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on~~58 ., In 1996 the Service concluded that the change to a pool management concept for releases downstream from McPhee Reservoir may affect, but not likely adversely affect, endangered fish in the Colorado River because it would result in increased flows in the Dolores River and management flexibility which allows higher spring flows (Fish and Wildlife Service, 1996). The pool management concept included acquiring water intended for use in the San Juan drainage and releasing it down the Dolores River. To date, 3,900 acre-feet of such water has been acquired. In the 1996 letter, the Service discussed effects on the San Juan River and concluded "Less water may be returned to the San Juan River because of increased releases to the Dolores River; however, there will still be additional water released to the San Juan River from the Dolores Project which would otherwise not be added to the San Juan River." Consequently the Service concurred that the Colorado pikeminnow and razorback sucker would not be affected in the San Juan River. Species that could occur in the general area include the Mancos milk-vetch, Knowlton's cactus, Mesa Verde cactus, bald eagle, southwestern willow flycatcher, Mexican spotted owl, and black- footed ferret. Bald eagles overwinter in the area and regularly use the Dolores River downstream from McPhee. The Mexican spotted owl is known to nest in Mesa Verde National Park, while southwestern willow flycatchers have been recorded in various drainages in the Dolores project area during migration seasons. The Service has concurred that there will be no effect to the Mancos milk-vetch, Knowlton's cactus, Mesa Verde cactus, Mexican spotted owl, and the black footed ferret. Potential habitat for these species would not be affected by the conversion of dry farmland to irrigated land or by the use of the 8,000 acre-feet of water. The Service also concurred that the bald eagle and southwestern willow flycatcher may be affected but would not likely to be adversely affected. These species may be affected by accumulating selenium from food items; and as indicated previously, selenium can be mobilized from the new irrigation lands and salinity levels can be increased through water depletion. The magnitude of salt or selenium loading from the new lands is predicted to be low and thus species are not likely to be adversely affected. The Colorado pikeminnow and razorback sucker occur in the San Juan River which receives return flows from much of the irrigated land in the area, and these species and the endangered humpback chub and bonytail occur in the Colorado River which is fed by the Dolores River. The Colorado pikeminnow has also been recorded in the Dolores River near the confluence with the Colorado River (Valdez, et ai, 1992) and plans of the Upper Colorado Rive Recovery Program (Recovery Program) are to stock the pikeminnow in the Dolores in the future. Both the Colorado and San Juan rivers downstream from the undertaking are designated as critical habitat for the endangered fish. Any depletion of flows could affect these species. The Service concurred that selenium and salt loading in the San Juan River Basin as a result of the new irrigation may affect, but not be likely to adversely affect, the Colorado pikeminnow and razorback sucker and their critical habitat due to insignificant impacts relative to the expected 13