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o <::) (-) '. -. 14 I-A CJi The bald eagle was listed on February 14, 1978, as endangered in the conterminous United States, except for Washington, Oregon, Minnesota, Wisconsin, and Michigan, where its status is threatened. The reasons for its decline and subsequent listing included chemical contamination, chiefly by organochlorine pesticides, causing severe population declines and local extirpation throughout the species' range, through reproductive failure and direct toxicity; other contributing factors included degradation and loss of habitat, killing, and human disturbance. Based upon response to recovery efforts, the species' classification was upgraded to threatened throughout the conterminous United States on August 11, 1995. Bald eagles enter New Mexico in October and November and leave in March or early April. While in the state, most tend to congregate around reservoirs and other sizeable bodies of water, including larger rivers such as the San Juan. The predominantly piscivorous bald eagle utilizes fish and waterfowl for up to 90 percent of its diet. Since wintering bald eagle surveys were initiated by the New Mexico Department of Game and Fish in 1982, a gradual upward trend in abundance has been observed. Mirroring the state-wide trend. abundance of bald eagles wintering along the San Juan River and around Navajo Reservoir have also increased. Recent findings of contaminants in the San Juan River and in areas adjacent to the river have focused attention on the concerns of heavy metal, hydrocarbon, and selenium contamination and subsequent impacts upon the predatory and scavenging bald eagle. The peregrine falcon was listed as endangered in 1970 because of pesticide-induced reproductive failure. Peregrine falcons feed almost exclusively on birds; pigeons, medium-sized passerines, shorebirds, and medium to small waterfowl. Although no peregrine aeries are currently known within the San Juan River Valley affected by the proposed action, the species may utilize the area during migration and prey upon avian species feeding along the river or its adjacent floodplain. The Colorado squawfish was listed as endangered on March 11, 1967. Habitat alteration, fragmentation, and degradation arising from dam construction; and competition and predation from introduced non-native fishes have been cited as the major factors responsible for the decline of the species. As a top level predator, the Colorado squawfish may experience bioaccumulation of contaminants from its prey. Endemic to the Colorado River basin, the squawfish has historically been found in the San Juan River and anecdotal reports of the species in the Animas River have also been recorded. Recent collections have yielded a total of 20 young-of-the-year squawfish in backwaters of the San Juan River or larval drift collections at various locations downstream of Shiprock, New Mexico. In the summer of 1996 two juvenile Colorado squawfish (350-450 mm TL) were captured in the lower 12 miles of the San Juan River. Since 1991, 17 adult squawfish have been captured downstream of Shiprock and several others observed in the river between the Hogback and Aneth, Utah. The rediscovery of adult Colorado squawfish, presence of several age classes, and documentation of its successful spawning in the San Juan River reconfirmed the species as a viable component of the ichthyofauna of the San Juan River. Critical habitat has been designated for the Colorado squawfish in the San Juan River and its 100-year floodplain from New Mexico State Route 371 Bridge in T.29N., R.13W., section 17 (New Mexico Meridian) to Neskahai Canyon in the San Juan arm of Lake Powell in T.41S.,