J. A. Allen de-emphasized coat colouration in 1909, suggesting that so far as the pelage is concerned, these skins might readily be looked upon as albinistic examples of a normally dark-coloured bear. The skull

Дата канвертавання27.04.2016
Памер9.26 Kb.
Taxonomy of the Kermode Bear
Written by Tony Hamilton, B.C. Ministry of Environment (Tony.Hamilton@gems3.gov.bc.ca)
The white colour phase has long been recognized by the aboriginal peoples of the Northwest Coast. In 'Somewhere Between' (Carter 19**), there is an account of the Tsimpshian legend of the white bear. The Gitksan and N'ishga also held 'Moksgm'ol' in high regard (Robinson 1991). Ethnologists Frans Boas and Maurius Barbeau recorded stories of white bears being associcated with great hunting prowess and with helping people faced with hunger (Robinson 1991).
The scientific world first learned of Kermode bears from William T. Hornaday (Hornaday 1905). Hornaday had come to Canada in November 1900 and "while making an examination of the skins of North American bears that were to be found in Victoria, British Columbia, the writer found a very strange specimen in the possession of Mr. J. Boskowitz, a dealer in raw furs. The skin was of a creamy-white color, and very small. Mr. Boskowitz reported that it had come to him from the Nass River country, and that he had previously received four or five similar skins from the same locality" (Hornaday 1905). Hornaday boldly concluded that "there is not the slightest probability that albinism is rampant among any of the known species of bears of North America; and it is safe to assume that these specimens do not owe their color to a continuous series of freaks of nature. There is no escape from the conclusion that a hitherto unknown species of white bear, of very small size, inhabits the west-central portion of British Columbia" (Hornaday 1905). Hornaday named the "new species" Ursus kermodei. "In recognition of his successful efforts in securing three of these specimens, the new species is named in honor of Mr. Francis Kermode". Kermode was an employee of the Provincial Museum who was subsequently promoted to Curator in 1904.
J.A. Allen de-emphasized coat colouration in 1909, suggesting that "so far as the pelage is concerned, these skins might readily be looked upon as albinistic examples of a normally dark-coloured bear. The skull however, presents distinctive characters of some importance, warranting the recognition, for the present at least, of Ursus kermodei as a stongly marked form, and possibly as a 'good species'"(Allen 1909).
In 1928 E. Raymond Hall confirmed Allen's assertion that skull characteristics of the specimens he examined were unique (Hall 1928). Hall (1928) examined a total of five skulls (2 female, 3 male - all from white morphs) and concluded that "as compared with U. a. vancouveri, the skull of U. kermodei is smaller and narrower, the rostrum is relatively more expanded anteriorly above the canines, the frontal region is less inflated, and the dorsal outline is longitudinally less convex" (Hall 1928). However, Hall did not believe these differences warranted species status, and consequently changed the taxonomic name to Ursus americanus kermodei. Hall's assertation is unequivocal: "as clearly shown by the skull and dentition, Ursus kermodei is a member of the Ursus (Euarctos) americanus group" and "although the writer has seen skulls of only white specimens from the range of U. a. kermodei he infers that the cranial characteristics of the black and cinnamon bears there are the same and that the white color is merely a colour phase and in no wise a specific or subspecific character" (Hall 1928). Note that Hall was under the impression that brown morph black bears were present in the range of U. a. kermodei. While some brown coloured black bears are present in Northwestern BC, I know of no occurrences of the true "cinnamon" colouration in that area of the province.
Hall's taxonomic recognition - that of a distinct subspecies occupying a defined geographic area in Northwestern BC that includes all colour morphs of black bears on the basis of cranial and dental characteristics alone - remains the same to this day (see Nagorsen 1990).
Perhaps there has been too much historic emphasis on taxonomic "splitting" of black bears in British Columbia. Dave Nagorsen, mammal curator at the Royal BC Museum, suggests that "from a population differentiation perspective (at least cranial morphology) the most distinct black bears in North America are from the Queen Charlottes (spp. carlottae). The kermode bear (spp. kermodei) is very weakly defined and may be indistinquishable from the interior race cinnamomum" (Nargorsen, pers. comm.).
Unfortunately, the genetics of coat colouration and subspecies taxonomy are commonly confused. A black bear (Ursus americanus kermodei) of any colour morph in a part of Northwestern BC is a 'Kermode' from a strictly taxonomic standpoint. However, most people refer to only the white morphs as Kermode bears. The few records of white bears from Northeastern BC (centred around the Liard River Hotsprings and Toad River Provincial Parks) are also suspected to be a result of the same gene mutation - indicating that the mutation occurs over a much broader geographical area than commonly thought (see Massier 1991 for a photo of a white bear from Toad River). Dr. Ian McTaggart Cowan appears to confirm the occurrence of white bears outside of Northwestern B.C. in his 1938 paper and implied that the early collecting expeditions were detrimental to the expression of the mutation (Cowan 1938). "The recognized tendency for insular populations to produce a greater than normal percentage of albinistic individuals further led to the erroneous description of Ursus kermodei as a white bear. The resulting publicity led to a selective removal of the albinos, with the result that white individuals are now no more abundant in the range of kermodei than elsewhere in British Columbia (Cowan 1938)." To further confound the issue, "true" albino black bears (with pink, light sensitive eyes) have been recorded. One of these bears was found starving near Bella Coola in 1992, captured and shipped to the Vancouver Game Farm where it is still alive.
The issue of taxonomics vs. coat colour is confused elsewhere in B.C. There are a few confirmed records of 'glacier' or 'blue' bears from the extreme northwest of the province (Tatshenshini area). Ursus americanus emmonsii is a recognized subspecies that includes the blue or glacier morph but also includes the black morphs in that vicinity (see Nagorsen 1990). 'Pinto' coloured bears have been sighted on the coast (Robinson 1991). And finally, blond or 'honey' bears have been recorded in North Eastern BC (see Novak et. al. 1987 for a painting of 'honey' coat colouration).
Current work by Drs. Ben Koop and Tom Reimchen and their students at the University of Victoria may clear up the confusion about black bear taxonomy in coastal B.C. Using DNA analysis, these researchers are testing the hypothesis that some black bears in BC may have survived through the last glaciation in the Queen Charlotte Islands (a glacier-free refugia) and subsequently re-populated the mainland coast. Other coastal black bears may have spread onto the coast from the east and south (Koop, pers. comm.).

База данных защищена авторским правом ©shkola.of.by 2016
звярнуцца да адміністрацыі

    Галоўная старонка