The all white Kermode or Spirit Bear (Ursus americanus kermodei) is the rarest of the North American bears and something of a "holy grail" for wildlife enthusiasts and photographers, and of great spiritual significance to the Pacific Northwest First Nations community who consider its appearance to be a very good omen.
A genetic variation of the ubiquitous North American Black Bear (Ursus americanus), the Spirit Bear is not an albino but rather the product of two parents possessing a common recessive gene. Because both parents must possess the gene in order to produce a white cub, it is possible for a white cub to have two black parents (if they both carry the gene), or a white parent to have a black cub (if it's mate does not carry the gene). Due to the delayed implantation common among bears which means a female may carry eggs fertilized by different males, a female carrying the gene may even have a mixture of black and white cubs in a single litter.
Spirit Bears can occur in any Black Bear population but are exceptionally rare, except on a cluster of heavily forested islands off the Central Coast of British Columbia where there is an unusually high concentration of the recessive gene. Here 1 in 10 black bears are born white, and on some of the islands the ratio may be as high as 1 in 4. Although otherwise identical in biology and behaviour to other black bears, there is scientific evidence to suggest that spirit bears have some inherent advantages due to their otherwise very conspicuous colouration. Studies have shown that spirit bears have a greater degree of success catching salmon in broad daylight than their black brethren. This seems to be a result of their lighter colouration and light reflection off the water's surface, and may account for adult white bears being larger on average that their black contemporaries in the same area.
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