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37 The Animas, La Plata, Mancos, and San Juan Rivers in Colorado, New Mexico, and Utah currently support a large concentration of wintering bald eagles. Survey reports from the tri-State area indicate well over 100 birds overwintering in the area. While the number of birds in the area is somewhat variable, depending on the severity of the winter, their numbers have increased considerably in the last several years. Bald eagles also nest in the general area. There are two active nest sites associated with area reservoirs and a third historic site (currently inactive) along the Animas River. In 1989, Reclamation reported that approximately 70 bald eagles overwintered near the Navajo Reservoir, its associated tailwaters, and along the lower Animas River. The Colorado Division of Wildlife (Kevin Ellis, District Wildlife Manager, Durango, Colorado) estimates that the wintering population of bald eagles along the Animas River has nearly tripled in the past 5 years. Survey results show similar trends on the La Plata, Mancos, and San Juan Rivers in Colorado, New Mexico, and Utah. With such a large winter concentration of bald eagles within the Project area, it is probable that one or more communal roosts exist. Additional surveys and a concerted effort to locate and protect these "essential habitats' are integral to an eagle management plan. It is anticipated that the creation of the Ridges Basin Reservoir and associated fisheries in the area will attract wintering bald eagles, and it is conceivable that a new nest site could be established in the area. As with the endangered fish, the Service is concerned about potential water quality problems that may affect the bald eagles, both in the rivers and Ridges Basin Reservoir. Because the Ridges Basin Reservoir will be filled by water pumped out of the Animas River and it is situated in a location where selenium contamination could occur, a monitoring program should be developed to determine if heavy metals and/or selenium contamination become bioaccumulated in the food chain and become deleterious to bald eagles. If biomonitoring of food chain organisms within Project-affected rivers and the Ridges Basin Reservoir identifies contaminant levels of concern, then corrective measures would need to be implemented. It is the Service's biological opinion that the Project, as described herein, is not likely to jeopardize the continued existence of the bald eagle. Conservation Recommendations for the Bald EaGle The Service recommends that a Bald Eagle Management Plan be developed and implemented, concurrent with Project design and construction. Such a plan should be developed jointly by Reclamation, the Service, and the affected States. Specific surveys should be aimed at identifying possible communal roost sites and nest sites and methods to protect them. Potential contaminant bioaccumulation in the food chain should be assessed and monitored with corrective measures implemented as necessary. Results of ongoing Departmental contaminant studies on the San Juan River as well as results from biomonitoring of Project reservoirs and affected streams should be used to identify and correct any contamination problems that may arise as a result of Project construction and operation. .' , , ' -.; ! ~ ~; "~I ~., ~ ,. :'~