Polar Bear (Ursus maritimus)

         

Class: Mammalia
Order: Carnivora
Family:    Ursidae
Size:    Height: 6 to 11 feet (1.8 to 3.4 m) when standing
Weight: 200 to 1,600 pounds (91 to 726 kg)
Diet: Mainly seals, but also ducks, mussels, walrus, lemmings, berries and seaweed
Distribution: Alaska, Canada, Greenland, Norway and Russia
Young:  1 litter (1 to 4 cubs, but usually 2) every 2 to 4 years
Animal Predators:  Killer whales, male walruses and wolves, but these are rare occurrences
IUCN Status: Lower Risk, Conservation Dependent
Terms: Young: Cub
Lifespan: 25 to 30 years in the wild, up to 45 years in captivity

 

Facts/Trivia:

·        The scientific name, Ursus maritimus, is Latin for “sea bear.

·        Polar bears are larger than grizzlies.

·        When emerging from water, polar bears shake the water from their fur so it does not freeze.

 

Description

Polar bears have a large, stocky body. They tend to have a smaller head than those of other bears. Their fur is creamy white and their skin and claws are black. Females are smaller than males. Their feet are thickly furred to help keep them warm while walking over snow and ice. Polar bears have excellent eyesight. 

 

Habitat

Polar bears tend to have much larger territories than any other bears. Although they typically stay within a home range of a few hundred square miles, polar bears have been known to travel as far as 3,000 miles across the tundra in search of food. They are not territorial and do not mind other bears being in close proximity, though they probably will not interact. 

 

Feeding Habits

Seals are the favourite meal of polar bears—they will go to great lengths to capture a seal. Although seals are better swimmers, thanks to their white coats which provide camouflage, polar bears are able to trick seals by pretending to be chunks of ice, until they are close enough to attack. The bears eat only the fat and skin of the seals, while the rest gets eaten by arctic foxes and ravens. Other food for polar bears includes ducks, mussels, walrus and lemmings, as well as berries, grass and seaweed. Most polar bears are extremely fastidious and lick their paws after every meal or, if water is near, they will wash them. They also roll in snow to remove any food or blood that may have fallen on their fur. 

 

Reproduction

Although polar bears do not usually hibernate, they do create winter dens and sometimes sleep whole days through—115 to 125 days for non-pregnant females and 60 days for males and pregnant females. Mating occurs in the spring, and the litters are born from October to January. Cubs weigh one-and-a-half pounds (0.7 kg) at birth and remain with their mothers for two-and-a-half years, returning to her den for the first winter following their birth. Mothers and cubs may group together, but will stay away from males, who may harm the cubs. 

 

Behaviour

Powerful swimmers, polar bears can go speeds of up to five miles per hour using only their front legs. They are able to dive and can remain underwater for two full minutes. They are also fast runners over short distances and can run as fast as horses. Polar bears may become aggressive when confronted by people but usually the two do not live in the same area. Polar bears can be extremely playful, both with each other (as in a mother and her cubs) and sometimes even with other species, such as dogs. 

 

Conservation

Polar bears are listed as being of Special Concern by the Canadian Wildlife Service. In Manitoba, Polar Bears are listed as a protected species under the Wildlife Act and there is no hunting season. Canada, the U.S., Denmark, Norway, and the U.S.S.R. signed an International Agreement on the Conservation of Polar Bears in 1973, which came into effect in 1976.

 

Sources

http://www.speciesatrisk.gc.ca/Species/English/SearchDetail.cfm?SpeciesID=167

http://www.zooregon.org/cards/Bears/bear.polar.htm

http://animaldiversity.ummz.umich.edu/

http://www.zoo-keeper.co.uk/polar_bear.htm

http://www.xmission.com/~hoglezoo/mammals/polarbr.htm

http://www.il-st-acad-sci.org/mammals/bear1002.html

http://www.polarbearsalive.org/faq.htm

http://www.cws-scf.ec.gc.ca/hww-fap/plbear/pbear.html

http://www.polarbear.org.uk/cgi-bin/viewpics?category=WILD

Polar Bear Wildlife Fact File, IM Pub, US

International Wildlife, September/October 1989