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Powell. Twelve adult razorback sucker were captured in the San Juan -_ Arm of Lake Powell in March. Eight of those fish were males in repro- _ ductively ripe condition. Two Gila spp. specimens were collected from backwaters between 103-93 miles above Lake Powell. ~ Overall, the fish community of the San Juan River was dominated by flannelmouth sucker, carp and channel catfish. Backwater habitats were dominated by exotic species, primarily red shiner and fathead minnow. Carp and striped bass were the most numerous fishes in col- lections from the San Juan Arm of Lake Powell. ~ It is recommended that the Colorado River Fishes Recovery Team address future endangered fishes studies of the San Juan River. A committee such as the Recovery Team, in which the various agencies involved in endangered fishes management and recovery are represented, would be the logical entity to guide the integration of the San Juan ~ River into recovery and management plans for endangered fishes in the Colorado River Basin. Nearly all the endangered fishes investigations in the Upper Colorado River Basin have focused on the Upper Colorado River and Green River sub-basins. Documentation of Colorado squawfish and Gila sp. reproduction in the San Juan River in 1987 has added a third suG-basin in the Upper Colorado River Basin where recovery and ~ management of endangered fishes must be addressed. Endangered species studies of the San Juan River will have to be prioritized among on- - going and future studies in the Upper Colorado River Basin. The fol- lowing recommendations identify further investigations that should be conducted on the San. Juan River. There are topics addressed that - apply not only to the San Juan River, but the entire Upper Colorado ~ River Basin. At the time this report was completed, the cooperative agreement between BOR and the States of Utah and New Mexico was ex- tended for an additional year of investigation of the San Juan River. Thus, recommendations are also presented which specifically identify sampling techniques and sites for 1988. Identification of Colorado squawfish spawning areas in the San Juan River is necessary so that they can be protected and spawning monitored. Electrofishing during suspected times of spawning should be conducted in 1988 to attempt to locate spawning Colorado squaw- fish. Radio telemetry tracking of wild adult fish is another tech- nique that has proven successful in the Green River sub-basin for locating Colorado squawfish spawning areas. Electrofishing for spawning aggregations and radio telemetry tracking may have limited usefulness in the San Juan River because of the apparent low density of Colorado squawfish. Sampling with larval drift nets and seining backwaters for YOY fish would be useful techniques for identifying general river reaches where Colorado squawfish are spawning. Sampling ~ of backwaters in fall should be conducted in 1988 to further define the relative amount and sites of Colorado squawfish reproduction and the subsequent distribution of young fish. The high labor and time - costs of larval drift netting may limit its applicability. - 44 - ,