PERMFILE123364 - Laserfiche WebLink

Home Browse Search

Lorenrito Canvon Mine - wldli(e Technical ReOOrt • Threatened and Endangered Species The U.S. Fish and Wildlife Service has identified eleven threatened, endangered, and species of special concern wildlife that occur or potentially occur within the permit area. These species include the black-footed ferret, bald eagle, peregrine falcon, Mexican spotted owl, swift fox, Texas horned lizard, mountain plover, southwestern willow flycatcher, Baird's sparrow, ferruginous hawk, and burrowing owl. The following describes the habitat requirements of each species and their potential for occurrence within the permit area. Black-Footed Ferret The black-footed ferret is afederally-listed endangered species. Black-footed ferrets aze primarily nocturnal animals that are nearly always associated with prairie dogs. Ferrets may occur within the colonies of either white-tailed or black-tailed prairie dogs. The permit area is within the occupied range of the black-tailed prairie dog. Prairie dogs are the ferret's source of prey and the prairie dogs' burrows provide dens and rearing areas for the ferret's young. A single black-tailed prairie dog colony of 80 ha (200 acres) or a complex of smaller colonies occurring within a circle with a 7-km (4.3-mi) radius that totals 80 ha is considered to be the minimal size necessary to constitute potential habitat for the black-footed ferret (USFWS, 1989). • The permit azea is within the historical range of the black-footed ferret. However, the occurrence of ferrets within the permit area is not expected. This conclusion is based on the following consideration. During the 1996 field surveys no prairie dog colonies were observed within the permit area. Therefore, ferrets are not anticipated to occur within the permit area. Bald Eagle Feeding areas, diurnal perches, and night roosts are fundamental elements of bald eagle winter range. Although eagles can fly as faz as 24 km (15 mi) to and from these elements, they primarily occur where all three elements are available in comparatively close proximity (Swisher, 1964). Although eagle presence in winter is not necessazily related to open water (Swisher, 1964), eagles usually occur near lazge rivers and lakes (Sprunt and Ligas, 1963). Because the eagle's use of water areas generally decreases as ice cover increases (Fitzgerald and LaBond, 1980), open water is considered an important feature of their winter habitat (Snow, 1973). Eagles are particularly attracted to lazge bodies of water downstream from hydroelectric dams where dead or dying fish or waterfowl are readily accessible (Cooksey, 1962; Ingram, 1965). Food availability is probably the single most important factor affecting winter eagle distribution and abundance (Steenhof, 1978). Fish and waterfowl are the primary food sources where eagles occur along rivers, lakes, streams, and dams. Waterfowl, such as dead, sick, or crippled • individuals are often taken when fish are not readily available (Shickley, 1961; Spencer, 1976). Wildlife.476/Dceember U. 1996 22