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3-7 Distribution Of YOY. The longitudinal distribution of YOY Colorado squawfish is examined monthly for three major regions (Table 3-4) and for 15 river reaches of 4 to 5 miles each (Table 3-5). From this analysis, it is apparent that the majority of the yay were caught in the Green River above the confluence with the Colorado River (67.78%). Fewer numbers were caught in Cataract Canyon (29.86%), while 12 yay were found in lake Powell (2.36%). Of the 15 river reaches examined, the yay appeared to be sporadically distributed in the lower 45 miles of the Green River, but the greatest numbers occurred between RM lO-15 (25.25%). In Cataract Canyon, few yay were found in the upper rapi ds (6.76%) and none were found in the lower rapids. The majority were found in a quiet section of Cataract Canyon from Y-Canyon/Cross Canyon through Cataract lake (l8.49%). The majority of these yay captured in Cataract lake were caught in July, when the fish were still young and probably near the areas in which they hatched. Sympatric Species. Field biologists who have encountered great numbers of nonnative fishes while seining for yay Colorado squawfish cannot help but wonder if competition and predation exist that impose added stress on the endangered species. Such interactions are difficult to assess afield. Nevertheless, the presence of large numbers of red shiners, channel catfish, and fathead minnows in sympatry with young squawfi sh strongly suggests interspecies interactions. Figure 4 is presented to illustrate the relative numbers (no./10'm2) of the three most numerous species found with young squawfish in seine hauls in five different habitats. The highest densities of YOY squawfish occurred in isolated pools (2.14) and backwaters (l.87). Most of the squawfish in isolated pools were found in Cataract Canyon where they would have eventually died from oxygen starvation and desiccation. This is a disturbing statistic that was also reported by Haynes (report presented to the Upper Colorado River Researchers Meeting in Grand Junction, Colorado, February 6-7, 1985) for the lower Yampa River in the proximity of squawfish spawni ng sites.