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observation, 14 were selected for sampling of water quality and fish communities. The five that were ultimately selected as study sites are located on the north side of the Colorado River along a 10-mile stretch from the new Redlands bridge in Grand Junction to about a mile west of the town of Fruita. From east to west, these are Terry,. Fish Chalet, T + F, Island, and Pabco ponds. These range from 0.85 to 3.16 hectares in size and from 1.7 to 3.7 m in mean depth. Although Island Pond was used during the first stocking season, it was dropped as a study site in June, 1984, after spring floods destroyed its dikes. 2. Bass and forage fish Bass age structure and population size varied not only between ponds but also between the 1983 and 1984 summer seasons. Fish Chalet Pond did not contain any bass during either season (Tables 1 and 2). Pelative densities of predacious fish, including bass, were high during both seasons in Terry Pond; mid during the first season in Island and Pabco ponds; high during the second season in Pabco; and low during both seasons in T + F and Fish Chalet (Tables 5, 6, and 7). Forage fish abundance also varied between ponds and years (Tables 3 and 4). Terry Pond had comparatively low numbers during both years with the predominate small fish being green sunfish during 1983 and Young-of-the-year MY) largemouth bass during 1984. Island Pond also contained low numbers of forage-sized fish, with red shiners being the predominate species. The number of forage fish in Pabco Pond during 1984 was less than half what it was in 1983 due to the almost complete disappearance of the formerly abundant mosquitofish. T + F Pond had the highest densities of forage fish during both years, with numbers of the dominate fathead minnow and red shiner being in 1984 double what they were in 1983. Young-of-the-year carp were the sole forage fish in Fish Chalet Pond, and their numbers were consid- erably higher in 1984 than in 1983• 3. Limnology All five ponds froze over during December, 1983, and did not thaw .until the end of March, 1984. Then, in the middle of May, high runoff caused the river to flood its banks and four of the five ponds temporarily became Colorado River backwaters. Fish Chalet Pond alone, protected by a high dike, remained isolated from the river during the duration of the flood. By the first week of July, the river level had dropped to the point where three of the four flooded ponds had again become isolated from the river. The dikes of Island pond had been deeply eroded however, and thus reisolation for that pond never occurred. Seasonal changes in water temperature were similar among ponds, with the exception of Fish Chalet having an earlier and more gradual rise during spring due to it not being influenced by the cool river flood waters (Figure 1). Dissolved oxygen (DO) varied greatly between seasons in all the ponds; the lows occurring during Febuary and July. Although bottom DO levels fell to as low as 1 ppm in three of the ponds, surface DO levels were always suitable for maintenance of fish 3