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riverine habitat. Twelve razorback sucker, however, were collected in _ the San Juan Arm of Lake Powell by BOR during netting operations, -- March 18 - April 12, 1987. All of these fish were caught at RMI 0.0, on the south shore of the lake very near where the concrete boat ramp ~ at Piute Farms Marina now exists. Well over half (eight) of the razorback sucker collected were in a sexually ripe condition (Appendix A). The eight fish were male, and milt was easily extracted when the fish were stroked by hand. During this spring sampling period, six of the razorback sucker were subsequently recaptured at the origina l site, even after some of them were released up to one mile away from ~ the capture site. The apparent concentration of these fish in one area would indicate that they were either attempting to spawn in the lake, or were staging prior to migration to a spawning site. Fish collections from the San Juan River, Utah within the last several decades indicate limited size and distribution of rare fish '~ populations. Sigler and Miller (1963) collected three Colorado squaw- fish in 1960 at Mexican Hat, Utah. During 1976 razorback sucker were found in an irrigation pond near Bluff, Utah (BLM 1981). Sublette {1977) reported no endangered species from his sampling efforts, which were primarily made with seines. In 1978 VTN (1978) captured one Colorado squawfish while electrofishing near Aneth, Utah. The U.S. ~ Bureau of Land Management (BLM 1981) also captured a single Colorado squawfish in 1978 near Mexican Hat, Utah. Results of sampling the San - Juan River, Utah in 1987 have continued to indicate limited size and distribution of rare fish populations. The scarcity of records of razorback sucker in the San Juan River ~ may be an indication of their limited abundance and localized distri- bution. The razorback sucker was not collected during this study or by Sublette (1977). Sublette commented that there were "no definitive records....from the San Juan Basin;" hearsay records at Durango, Colorado were cited from Jordan (1890). Records of the BLM show, however, razorback sucker were seined from an irrigation pond near . Bluff, Utah in 1976 (BLM 1981). Razorbacks were also seined from backwaters of the San Juan River downstream of the irrigation pond (Mr. Neil Armantrout, U.S. Bureau of Land Management, Eugene, Oregon, pers. comm.). Historical information on the occurrence and distribution of Gila ~ spp, in the San Juan River Basin is relatively scarce. VTN's (1978 literature review revealed no verified specimens of humpback or bony- tail chub exist from the San Juan River. Additionally, VTN inter- viewed Dr. R. R. Miller (Museum of Zoology, University of Michigan, Ann Arbor, Michigan), whose review of the Gila complex indicated that . bonytail chub never occurred in the San Juan River. Sublette (1977) collected four roundtail chub specimens from the Los Pinos River above _ Navajo Dam; he found it widespread, but rare throughout the basin above Navajo Dam. It seems likely, therefore, that the Gila sp. collected in this study were roundtail chub and may have drifted - downstream from New Mexico. ~ - 12 - ,