Polar Bears Cecilia Mak Jacqueline Wong Raymond Yang Helen Li Period 3, Life Science MS. KWON

Classification  KINGDOM: Animalia  PHYLUM: Chordata  CLASS: Mammalia  ORDER: Carnivora  FAMILY: Ursidae  GENUS SPECIES: Ursus (bear) maritimus (sea)

Physical Characteristics  2.Male polar bears (boars) grow two to three times the size of females (sows). Boars weigh about 350 to more than 650 kg (772-1,433 lb.) and are about 2.5 to 3 m ( ft.) long. 3.Sows weigh about 150 to 250 kg ( lb.) and are about 1.8 to 2.5 m ( ft.) long. Pregnant females can weigh as much as 500 kg (1,102 lb.).  Have more slender bodeies and longer necks/heads than other bears.  The hind limbs are longer than the forelimbs. Polar bears have large paws compared to body size, reaching 30 cm (12 in.) in diameter.  A polar bear's head is oblong and relatively small compared to body size. The muzzle is elongated with a "Roman-nosed" (slightly arched) snout. 2.The nose is broad and black. Teeth.Polar bears have 42 teeth, which they use for catching food and for aggressive behaviorThe tail is small, about 7 to 12 cm ( in.) long.  Polar bears are completely furred except for the nose and footpads. Polar bears completely molt (shed and replace their fur) annually, in May or June. The molt can last several weeks. The coat can vary from pure white to yellow to light brown depending upon season and angle of light  A polar bear's skin, visible only on the nose and footpads, is black. The black color enables the bear to absorb sunlight energy to warm its body.

Behavioral Characteristics  Polar bears are most active the first third of the day and least active the final third of the day.  When not hunting, polar bears are often sleeping or resting.  Polar bear mothers are attentive, frequently touching and grooming their cubs.  Polar bear mothers are attentive, frequently touching and grooming their cubs.  Polar bear breeding pairs remain together for one week or more, mating several times.  Polar bear breeding pairs remain together for one week or more, mating several times.  Aggression occurs between males during the breeding season and when males attempt to steal food caught by other polar bears.  Aggression occurs between males during the breeding season and when males attempt to steal food caught by other polar bears.  Play fighting has been observed between aggregating subadult and adult male polar bears.

Food Source  The bears eat mainly seals  They also eat reindeer, fish, small rodents, ducks, eggs, and birds  They still hunt  They need 2kg per day to survive  They use their claws and teeth  Skin and fat are eaten first, then meat

Habitat  Polar bears live in the entire circumpolar Arctic.  They are adapted to live in water and on land.  They are adapted to live in water and on land.  Unlike, most bears they are excellent swimmers.  Over 40 percent of all polar bears living today live in Northern Canada.  They stay in the ice packs of their environment because it allows them to stay near their food source  When summer comes, they swim many miles to remain on ice.

Adaptations  Polar bears swim no more than 6 m. to hunt for food  Their hind feet and legs are called rudders  While swimming, nostrils are closed  The bear shakes itself after swimming  Moves slowly to prevent overheating  Their blubber is 11 cm. thick

Interesting Facts  Sometimes polar bears go into towns and villages. They can break into buildings to find food.  Polar bears eat every part of the seal, but the meat.  Bears that raid towns are not shot, but caught and taken back to the wild.  Many countries have laws to protect polar bears,but hunters still kill them.  They search for food at the garbage dump outside of town.  Polar bears are found near the town of Churchill ( Canada ).

Citations  bytes/animalia/eumetazoa/coelomates/deuterostomes/ch ordata/craniata/mammalia/carnivora/polar-bear.htm bytes/animalia/eumetazoa/coelomates/deuterostomes/ch ordata/craniata/mammalia/carnivora/polar-bear.htm bytes/animalia/eumetazoa/coelomates/deuterostomes/ch ordata/craniata/mammalia/carnivora/polar-bear.htm  l l l    bear/behavior.htm  bear/physical-characteristics.htm