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::> :) .) 7 " small reproducing population of Colorado squawfish exists in the San Juan River. Based on radio telemetry studies and visual observations, two potential spawning areas have been located at river mile 132.0 and 131.15 (Miller 1994, Ryden and Pfeifer 1995a). Both of these sites are located in an area of the river known as the "Mixer" (RM 133.4 to RM 129.8). The highest concentration of adult Colorado squawfish in the San Juan River occurs between the Cudei Diversion (RM 142.0) and Four Corners (RM 119.21. Ryden and Pfeifer (1995a) report that a Colorado squawfish captured at river mile 74.8 (between Bluff and Mexican Hat) made a 50-60 mile migration from near Bluff, Utah, to the Mixer during the suspected spawning season in 1994. The fish then returned to within 0.4 river miles of its original capture location. :::l o Successful reproduction was documented in the San Juan River in 1987, 1988, 1992, 1993, 1994, and 1995, by the collection of young-of-year Colorado squawfish. The majority of the young-of-year squaw fish were collected in the San Juan River inflow to Lake Powell (Buntjer et al. 1994, Lashmett 1994, Platania 1990, Platania, pers.comm. 1996). However, some young-of-year squawfish have also been collected from the vicinity of the Mancos River confluence in New Mexico, in the vicinity of the Mo"ntezuma Creek confluence near Bluff, Utah, and at a drift station near Mexican Hat, Utah (Buntjer et at. 1994, Platania 1990, Platania, pers. comm. 1996). In 1994, a young-of-year Colorado squawfish was collected at the confluence with the Mancos River, which is the first specimen collected at this site since 1987 (S. Platania, University of New Mexico, pers. comm.). The San Juan River is one of only three remaining areas where a wild, reproducinl;l population of Colorado squawfish stili persists. The San Juan River subbasin, Isolated from the Colorado and Green River subbasins, provides a third population of wild fish, contributing an additional essential buffer against a catastrophic event (such as an oil spill) elsewhere in the basin. While the Colorado squaw fish population may be small in the San Juan River, it may be important as unique genetic stock. Because of this the Colorado River Fishes Recovery Team (consisting of scientists from the entire Colorado River Basin, including representatives from State wildlife agencies of California, Arizona, New Mexico, Utah, and Colorado, as well as Federal representatives from the National Park Service, Reclamation, and the Service) recommended that the San Juan River be added to the Colorado squawfish recovery plan. The updated Colorado Squawfish Recovery Plan (August 6, 1991) states that the species can be downlisted to threatened when all repovery areas (including the San Juan River from Lake Powell upstream to the confluence of the Animas River) have naturally self-sustaining populations. The San Juan River is also included in the delisting criteria. Critical Habitat Critical habitat has been designated within the 1 DO-year floodplain of the Colorado SQuawfish's historical range in the following section of the San Juan River Basin (59 FR 13374). New Mexico. San Juan County; and Utah. San Juan County. The San Juan River from the State Route 371 Bridge in T. 29 N., R. 13 W., section 17 to Neskahai Canyon up to the full pool elevation in the San Juan arm of Lake Powell in T. 41 S., R. 11 E., section 26.