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. . Colorado Congressional Delegation/Maynes Page 3 May 4, 1990 Mexico and Utah and the Service also confirm these conclusions. In those investigations, a total of only seven adult Colorado squawfish were captured in the San Juan River in the area from Shiprock, New Mexico to the inflow area of Lake Powell. One of these was captured in the inflow area of Lake Powell in April of 1987 and recaptured five months later near Bluff, about 145 kilometers upstream from its original capture location. In addition to adult fish captured in this reach, a total of only 18 young-of-the-year were captu red. Most of these collections were made in Utah in 1987 in the reach just above the inflow area of Lake Powell. No endangered fish were re- covered in biological investigations of the San Juan River in 1989. No Colorado squawfish in age classes between young-of-the-year and adult were found. Fifteen adult razorback sucker, a species currently under review for federal endangered species listing, were found at Piute Farms, the inflow area to Lake Powell, although one razorback sucker was captured in the San Juan River near Bluff, Utah. Despite the 1987 finding of reproduction of squawfish in the San Juan, the extent of annual recruitment and of the survivability of young fish has not yet been determined. In all likelihood, recruitment of these age classes, other than young of the year, is limiting the population of the squawfish in the San Juan. The explanation to account for limited recruitment, however, is unclear. Many explanations have been formulated to account for limited recruitment in other areas occupied by the species, predation by non-native species such as channel catfish, red shiner, fathead minnow and common carp; changes in water quality, including temperature, conductivity and pesticides; and changes in available habitat because of regulation of the river. As part of the San Juan. River investigations initiated in 1987, a Fishery Management Plan will be prepared by the cooperating natural resource agencies in Utah and New Mexico and the Bureau of Reclamation. The Fishery Management Plan will summarize the 1987-1989 biological information and review the hydrology of the San Juan River Basin as affected by existing projects. The Plan will assess the conditions of the river as related to non-native proliferation, overall fish habitat availability, and presence or absence of federally listed species. Further, the Plan will recommend needed studies and identify action which might be beneficial to the recovery of the species. The Fishery Management Plan is tentatively scheduled for completion in 1990. The Bureau has offered to work with the states of New Mexico and Utah as well as the Fish and Wildlife Service in developing a program to implement recovery actions identified in the Plan. The best available scientific evidence fails to substantiate the need for the type of Basin-wide mitigation for the Animas-La Plata Project requested by the Service.