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apidly ~igested by predators. No comprehensive study of predation on larval Colorado squawfish has been published, but work in progress in the Green River will address this problem (i.e. Flaming Gorge Studies, a cooperative project between BR and FWS). Post larvae- Colorado squawfish attain a length of 40-50 mm in the first year of growth. It is assumed that at about this size, the fish becomes more predaceous, eating more smaller fish. It is also possible that the fish could experience better growth in backwater habitats that are full of small introduced minnows. But until this size is reached, lab studies indicate that the postlarvae may be at a disadvantage with many of the small, introduced species, and may be prey for some of the larger fishes that can still enter backwaters (Karp and Tyus (1989)). Juveniles- Little is known about the life of juvenile Colorado squawfish. These fish are large enough to freely navigate the main river channels, and presumably do so. There are possible advantages and disadvantages to this fish from introduced farms; the squawfish eating smaller forms and being eaten by larger ones until growth to an adult size occurs. Adults- There are some indications (D. S. Schultz, personal communication) that growth of adult fish may be better now than under historic conditions. This is presumably due to a larger. prey base. However, same prey may be lethal, as indicated by the choking of ,. large Colorado squawfish on smaller channel catfish (McAda 1984, Pimental et al. 1985, Vanicek 1967). Some of the largest fish introduced, including northern pike, and walleye, are potential 33