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depend on birds and mammals for dispersal. C and J Gravel contributes ten cents for each ton they sell to a mitigation fund for the purpose of managing resources in the Grandview Ridge. Big game species, including mule deer (Odocoileus hemionus) and elk (Cervus elaphus) are also common in pinon juniper woodlands. While juniper is only marginally palatable to mule deer and elk, other shrubs such as mountain mahogany, generally found in association with pinon- juniper, are an important browse plant for mule deer. Pinon juniper woodlands also provide important winter cover for deer and elk. These pinon juniper/mixed shrub habitats are used by big game from October through late April, depending on annual snowfall, as important winter range. The BLM portion of the project area is located within the Grandview Ridge Management Area (GRMA). According to the Grandview Ridge Management Plan, mule deer and elk are identified as having special significance within the GRMA. The Grandview Ridge Management Plan authorizes a seasonal closure to the public during winter to ensure undisturbed deer and elk winter range. This closure is conditions-based, lasting no more than the time period of December 1 through April 15, and in mild winters may be implemented for only brief periods of time, or not at all. BLM has prohibited any clearing of vegetation by gravel operations during this period. Grandview Ridge, including BLM and adjacent non-federal properties, provides important historic big game winter range and travel corridors for animals moving between traditional winter grounds south of Highway 160 and summering areas to the north such as on Missionary Ridge. The Grandview Ridge conditions-based seasonal closure is designed to protect and maintain habitat capability for big game wintering and traveling through BLM's Grandview property. La Plata County and the Colorado Division of Wildlife (CDOW) have also mapped critical winter habitat for mule deer and elk within the GRMA. Winter habitat is largely restricted to elevations ranging from 6,500 to 9,000 feet. Narrow drainages adjacent to the project area, such as Sale Barn Canyon, offer particularly sheltered winter habitat for big game species. Bird species with potential to breed in the project area vicinity may include mourning dove (Zenaida macroura), common nighthawk (Chordeiles minor), black-chinned hummingbird (Archilochus oberholseri), black-billed magpie (Pica hudsonica), blue-gray gnatcatcher (Polioptila caerulea), bluebirds (Sialia spp.), and green-tailed towhee (Pipilo chlorurus), to name a few. Based on the age and structure of the pinon juniper woodland in the proposed project area, the following raptor species could potentially utilize the project area: Cooper's hawk (Accipiter cooperii) and sharp-shinned hawk (Accipiter striatus). The overall woodland is too young (i.e., the trees are too small) to serve as nest substrates for species such as red-tailed hawk (Buteo jamaicensis), northern goshawk (Accipiter gentiles), or great-horned owl (Bubo virginianus). The past thinning treatments have opened the stand, providing potential foraging habitat for larger raptors such as golden eagles and red-tailed hawks. There are two known golden eagle nests within 7.0 miles of the project area (Bureau of Reclamation, unpublished data). Golden eagle territories in the west typically range from 12-20 square miles (Kochert et al. 2002); therefore, the proximity of these nests indicates that golden eagles may potentially utilize the project area for foraging. However, because of the continued intensive noise and human activity associated with the adjacent active mining pit, the analysis area is considered only marginally suitable for raptor foraging. Grandview Gravel Pit Expansion Environmental Assessment 43