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• J.E. Stover & Associates, Inc January 19, 2007 Page 4 Impact Evaluations The following is an impact evaluation for two species determined to potentially occur within the mine boundary area (bald eagle and kit fox) and four endangered fish species whose downstream critical habitat is affected by water depletions in the San Miguel River drainage (bonytail, humpback chub, razorback sucker, and Colorado pikeminnow). Other species listed in Table 1 but not evaluated here were eliminated based on lack of suitable habitat within the mine permit boundary or because their known ranges are documented to lie well outside the mine boundary or its immediate vicinity. Bald eagle The bald eagle was listed as endangered in the conterminous U.S. by USFWS in 1967. Loss of habitat, shooting for feathers, and widespread use of the pesticide DDT are all thought to have contributed to the decline of this species; only 417 pairs were surveyed in the conterminous U.S. in 1963,12 down from several hundred thousand before the arrival of Europeans on this continent. Since domestic use of DDT was banned in 1972, bald eagle populations have increased dramatically, nearly doubling every 8 years. Approximately 6,500 pairs of bald eagles were recorded in the conterminous U.S. in 2000. In 2001, 45 resident pairs were recorded in Colorado, up from 11 pairs in 1990.12 The bald eagle was down-listed to threatened in 1995 at Federal Register 60(133):35999-36010, and proposed for de-listing in 1999 at Federal Register 64(128):36453-36464. On February 16, 2006, USFWS reopened the public comment period on delisting the bald eagle in the lower 48 states at Federal Register 71(32):8238-8251 and indicated that the bald eagle is considered recovered. No critical habitat has been designated for bald eagles. Bald eagles prefer coastal areas, rivers, or lakeshores with tall diurnal perches. In Colorado, bald eagles are rare summer breeders and common winter residents primarily in mountain parks and western river valleys.13 During the night, wintering bald eagles roost in tall trees, or occasionally, cliffs,14 up to 20 miles from foraging areas.15 Bald eagles may select night roosts that offer protection from winter winds and where thermoclines provide warmer temperatures than foraging areas.75'14 In daytime, eagles make foraging flights from night roosts, alighting on the ground to capture prey or feed on carrion and frequently resting in tall trees or, less commonly, on manmade structures. Fidelity to night roosts is low.15 The entire mine permit area lies within bald eagle winter range mapped by CDOW.6 CDOW- mapped bald eagle winter concentration areas exist within 4 miles east of the mine permit boundary in the San Miguel River and Naturita Creek corridors.6 Bald eagles may forage for rodents and carrion across the open shrublands of the mine permit area. However, given the preferred habitat available to bald eagles on Naturita Creek (in Naturita Canyon) and on the San Miguel River, which provide their preferred prey (fish and waterfowl), it is likely that bald eagles occur only infrequently within the mine permit boundary. The lands within the Hamilton Mine boundary contribute only marginally to sustaining wintering bald eagle populations in the vicinity. Given the habitat characteristics and the lack of human activity within the mine permit boundary, renewal of the Hamilton Mine permit is not likely to cause measurable effects on bald eagles. "USFWS. 2006. Population data for the bald eagle. Available at http://midwest.fws.gov/eagle/. Accessetl March 3. '3 Andrews, R. and R. Righter. 1992. Colorado Birds. Denver: Denver Museum of Natural History. 442 pp. '4 Buehler, D. A. 2000. Bald Eagle (Haliaeetus leucocephalus). In The Birds of North America, No. 506 (A. Poole antl F. Gill, eds.). The Academy of Natural Sciences, Philatlelphia, antl the American Ornithologists' Union, Washington, D.C. 's Moynahan, Brendan (BLM Grand Junction Fieltl Office Wildlife Biologist). 2006. Personal communication with Dawn Reeder (Rare Earth Science, LLC), March 8. ® Rdre Firth Science, LLC