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. . Although more fish were collected in Stratum X than other strata (Figure 2), electrofishing data (more effective for larger fish) indicated the upper two strata (V and W) supported greater numbers of large native species, including flannelmouth and blue- head suckers (Catostomus discobolis), and roundtail chubs (Gila robusta). Catch per effort data for seines generally reflected an abundance of the smaller species or young fish of larger species and generally support the total numbers data. Adult fish were collected primarily from shoreline habitat, while backwaters contained the largest number of young fish (Figure 3).. The relative abundance of individual species (catCh/effort) varied with life history stage and strata, reflecting the habitat preference and availability to fishes in each strata. In comparing the abundance of native and exotic fish species, Strata V, W, and X supported higher percentages of native species (87%, 90% and 69%, respectively). Although the explanation for this is unknown, this could result from habitat differences favoring the adaptations of native species over those of the exotics. A total of 58 Colorado sQuawfish were collected in all samples, 1980-81, of which 39 (2 recaptures) were adults (408 mm + TL) and 18 were juveniles (116-400 mm TL). Colorado sQuawfish were collected from all strata (V=l, W=5, x=8, Y=ll, Z=33). Adult Colorado squawfish were primarily collected from eddy (40%) and shoreline (28%) habitat. Substrate at point of collection was dominated by sand (55%) and silt (22.5%). Juveniles were found in slower moving waters, mainly from backwaters or eddies. Larval samples were collected in each stratum from 22 to 29 July, 1981. Although these samples have not been completely analyzed, no Colorado sQuawfish.;Larvae were identified (Snyder 1982). The significance of these results are unknown and should be related to the low flow conditions in the White River in 1981 and the existence of a possible drift mechanism for larvae (Miller et al. 1982.). % ~~~ In 1980, we reported the movement of a radiotelemetered Colorado sQuawfish between the Green and White rivers (Tyus et al. 1981 A). Nine adult Colorado sQuawfish were captured in the White River in 1981 and implanted with radiotransmitters. Although contact was difficult to maintain, two fish were monitored for 4 and 5 months, respectively. One was relatively sedentary and the other highly mobile. The mobile fish moved from the White River into the lower Green River and returned back into the White, travel- ing 611 km from 29 May to 7 October when contact was lost. ..: :'t, The occurrence of fishes found in this study was generally similar to those reported by other investigators (Lanigan and Berry 1981, Crosby 1975, Prewitt et al. 1977, and Wick 1981). The number 46 -~