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I I I I I I I I I I I I I I I I I I I 5 caught were identified, enumerated, measured, and returned alive to the river. Fish over 200 mm were marked with individually numbered spaghetti tags. Rare fishes over 200 mm were marked with fingerling tags. Benthic macroinvertebrates were sampled with a modified Hess sampler at the three sites mentioned above. Three replicates were taken at each site in cobbled areas of similar depth. The samples were preserved in 70% ETOH and transferred to BIO/WEST's invertebrate laboratory in Logan, Utah, for analysis. The samples were sorted and identified to the lowest practical taxonomic level. Samples containing a large number of organisms were subsampled using a rotary subsampler. Plankton were sampled monthly at the same three sites. Twenty- five liters of water were filtered through a 80 u mesh plankton net and the contents preserved in 3% formalin. Three replicates were taken at each station. The samples were analyzed for species present and relative abundance of both zoo- and phytoplankton. Periphyton was also sampled monthly at each of the three stations by scraping rocks from one square foot of cobble substrate and pre- serving the contents in a 90% acetone solution. Three replicates were taken at each station and the samples were analyzed by the Utah Water Research Laboratory at Utah State University for chlorophyll a content. Aquatic macrophytes were visually noted during the sampling trips. Taxa present and their relative abundance were recorded.