficiency. Attempts to standardize catch rates by effort would therefore be misleading so we combined all sites, sample gear, and sample trips and reported the total number of each species by life stage. 12