Ovis canadensis sierrae NatureServe Explorer Species Reports — NatureServe Explorer is a source for authoritative conservation information on more than 50,000 plants, animals and ecological communtities of the U.S and Canada. NatureServe Explorer provides in-depth information on rare and endangered species, but includes common plants and animals too. NatureServe Explorer is a product of NatureServe in collaboration with the Natural Heritage Network.
ITIS Reports — Ovis canadensis sierrae ITIS (the Integrated Taxonomic Information System) is a source for authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world. Sierra bighorn range in color from white to dark brown, with a white rump and dark tail. There is some seasonal change in coloration due to the shedding of a thicker winter layer. Specialized hooves with adhesive soles provide traction in steep rocky terrain. Female bighorn (ewes) can weigh up to 70 kilograms (155 lb) and have shorter, narrow horns, while male bighorn (rams) can weigh as much as 100 kilograms (220 lb) and have massive, curving horns. The horns of both rams and ewes are composed of a dense layer of keratin covering a core of bone.
FWS Digital Media Library — The U.S. Fish and Wildlife Service’s National Digital Library is a searchable collection of selected images, historical artifacts, audio clips, publications, and video. The Sierra Nevada bighorn sheep (Ovis canadensis sierrae) is subspecies of bighorn sheep unique to the Sierra Nevada mountains of California. A 2016 genetics study confirmed significant divergence between the three subspecies of North America’s bighorn sheep: Sierra Nevada bighorn sheep, Rocky Mountain bighorn sheep and desert bighorn sheep. Sierra Nevada bighorn sheep were listed as a federally endangered subspecies in 2000. As of 2016, over 600 Sierra bighorn remain in the wild.