Ursus arctos middendorffi

Kodiak bear (Lisa Hupp / United States Fish and Wildlife Service)

Accepted scientific name:  Ursus arctos middendorffi (Clinton Hart Merriam, 1896)

Description:  The largest of the brown bear subspecies, similar in size to polar bears.  Males typically weigh from 480 to 535 kg and females 225 to 315 kg.  Males average around 245 cm at the shoulder.  The pelage ranges from blonde through a brownish orange (typically in females and bears in the south of the archipelago) to dark brown. Cubs often have a white ring around their necks which may remain for up to two years.

Range:  Found only on the islands of the Kodiak Archipelago, Southern Alaska, USA.  The archipelago stretches for 284 km from the Barren Islands in the north to Chirikof Island and the Semidi Islands in the south.  Kodiak island itself is the second largest island in the US covering almost 9,000 square km.  Two thirds of the island are within the  Kodiak National Wildlife Refuge.

Boundary Map of the Kodiak National Wildlife Refuge (coloured green on map) (United States Fish and Wildlife Service)

Habitat:  Kodiak bears are found throughout the archipelago, much of which is forested with numerous streams and around 40 small glaciers.  Kodiak Island is mountainous, heavily forested in the north and east, and largely treeless to the south.

Status:  Estimated numbers of bears exceed 3,500 and the population seems to be slowly increasing.

Life span:  Around 20 to 25 years in the wild; the oldest recorded male in the wild was 27 and the oldest female 34.  Around 25 percent of cubs die during their first three years of life.

Food:  Kodiak bears are omnivorous.  In spring and early summer they eat grasses and forbs along with carrion in the form of animals, such as deer and elk, that have died during the winter.  Various other plants, seeweeds, berries, nuts, roots, tubers and invertebrates are also eaten.  It is the five species of salmon found in the archipelago that form the most significant part of the diet.  These are available through most of the archipelago from May to September.

Behaviour:  Whilst some male bears my remain active thorughout the winter, most bears begin to enter their winter dens in late October.  Cubs are born in the den in January or February.  Litters are typically of two or three cubs.  The bears emerge from their dens in May or June.  The cubs will remain with their mother for three years during which time she will not become pregnant again.  Females usually become sexually mature at five years and mating usually takes place in May or June, with a single partner.  The mating pairs may remain together for as little as a couple of days or for as long as two weeks.  Except for this time and for mothers with cubs Kodiak bears are solitary animals although they do congregate in large groups where concentrated sources of food are available, notably during salmon runs.

Threats:.  Climate change, including possible effects upon salmon numbers; energy development projects and associated road-building; and increasing human activity, with a resultant increase in the likelihood of conflicts, are the main threats.  Hunting seems to be well controlled and within sustainable limits.

MORE INFORMATION

Management of Brown Bear Hunting on Kodiak Island, Alaska (2010) (pdf file).

Kodiak Archipelago Bear Conservation and Management Plan (2002) (summary and links to main pdf documents)

Climate change is shifting Kodiak bear feeding habits, study says (August 2017)

Page updated 22 August 2017

Save

Save

Close Menu