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Ursus americanus

American Black Bear

Order: Carnivora
Family: Ursidae

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Image of Ursus americanus
Ursus americanus - eastern, black variant
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Conservation Status: Least Concern.


Most Black Bears hibernate for up to seven months, and do not eat, drink, urinate, or exercise the entire time. In the South, where plant food is available all year, not all bears hibernate—but pregnant females do. The female gives birth to 1-6 cubs (usually 2 or 3) in January, while she is deep asleep in her den. The newborn cubs snuggle next to her for warmth and nurse while she fasts. They grow from a birth weight of 200-450 g each (about 7-16 pounds) to the 2-5 kg they will weigh when the family leaves the den in the spring. Black Bears eat a little meat, and some insects, but they rely on fruit, nuts, and vegetation for the bulk of their nutritional needs. They are not all black. Most are, with brown muzzles, but in some western forests they are brown, cinnamon, or blond, and a few, in southern Alaska and British Columbia, are creamy white or bluish-gray.

Also known as:
Many common names are given to the many subspecies that have been described, such as: Olympic Black Bear, Glacier Bear, California Black Bear, Florida Black Bear.

Sexual Dimorphism:
The largest males may be nearly twice as heavy as the heaviest females.

Length:
Range: 1,44-2,000 mm males; 1,200-1,600 mm females

Weight:
Average: 120 kg males; 80 kg females
Range: 47-409 kg males; 39-236 kg females

References:

Pallas, P. S., 1770-1780.  Spicilegia zoologica, quibus novae imprimus et obscurae animalium species iconibus, descriptionibus atque commentariis illustrantur cura P.S. Pallas. [fasc. 11-12 imprint 1777-78; fasc. 13 imprint 1779; fasc. 14 imprint 1780]. Berolini, prostant apud Gottl. August. Langed, 14 fasc in 2 volumes.

Links:

Mammal Species of the World

Distribution of Ursus americanus

Image of Ursus americanus
Ursus americanus - western, brown variant
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Image of Ursus americanus
Ursus americanus - other variations: Glacier, upper left; Kermode, upper right; blond, lower left; cinnamon, lower right
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Image of Ursus americanus
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Skull of Ursus americanus
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