Sierra Nevada bighorn sheep (Ovis canadensis ssp. sierrae)
The Sierra Nevada bighorn sheep is similar in appearance to other desert associated bighorn sheep. The species' coat shows a great deal of color variation, ranging from almost white to fairly dark brown. The belly, rump patch, back of legs, muzzle, and eye patch are all white. Males and females have permanent horns, but they are much larger in males. In females, the horns are slender and sabre-like, never forming more than half a curl. In males, the horns are massive and curl up, back over the ears, then curve down, forward, and up past the cheeks. As the animals age, their horns become rough and scarred, and will vary in color from yellowish-brown to dark brown. In comparison to many other desert bighorn sheep, the horns of the Sierra Nevada bighorn sheep are generally more divergent as they coil out from the base. Adult male sheep stand up to 1 meter (3 feet) tall at the shoulder; males weigh up to 99 kilograms (220 pounds) and females 63 kilograms (140 pounds).
- States/US Territories in which the Sierra Nevada bighorn sheep, Sierra Nevada is known to or is believed to occur: California
- US Counties in which the Sierra Nevada bighorn sheep, Sierra Nevada is known to or is believed to occur: View All
|Status||Date Listed||Lead Region||Where Listed|
|1999-04-20||California/Nevada Region (Region 8)||U.S.A. (CA) Sierra Nevada|
» Federal Register Documents
|Date||Title||Plan Action Status||Plan Status|
|2007-09-24||Final Recovery Plan for the Sierra Nevada Bighorn Sheep (Ovis canadensis californiana)||View Implementation Progress||Final|
|Date||Citation Page||Title||Document Type|
|2008-02-13||73 FR 8345 8346||Recovery Plan for the Sierra Nevada Bighorn Sheep (Ovis canadensis californiana)||
|2009-03-25||74 FR 12878 12883||Initiation of 5-Year Reviews of 58 Species in California, Nevada, Arizona, and Utah; Availability of Completed 5-Year Reviews in California and Nevada||
|2007-02-14||72 FR 7064 7084||Initiation of 5-Year Reviews of 58 Species in California and Nevada; Availability of Completed 5-Year Reviews in California and Nevada||
|2003-07-30||68 FR 44808 44808||Draft Recovery Plan for the Sierra Nevada Bighorn Sheep||
|2012-04-27||77 FR 25112 25116||5-Year Reviews of Species in California and Nevada||
|2008-09-30||Sierra Nevada Bighorn Sheep 5-Year Review|
» Critical Habitat
|Date||Citation Page||Title||Document Type||Status|
|2008-08-05||73 FR 45534 45604||Designation of Critical Habitat for the Sierra Nevada Bighorn Sheep (Ovis canadensis sierrae) and Taxonomic Revision; Final Rule||Final Rule||Final designated|
|2007-07-25||72 FR 40956 41008||Designation of Critical Habitat for the Sierra Nevada Bighorn Sheep (Ovis canadensis californiana) and Proposed Taxonomic Revision||Proposed Rule||Not Required|
To learn more about critical habitat please see http://ecos.fws.gov/crithab
» Conservation Plans
No conservation plans have been created for Sierra Nevada bighorn sheep.
» Life History
Male and female bighorn sheep commonly live in separate groups during much of the year, and often occupy different habitats. Males join females during the breeding (rutting) season in late fall. Bighorn sheep have a polygynous mating system with males compete for breeding dominance during the rutting period, which extends from late September through December. The peak of mating occurs in early November with a 180 day gestation period following conception. Bighorn sheep generally give birth to single young, but there is a low incidence of twins. Most lambs are born during May but may be born between mid-April and early July. As new forages grow in the spring with warming temperatures, bighorn sheep begin migrating to higher elevations and ewes give birth to lambs in extremely steep terrain. Within a matter of days, newborn lambs begin following their mothers and continue migrating to higher elevations.
» Other Resources
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 -- 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.
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.