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I I I I I I I I I I I I I I I I I I I 4-l 4.0 CONCLUSIONS 1. The presence of larval Colorado squawfish less than 25 mm TL in Cataract Canyon indicates that spawning probably occurs in or invnediately above the canyon; 2. Cataract Canyon meets two of the three criteria of a suspected spawning area for Colorado squawfish, according to the UCRBCC (l984) Report; larval squawfish less than 25 nm TL were found and deep pool s interspersed with cobble/riffle habitat, but no ripe males or aggregations of radiotagged adults were found (note that the UCRBCC already took the liberty of designating Cataract Canyon as a suspected spawning area when only two of the three criteria have ever been met). 3. Field investigations in 1985 began too late to capture spawning adul ts and the very small 1 arvae in or near the spawni ng sites; sampl i ng should have begun with drift nets by the last week of June. 4. YOY humpback chub and adults captured in Cataract Canyon indicate that this endangered species is also reproducing in or near the canyon 5. One suspected YOY bony tail and one suspected adult bony tail suggest that further investigations are needed in the area to assess the presence or absence of this species in this region of the Colorado River 6. YOY Colorado squawfish appear to be ending up in upper Lake Powell, but a paucity of habitat appears to be affecting their survival 7. Relatively high numbers of YOY Colorado squawfish in the lower 40 miles of the Green River indicate the presence of spawning in this region 8. It is unknown if the YOY squawfish captured in Cataract Canyon originated from within or drifted from the Green or Colorado Rivers further upstream; early warming water temperatures in Cataract Canyon (relative to the upper Green and the Yampa) and the size of the larave and juveniles indicate that spawning occurred within the canyon or immediately upstream