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Roundtail chub over 200mm in length consume a greater variety of prey items. Adult roundtail chub have been reported to feed on filamentous algae, aquatic invertebrates, terrestrial invertebrates (especially grasshoppers and ants), fish, and plant debris (Vanicek and Kramer 1969; Joseph et al. 1977). Minckley (1973) indicates that adult roundtail chub may also consume their own eggs as well as eggs of other fish species. Olson (1967) reported that the diet of roundtail chub in Navajo Reservoir was primarily plankton with some aquatic insects. Greger and Deacon (1988) determined that the diet of Virgin River roundtail chubs consists mostly of filamentous algae with some macro invertebrates. Macroinvertebrates were consumed primarily during December. At present, there is concern regarding the status of roundtail chub in the Colorado River drainage. Historically, the roundtail chub may have been the most abundant carnivore in the upper Colorado River Basin (Holden and Stalnaker 1975). Recently, a decrease in distribution and abundance has been documented at several locations (Vanicek et al. 1970; Joseph et al. 1977; Kaeding et al. 1990). Joseph et al. (1977) suggested that round tail chub populations often declined after predatory nonnative fish became established in roundtaiJ chub habitat. It is likely that both native and nonnative predators prey on roundtail chub. Joseph et al (1977) speculated that before the introduction of nonnative fish the roundtail was probably a major prey item for Colorado pikeminnow. The speckled dace is native to the Colorado River Basin and its tributaries. This species occurs in the mainstem and most medium to small tributaries. Holden and Stalnaker (1975) found the speckled dace common at most sites in the upper Colorado River Basin; however, this species was absent or rare in slower moving sections of the warmer, large rivers. This fish does, however, occur in larger rivers in areas of suitable habitat. Vanicek and Kramer (1969) found speckled dace common in collections from the Green River in Dinosaur National Monument. In medium to small tributaries, speckled dace occur in most habitats, but are usually most abundant in areas of current or riffle habitat (Holden and Stalnaker 1975). Carlson et al. (1979) indicated that speckled dace in the Yampa River were found in a variety of habitats including pools, backwaters and near shore habitat. During periods of low flow in the Yampa River, speckled dace survived for several days in stranded pools where temperatures exceeded 300 C. The speckled dace feeds primarily along the bottom, but will occasionally consume items in the drift. The diet of specked dace is almost entirely aquatic invertebrates; however, they may also rarely consume algae and detritus (Sublette et al. 1990). Speckled dace feed mostly at night. 35