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. to locate and separate larval fish. No Colorado squawfish were identified from drift net collections. Four species of larval fish were captured by drift nets (Table 4). Flannelmouth (Catostomus latipinnis) and bluehead (Catostomus discobolus) suckers were the most abundant fish larvae taken, followed by speckled dace (Rhinichthys osculus) and then channel catfish (Ictalurus punctatus). Although some species differences were noted, drift netting was 1.75 times more effective in collecting larval fish during darkness than during daylight hours. Water temperatures when drift netting ranged from 20.6 C (69 F) to 27.8 C (82 F) and averaged 23.9 C (75 F). Miller et ale (1982b) reported Colorado squawfish spawning at water temperatures of 20 to 21 C (68 to 70 F) and hatching in 4 to 6 days at these temperatures. High temperatures recorded in the White River made it unlikely that drift netting was conducted too early to collect larval squawfish; however, Ed Wick (pers. comm., 1982, cnow) reported Colorado squawfish spawning in the Yampa River did not peak until the end of July; two to three weeks later than in 1981. Backwaters along the White River were hand seined in late July and in August to qualitatively collect larval fish throughout the 71.7-mi (115-km) ~tudy area. This sampling effort collected 1,752 larval fish representing seven species. Red shiner (Notropis lutrensis) was the predominant species taken from backwater areas, comprising 61 percent of the total catch. They were followed by speckled dace (16%), flannelmouth sucker (9%), roundtail chub (Gila robusta) (5%), bluehead sucker (4%), fathead minnow (Pimephales promelas) (3%), and channel catfish (<1%). Hand seining results differed from drift netting results in number of . . . . . . . . . 29 .