2008-02-04_PERMIT FILE - C1982056A

Home Browse Search

Sagebrush, sagebrush/meadow, reclaimed pastureland, and cropland are the only habitats that will be disturbed by development of the proposed mine facilities. A maximum of only 7.5 acres of sagebrush and 0.5 acres of sagebrush/meadow will be disturbed. The remaining disturbance will be within reclaimed pastureland and cropland. The vegetation communities existing within and adjacent to [he proposed permit boundaries are indicative of the wildlife species utilizing the area. A discussion of the plant communities and corresponding habitat types occurring within the Twentymile Park permit area is provided below. Sagebrush Physiographically, sagebrush occurs primarily on non-cultivated land between meadow (lower elevations) and mountain shrub (higher elevations) vegetation types. Sagebrush communities are either dominated by big sagebrush or low sagebrush. Big bluegrass (Poo ampla), slender whea[grass (AgronYron trachycaulum), mulesears +vyethia (Wyethia amplexicaulis), western yarrow (Achilles millifolium), and lupine (Lupinus spp.) are predominant understory species. Sagebrush habitat covers approximately 2,253 acres of [he permit area and accounts far 17 percent of the total surface acreage within the permit area. Mule deer rely on sagebrush habitat throughout [he year, but heaviest use occurs during the winter months when sagebrush (in areas not covered by snow) is an important winter browse species for mule deer. Sagebrush habitat on south-facia, slopes, wind-swept ridges, and other areas exhibiting reduced snow cover are especially important to nwle deer during [he winter months. The presence of mule deer winter range in the permit area is discussed in greater detail in a subsequent section. Many predators such as coyote, badger, long-[ailed weasel, golden eagle, red-tailed hawk, prairie falcon, and prairie rattlesnake utilize sagebrush habitat. • Several species of songbirds are considered obligates of (i.e., almost entirely dependent on) sagebrush habitat. Obligate species include sage thrasher and Bre+aer's sparrow. Vesper sparrow-, mourning dove, and western meado+vlark are also common in sagebrush habitat. Sage grouse are likely to occur throughout the sagebrush habitat and are almost totally dependent on sagebrush habitat (Braun et al. 1977). While open areas in low sagebrush tnay be used for strutting grounds, nests are constructed on the ground beneath sagebrush and most sage grouse foraging occurs in sagebrush habitat. Two sage grouse strutting grounds are located on or near the permit area. These grounds and the importance of permit area sagebrush habitat to sage grouse are discussed in greater detail in a subsequent section. Sagebrush/meadow and Meadow Sagebrush/meadow habitat is associated primarily with the bottomland along Fish Creek. It occurs on 471 acres and accounts for only 3.6 percent of the permit area. Silver sagebrush (Artemisia cans) is the dominant overstory species, while grasses, sedges, and rush dominate the understory. Kentucky bluegrass (Poo oratensis), Baltic rush (Juncos balticus), and cliff sedge (Carer scooulorum) are common understory species. Meadow habitat is very limited in areal extent (occupying 361 acres) and occurs as isolated narrow bands along intermittent drainages in dte permit area. It accounts for only 2.8 percent of [he permit area. Vegetation species present in this habitat are similar to those occurring in sagebrush/meadow except the shrub component (primarily silver sagebrush) is absent. In many areas meadow and sagebrush meadow have been heavily grazed by livestock. Thistle (Cirsium spp.) is a common invader species in these areas. • Sagebrush/meado+v is inhabited principally by wildlife species which prefer open grassland, although wildlife species diversity in these habitats is limited because of the isolated nature of these habitats. Other species, such as mule deer, may use meadow habitat along the drainages as corridors linking areas of suitable shrub habitat. MR 97-li-I 2.OJ-6~ Revised 10/02/97