The northwestern wolf (''Canis lupus occidentalis''), also known as the Mackenzie Valley wolf, Alaskan timber wolf, or Canadian timber wolf, is a

subspecies of gray wolf There are 38 subspecies of ''Canis lupus'' listed in the taxonomic authority ''Mammal Species of the World'' (2005, 3rd edition). These subspecies were named over the past 250 years, and since their naming, a number of them have gone extinct. T ...

in western

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...

. Arguably the largest grey wolf subspecies in the world, it ranges from

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U ...

, the upper Mackenzie River Valley; southward throughout the western Canadian provinces, aside from prairie landscapes in its southern portions, as well as the

Northwestern United States The Northwestern United States, also known as the American Northwest or simply the Northwest, is an informal geographic region of the United States. The region consistently includes the states of Oregon, Washington, Idaho, Montana and Wyoming. ...

.Mech, L. David (1981), ''The wolf: The Ecology and Behaviour of an Endangered Species'', University of Minnesota Press, p. 352,

Taxonomy

This wolf is recognized as a subspecies of ''Canis lupus'' in the taxonomic authority '' Mammal Species of the World'' (2005). The subspecies was first written of by Scottish naturalist Sir John Richardson in 1829. He chose to give it the name ''occidentalis'' in reference to its geographic location rather than label it by its color, as it was too variable to warrant such.Richardson, J. (1829
''Fauna boreali-americana, or, The zoology of the northern parts of British America''
London : J. Murray tc. pp. 60-65 According to one source,

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups ...

analyses of North American gray wolves show that there are three

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...

s corresponding to ''C. l. occidentalis'', '' C. l. nubilus'' and '' C. l. baileyi'', each one representing a separate invasion into North America from distinct Eurasian ancestors. ''C. l. occidentalis'', the most northwestern subspecies, is descended from the last gray wolves to colonize North America. It likely crossed into North America through the

Bering land bridge Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of ...

after the last ice age, displacing ''C. l. nubilus'' populations as it advanced, a process which has continued until present times. Along with '' C. l. nubilus'', ''C. l. occidentalis'' is the most widespread member of the five gray wolf subspecies in North America, with at least six different

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are al ...

Description

Northwestern wolves are one of the largest subspecies of wolves. In

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, for ...

, Canada, five adult females averaged 42.5 kg or 93.6 lbs with a range of 85 lbs to 100 lbs (38.6 - 45.4 kg) and ten adult males averaged 112.2 lbs or 51.7 kg with a range of 105 lbs to 135 lbs (47.6 - 61.2 kg), with a weight range for all adults of 38.6 kg to 61.2 kg (85 - 135 lbs). In

Yellowstone National Park Yellowstone National Park is an American national park located in the western United States, largely in the northwest corner of Wyoming and extending into Montana and Idaho. It was established by the 42nd U.S. Congress with the Yellowst ...

, adult females were average about 40 kg (90 lbs) and adult males average about 50 kg (110 lbs), with a mean adult body mass in winter of . More recent studies have reported the average range of height and weight in the north-west of the United States, both sexes were between tall at the shoulder. Here the weight of males was reported at between , while the females were reported at . The Northwestern wolf is also one of the longest wolf subspecies as his length usually ranges from 5 to 6 ft, and it can also reach as long as 7 ft (213 cm). In comparison, the mean adult weights of its nearest rivals in size, the

Eurasian wolf The Eurasian wolf (''Canis lupus lupus''), also known as the common wolf,Mech, L. David (1981), ''The Wolf: The Ecology and Behaviour of an Endangered Species'', University of Minnesota Press, p. 354, is a subspecies of grey wolf native to Euro ...

(''C. l. lupus'') and the Interior Alaskan wolf (''C. l. pambasileus''), was reported as and , respectively.Heptner, V. G. & Naumov, N. P. (1998)
Mammals of the Soviet Union Vol.II Part 1a, SIRENIA AND CARNIVORA (Sea cows; wolves and Bears)
', Science Publishers, Inc. USA., pp. 184-187, Sir John Richardson described the northwestern wolf as having a more robust build than the Eurasian wolf, with a larger, rounder head and a thicker, more obtuse muzzle. Its ears are also shorter, and its fur bushier.

Reintroduction

, artificially relocated northwestern wolves have been well-documented feeding on elk. They usually stampede the herd using pack teamwork to separate the younger elk from the adults. They also will charge young calves separated from their parents. Winter-weakened or sick elk also play an important part of Yellowstone wolf diets, and it is estimated that over 50 percent of winter-weakened or sick elk in Yellowstone are killed by wolves. Of these, about 12 percent of carcasses were scavenged by other predators, including

raven A raven is any of several larger-bodied bird species of the genus '' Corvus''. These species do not form a single taxonomic group within the genus. There is no consistent distinction between " crows" and "ravens", common names which are assigne ...

bald eagle The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as ...

s, black bears,

grizzly bear The grizzly bear (''Ursus arctos horribilis''), also known as the North American brown bear or simply grizzly, is a population or subspecies of the brown bear inhabiting North America. In addition to the mainland grizzly (''Ursus arctos horri ...

s, and

coyote The coyote (''Canis latrans'') is a species of canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological nich ...

s. In the same national park, wolves also prey on

bison Bison are large bovines in the genus ''Bison'' (Greek: "wild ox" (bison)) within the tribe Bovini. Two extant and numerous extinct species are recognised. Of the two surviving species, the American bison, ''B. bison'', found only in North A ...

, though such attacks usually involve sick animals or calves because healthy, adult bison can easily kill wolves with their hooves. Wolves are present in Canadian or British safari parks including

Longleat Longleat is an English stately home and the seat of the Marquess of Bath, Marquesses of Bath. A leading and early example of the Elizabethan era, Elizabethan prodigy house, it is adjacent to the village of Horningsham and near the towns of War ...

, Woburn, and Parc Omega.

References

External links

{{Taxonbar, from=Q3116028 Subspecies of Canis lupus Carnivorans of North America Mammals of Canada Mammals of the United States Wolves in the United States Fauna of the Northwestern United States Fauna of Alaska Mammals described in 1829