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!'- . . 4 The Ridges Basin and Southern Ute Reservoirs may support some bald eagle needs during the summer. It is doubtful that Ridges Basin Reservoir will be available to wintering bald eagles because of ice cover. Conversely, the Southern Ute Reservoir has potential to support these wintering birds. To afford the bald eagle full consideration in the design and management of the project we suggest a Bald Eagle Reservoir Management Plan be developed for the reservoirs. The Colorado squawfish. listed as endangered in 1967. was once wide- spread and abundant throughout the mainstream Colorado River and its major tributaries. including the San Juan and Animas Rivers. Dams, diversion of water and reclamation of pre-impoundment rivers are all factors that have reduced the range of the largest minnow in the United States by about 75%. Additional factors believed to limit squawfish include competition with exotic fish species and pollution in the form of pesticides and chemicals. The San Juan River is one of only a few Colorado River streams where any squawfish have been found in recent surveys. Prior to the construction of Navajo Dam (1962). squawfish were regularly reported from the San Juan River in New Mexico and. to a lesser extent. in Colorado and Utah. In preparation for development of a quality trout fisheries in the Reservoir and below the Dam, large reaches of the San Juan River and its tributaries were reclaimed. The reclamation and habitat changes associated with the Dam apparently eliminated squawfish from the upper river, as several fish surveys in the late 1970's failed to locate the species. Both the Animas and La Plata Rivers now regularly go dry along once permanent reaches because of diversion. and no longer are believed to be suitable squawfish habitat. In April 1978, a survey crew sponsored by the Bureau of Reclamation did locate a juvenile squawfish in the San Juan River at the mouth of McElmo Creek. near Aneth, Utah. The size (170 mm) and locality of the specimens indicated it was spawned in the San Juan River, probably in 1975 or 1976. making the San Juan River one of only three known rivers where successful reproduction has occurred in the last five years. As proposed. the project will reduce the average annual inflow of water into the San Juan River by 198,200 acre feet, or 13% of the 1939-77 average annual flow. In addition, the project will increase the salinity of the remaining San Juan River water from 470 to 520 mg/l. Both of these .