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Kodiak Brown Bear

Ursus arctos middendorff
Sow
The interior grizzly and the coastal brown bear (including Kodiak brown bears) are both scientifically named "Ursus arctos". The main difference in the two is related to geographical range. The coastal brown bear is found mainly in maritime areas along the coast of Alaska where there are abundant salmon resources, while the interior grizzly is found mainly within the interior areas of Alaska and feeds primarily on non-salmonid resources. The Kodiak brown bear is classified as "Ursus arctos middendorffi" and is considered a distinct subspecies. This subspecies classification is based mainly upon morphological characteristics and geographic isolation. The black bear, "Ursus americanus", is found in some coastal areas and interior areas of Alaska, but not on Kodiak.

The population of brown bears on the Kodiak Archipelago is estimated at approximately 3,500 animals of which approximately 2,300 are found within the boundaries of the Kodiak National Wildlife Refuge. Approximately 180 to 200 of these bears use the 236 mile square Karluk Lake drainage, one of the densest populations of bears in the world.
Life History of the Kodiak Brown Bear

Size range for females is from 400 to 700 pounds and for males 600 to 1,400 pounds. There can be a difference of 20 to 30 percent gain in weight between when they emerge from dens in the spring and when they den up in the late fall.

The oldest recorded bear was a 35 year-old female. The initial breeding age is at approximately six years-old and they will usually have two cubs in the first litter and can have up to four in subsequent litters. The average litter size is 2.3 cubs. In general, most cubs remain with their mothers until they are 2-3 years-old.

Kodiak bears breed in spring (May to early-June) and an adult female may mate with several adult males. Cubs are born in the den the following winter ( January or February) due to delayed implantation, and each sibling cub could be from a different father.

In general, after leaving the den in the spring, bears move to lower elevations where they may feed on carrion, roots or other freshly emergent vegetation. As spring progresses, they feed in the high alpine areas below the snow-line on succulent forbs and sedges. During summer, many bears move to, and stay near, streams when salmon are available in local streams. Between July and September, bears routinely supplement their diet with berries—especially salmonberry, elderberry and crowberry. After berry availability declines in September, most bear use focuses on streams which provide late run salmon. Some bears may prey on deer, but it depends on the individual bear.

Brown bears den in early-to-late November depending on the geographical location within the refuge. Some bears may move den sites one or more times or not den up at all. In addition, some non-denning bears that inhabit lowland areas such as the Aliulik Peninsula on the south end of Kodiak Island switch their foraging efforts to the marine shoreline.

The population of brown bears on the Kodiak Archipelago is estimated at approximately 3,500 animals of which about 2,300 of these are found within the boundaries of the Kodiak National Wildlife Refuge. Approximately 180 to 200 of these bears use the 236 mile square Karluk Lake drainage, one of the densest populations in the world

Facts About Kodiak Brown Bear

Diet:
Omnivore

Average Life Span:
28 years

Size:
400-700 lbs (sows)
600-1400 lbs (boars)
Last Updated: Apr 07, 2012
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