FWS designates critical habitat for Sierra Nevada bighorn sheep
73 Fed. Reg. 45534 (Tuesday, August 5, 2008)(DEPARTMENT OF THE INTERIOR; Fish and Wildlife Service; 50 CFR Part 17; Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra Nevada Bighorn Sheep (Ovis canadensis sierrae) and Taxonomic Revision; Final rule).
Sierra Nevada bighorn sheep inhabit open areas where the land is rocky, sparsely vegetated, and characterized by steep slopes and canyons. Mitochondrial DNAanalysis of bighorn sheep shows that mammals from the Sierra Nevada could be distinguished from populations of other subspecies of bighorn sheep, even among populations that are adjacent to one another and separated by short distances. Photo from UC Davis Vetinary Genetics Laboratory.
SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are designating critical habitat for the Sierra Nevada bighorn sheep (Ovis canadensis sierrae) under the Endangered Species Act of 1973, as amended (Act). In total, approximately 417,577 acres (ac) (168,992 hectares (ha)) fall within the boundaries of the critical habitat designation. The critical habitat is located in Tuolumne, Mono, Fresno, Inyo, and Tulare Counties, California. We also are finalizing the revision of taxonomy of the listed entity from a distinct population segment (DPS) of California bighorn sheep (Ovis canadensis californiana) to subspecies, Ovis canadensis sierrae, based on recent published information. DATES: This rule becomes effective on September 4, 2008.
EXCERPT RE: LOCATIONS: We are designating 12 units as critical habitat for the Sierra Nevada bighorn sheep... Mount Warren, Mount Gibbs, Convict Creek, Wheeler Ridge, Taboose Creek, Sawmill Canyon, Mount Baxter, Mount Williamson, Big Arroyo, Mount Langley, Laurel Creek, and Olancha Peak.
EXCERPT RE: PRIMARY CONSTITUENT ELEMENTS: We consider the physical or biological features to be the PCEs (or "primary constituent elements") laid out in the appropriate quantity and spatial arrangement for the conservation of the species. The PCEs include, but are not limited to: (1) Space for individual and population growth and for normal behavior; (2) Food, water, air, light, minerals, or other nutritional or physiological requirements; (3) Cover or shelter; (4) Sites for breeding, reproduction, and rearing (or development) of offspring; and (5) Habitats that are protected from disturbance or are representative of the historic, geographical, and ecological distributions of a species... Based on the above needs and our
current knowledge of the life history, biology, and ecology of the subspecies, we have determined that the Sierra Nevada bighorn sheep’s PCEs are: (1) Non-forested habitats or forest openings within the Sierra Nevada from 4,000 ft (1,219 m) to 14,500 ft (4,420 m) in elevation with steep (greater than or equal to 60 percent slope), rocky slopes that provide for foraging, mating, lambing, predator avoidance, and bedding and that allow for seasonal elevational movements between these areas. (2) Presence of a variety of forage plants as indicated by the presence of grasses (e.g., Achnanthera spp.; Elymus spp.) and browse (e.g., Ribes spp.; Artemisia spp., Purshia spp.) in winter, and grasses, browse, sedges (e.g., Carex spp.) and forbs (e.g., Eriogonum spp.) in summer. (3) Presence of granite outcroppings containing minerals such as sodium, calcium, iron, and phosphorus that could be used as mineral licks in order to meet nutritional needs.
OTHER RESOURCES: For more information on the Sierra Nevada bighorn sheep, refer to the final listing rule published in the Federal Register on January 3, 2000 (65 FR 20) and the proposed critical habitat rule published in the Federal Register on July 25, 2007 (72 FR 40955), or see ESA blawg (Feb. 12, 2008).