Dall Sheep

Dall Sheep

Taxobox
name = Dall Sheep
status = LR/lc | status_system = IUCN2.3
status_ref = [IUCN2006|assessors=Caprinae Specialist Group|year=2000|id=39250|title=Ovis dalli|downloaded=12 May 2006 ]



image_width = 250px
image_caption = Dall Sheep ram at the Alaska Zoo in Anchorage, Alaska.
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Artiodactyla
familia = Bovidae
subfamilia = Caprinae
genus = "Ovis"
species = "O. dalli"
binomial = "Ovis dalli"
binomial_authority = Nelson, 1884

The Dall Sheep (originally Dall's Sheep, sometimes called Thinhorn Sheep), "Ovis dalli", is a wild sheep of the mountainous regions of northwest North America, ranging from white to slate brown and having curved yellowish brown horns. There are two putative subspecies: the northern Dall Sheep proper ("Ovis dalli dalli") which is almost pure white, and the more southern Stone Sheep (also spelled Stone's Sheep) ("Ovis dalli stonei"), which is a slaty brown with some white patches on the rump and inside the hind legs.

Research has shown that the use of these subspecies designations is questionable. Complete colour integradation occurs between white and dark morphs of the species with intermediately coloured populations, called Fannin's Sheep ("Ovis dalli fannini"), found in the Pelly Mountains and Ogilvie Mountains of Yukon Territory.Sheldon, C. 1911. "The Wilderness of the Upper Yukon". First edition. Charles Scribner’s Sons, New York.] Mitochondrial DNA evidence has shown no molecular division along current subspecies boundariesLoehr, J., K. Worley, A. Grapputo, J. Carey, A. Veitch and D. W. Coltman. (2006) "Evidence for cryptic glacial refugia from North American mountain sheep mitochondrial DNA", Journal of Evolutionary Biology, 19:419-430.] , although evidence from nuclear DNA may provide some support.Worley, K., Strobeck, C., Arthur, S., Carey, J., Schwantje, H., Veitch, A. & Coltman, D.W. (2004). "Population genetic structure of North American thinhorn sheep Ovis dalli," Molcular Ecology 13: 2545–2556.] Also at the species level current taxonomy is questionable because hybrdization between "Ovis dalli" and "Ovis canadensis" has been recorded in recent evolutionary history.Loehr, J., K. Worley, A. Grapputo, J. Carey, A. Veitch and D. W. Coltman. (2006) "Evidence for cryptic glacial refugia from North American mountain sheep mitochondrial DNA", Journal of Evolutionary Biology, 19:419-430.]

The latter half of the Latin binomial "dalli" is derived from William Healey Dall (1845-1927), an American naturalist. The common name Dall Sheep or Dall's Sheep is often used to refer to the species "Ovis dalli". An alternative use of common name terminology is that Thinhorn Sheep refers to the species "Ovis dalli", while Dall's Sheep and Stone's Sheep refer to subspecies "Ovis dalli dalli" and "Ovis dalli stonei".

The sheep inhabit the subarctic mountain ranges of Alaska, the Yukon Territory, the Mackenzie Mountains in the western Northwest Territories, and northern British Columbia. Dall sheep are found in relatively dry country and try to stay in a special combination of open alpine ridges, meadows, and steep slopes with extremely rugged ground in the immediate vicinity, in order to escape from predators that cannot travel quickly through such terrain.

Male Dall Sheep have thick curling horns. The females have shorter, more slender, slightly curved horns. Males live in bands which seldom associate with female groups except during the mating season in late November and early December. Lambs are born in May.

During the summer when food is abundant, the sheep eat a wide variety of plants. During the winter diet is much more limited and consists primarily of dry, frozen grass and sedge stems available when snow is blown off, lichen and moss. Many Dall Sheep populations visit mineral licks during the spring and often travel many miles to eat the soil around the licks.

The primary predators of Dall Sheep are wolves, coyotes, black bears, and grizzly bears; golden eagles are predators of the young.

Dall Sheep can often be observed along the Alaska Highway at Muncho Lake and at Sheep Mountain in Kluane National Park and Reserve, as well as near Faro, Yukon (Fannin's Sheep).

Notes

References

*A.W.F. Banfield (1974). "The Mammals of Canada". University of Toronto Press. ISBN 0-8020-2137-9


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  • Dall sheep — ram at the Alaska Zoo in Anchorage, Alaska. Conservation status …   Wikipedia

  • Dall sheep — [dôl] n. a wild sheep (Ovis dalli) with white hair and long spiral horns, living in the mountains of NW North America: also Dall s sheep * * *       (Ovis dalli), species of bighorn (bighorn sheep) (q.v.). * * * …   Universalium

  • Dall sheep — [dôl] n. a wild sheep (Ovis dalli) with white hair and long spiral horns, living in the mountains of NW North America: also Dall s sheep …   English World dictionary

  • Dall sheep — noun large white wild sheep of northwestern Canada and Alaska • Syn: ↑Dall s sheep, ↑white sheep, ↑Ovis montana dalli • Hypernyms: ↑wild sheep • Member Holonyms: ↑Ovis, ↑genus Ovis …   Useful english dictionary

  • Dall sheep — noun Etymology: William H. Dall died 1927 American naturalist Date: 1887 a large white wild sheep (Ovis dalli) of Alaska and northern British Columbia called also Dall s sheep …   New Collegiate Dictionary

  • Dall — Dall, as a person, may refer to: Bobby Dall (b.1958), an American musician Cindy Dall, a musician Curtis Bean Dall (1896 1991), an American businessman and author James Kyle Dall, first headmaster of Elmfield College John Dall (1918 1971), an… …   Wikipedia

  • Dall's sheep — Dall s′ sheep′ [[t]dɔlz[/t]] also Dall′ sheep′ n. mam a white haired wild mountain sheep, Ovis dalli, of NW North America • Etymology: 1905–10; after William H. Dall (1845–1927), U.S. naturalist …   From formal English to slang

  • Dall's sheep — noun large white wild sheep of northwestern Canada and Alaska • Syn: ↑Dall sheep, ↑white sheep, ↑Ovis montana dalli • Hypernyms: ↑wild sheep • Member Holonyms: ↑Ovis, ↑genus Ovis …   Useful english dictionary

  • Dall's sheep — /dawlz/ a white haired wild sheep, Ovis dalli, of mountainous regions of northwestern North America, having curved horns. Also, Dall sheep. [1905 10; named after William H. Dall (1845 1927), American naturalist] * * * …   Universalium

  • Dall's sheep — noun see Dall sheep …   New Collegiate Dictionary

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