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BIMP 2012 — Golden Opportunity and Santa Fe Project Site Report <br /> Submitted by Lance Carpenter <br /> January 13,2013 <br /> Project Overview—Bats/Inactive Mine Project <br /> The Colorado Parks & Wildlife (CPW) is responsible for the conservation of all bat species in Colorado. The <br /> Bureau of Land Management(BLM),United States Forest Service (USFS), and Division of Reclamation, <br /> Mining, and Safety (DRMS) are in partnership with the CPW to identify and protect those mines that provide <br /> significant roosts for populations of bats. These roosts may be critical to the long-term survival of populations <br /> of some bat species (Humphrey 1975). <br /> The Townsend's big-eared bat(Corynorhinus townsendii) is a Species of Special Concern in Colorado. It is <br /> primarily a cave-dwelling species but also roosts in man-made caves, analogues to abandoned mines. While <br /> most studies report a high degree of site fidelity by C. townsendii,there is evidence that some colonies use <br /> multiple roost sites. Sherwin et al. (2000) documented frequent movements among mines used by this species <br /> as maternity roosts. This bat is a colonial species and, unlike most species, avoids roosting in crevices. This <br /> habit makes them highly vulnerable to human disturbance. The species is a federal Species of Concern by the <br /> United States Fish and Wildlife Service (USFWS), a Species of Special Concern and Sensitive Species by the <br /> BLM and USFS in most areas, and a Special Status Species by most western states. The species is ranked as <br /> the highest priority by the Western Bat Working Group, and a recently completed Conservation Strategy for C. <br /> townsendii is available (Pierson et al. 1999). The loss of historical cave roosting habitat and the widespread <br /> closures of abandoned mines in the West are believed to have contributed to the species decline. This species is <br /> the focus of the Bats/Inactive Mine Project(BIMP). <br /> The primary objectives of the mine surveys for the Golden Opportunity and Santa Fe Project sites were to <br /> evaluate the bat roost potential of these mines that are scheduled for closure, identify important bat roosts, and <br /> make recommendations by installing bat gates where needed. These bat gates will provide protection and <br /> conservation of bat roosts and help prevent the decline of populations of some bat species. <br /> Internal and External Surveys <br /> After both external and internal surveys were completed, each mine site was scored on a scale of I to 3 to help <br /> further refine future survey efforts to investigate a site's potential use by bats during the summer, fall, and <br /> winter seasons. Priority 1 sites included mines that may provide suitable habitat for bats (i.e., complex mine <br /> structure, good airflow, favorable temperature, and relative humidity range) and/or showed direct evidence of <br /> use by bats, including the presence of guano or insect parts, or indication of a maternity roost. These sites were <br /> recommended to be gated. Priority 2 sites included mines that may or may not provide suitable habitat for bats, <br /> but further data(video surveys,trapping,winter surveys)was needed to help evaluate whether or not a mine <br /> should be gated. Priority 3 sites were not recommended to be gated and were removed from further survey <br /> efforts; these included mines with inadequate habitat for bats, portal entrances where vegetation impeded use by <br />