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<br />squawfish habitat preferences are similar to that of young-of-year fish, but they appear to <br />be mobile and more tolerant of lotic conditions away from the sheltered backwater <br />environment. <br /> <br />o <br />C,) <br />C" <br /> <br />~ <br />tv <br /> <br />As a result of the 1991 Biological Opinion issued by the Service for the proposed Animas- <br />la Plata Project, and a second such opinion issued in February 1996, Reclamation agreed <br />to fund approximately 7 years of research on the San Juan River and its tributaries, While <br />these studies are not yet complete, annual reports indicate that a small reproducing <br />population of Colorado squawfish exists in the San Juan River. Based on radio telemetry <br />studies and visual observations, two potential spawning areas have been located at river <br />mile 132.0 and 131,15 (Miller 1994, Ryden and Pfeifer 1995a). Both of these sites are <br />located in an area of the river known as the "Mixer" (RM 133.4 to RM 129.8). The <br />highest concentration of adult Colorado squawfish in the San Juan River occurs between <br />the Cudei Diversion (RM 142.01 and Four Corners (RM 119.2). Ryden and Pfeifer (1995al <br />report that a Colorado squawfish captured at river mile 74.8 (between Bluff and Mexican <br />Hat) made a 50-60 mile migration from near Bluff, Utah, to the Mixer during the suspected <br />spawning season in 1994. The fish then returned to within 0.4 river miles of its original <br />capture location, <br /> <br />i. ~ .~ <br /> <br />Successful reproduction was documented in the San Juan River in 1987, 1988, 1992, <br />1993, 1994, and 1995, by the collection of young-of-year Colorado squawfish. The <br />majority of the young-of-year squaw fish were collected in the San Juan River inflow to <br />lake Powell (Buntjer et al. 1994, lashmett 1994, Platania 1990, Platania, pers.comm. <br />1996), However, some young-of-year squawfish have also been collected from the <br />vicinity of the Mancos River confluence in New Mexico, in the vicinity of the Montezuma <br />Creek confluence near Bluff, Utah, and at a drift station near Mexican Hat, Utah (Buntjer et <br />al. 1994, Platania 1990, Platania, pers. comm. 1996). In 1994, a young-of-year Colorado <br />squawfish was collected at the confluence with the Mancos River, which is the first <br />specimen collected at this site since 1987 (5. Platania, University of New Mexico, pers. <br />comm.). <br /> <br />The San Juan River is one of only three remaining areas where a wild, reproducing <br />population of Colorado squawfish still persists. The San Juan River subbasin, isolated <br />from the Colorado and Green River _subbasins, provides a third population of wild fish, <br />contributing an additional essential buffer against a catastrophic event (such as an oil spill) <br />elsewhere in the basin. Because of this the Colorado River Fishes Recovery Team. <br />(consisting of scientists from the entire Colorado River Basin, including representatives <br />from State wildlife agencies of California. Arizona, New Mexico, Utah. and Colorado, as <br />- well as Federal representatives from the National Park Service, Tleclamation, and the <br />Service) recomr:nended that the San Juan River be added to the Colorado squawfish <br />recovery plan. The updated- Colorado Squawfish Recovery Plan (August 6, 1991) states <br />that the species can be downlisted to threatened when all recovery areas (including the <br />San Juan River from lake Powell upstream to the confluence of the Animas River) have <br />naturally self-sustaining populations. The San Juan River is also included in the delisting <br />criteria. <br /> <br />Critical Habitat <br /> <br />Critical habitat has been designated within the 100-year floodplain of the Colorado <br /> <br />7 <br />