POLAR BEARS-Biology Project

8/8/2019 POLAR BEARS-Biology Project

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POLAR BEARSPolar bears, the creamy white furry animals found in the Arctic region, areplummeting in number. Climate change, pollution, poaching, etc. has forced

these bears to be listed as endangered species. The article answers thequestion 'are polar bears endangered?'

Polar Bears, also known as 'sea bears', are the closest relative of the brownbear. Adult male polar bears weigh between 550-1700 pounds, and can

measure from 8-10 feet in height. On the other hand, the females are smaller,

weighing between 200-700 pounds. They measure from 6-8 feet in height. Polarbears can live up to 15-18 years on average in the wild, and up to 30 years incaptivity. Scientists have recognized 19 distinct populations of polar bears;

however, no sub species have been found. The scientific name of the polar bearis Ursus maritimus, and its scientific classification is as follows:

Kingdom: AnimaliaPhylum: ChordataClass: MammaliaOrder: CarnivoraFamily: UrsidaeGenus: Ursus

Species:maritimus



Table of Contents

Location(habitat) of Polar Bears

Distribution of Polar Bears

Description Size and Diet

Why Polar Bears are Endangered

Importance of Polar Bears

Pictures of Polar Bears



LOCATION OF POLAR

BEARSPolar bears are found throughout thecircumpolar Arctic on pack ice, along or near

coasts, and on islands.

Sea ice is more than a simple platform: it is an

entire ecosystem inhabited by plankton andmicro-organisms, which support a rich foodchain that nourishes seals that in turn become

prey for polar bears.

As their ice habitat shrinks bears in thesouthern limits of the Arctic - especially around

Hudson Bay, Canada - face a grave threat totheir survival.



DISTRIBUTION OF POLAR

BEARSCurrent bear populations

20-25,000 polar bears worldwide

Approximately 19 distinct sub-populations

60% of these are in Canada

Tracks have been reported as far north as the

pole

Few scientists believe few bears travel beyond

82° north latitude. This is because the northern

Arctic Ocean has little food for them.



DESCRIPTIONPolar bears are large bears. Theyhave strong legs with large,flattened feet that help withwalking on ice and swimming.The wide paws prevent sea ice

from breaking by distributingweight while the bear is walking.In addition, the wide paws serveas paddles to help polar bearsswim faster. They are also

partially webbed.

Many of the polar bear's physicaladaptations help maintain bodyheat:



CONTDFur covers the entire body, even the feet, to help keep thebear warm in the bitterly cold climate of the Arctic.

The fur has two layers--one for trapping in heat close to thebody and another for trapping heat and repelling water.

The outer layer of fur is hollow and reflects light giving the

fur a white color.The white fur helps the bear camouflage in the icy andsnowy habitat.

In contrast to the white fur, the skin is black. The black skinmore readily absorbs sunlight, which helps to keep the bearwarm. A polar bear's tongue is also black.

Polar bears have a layer of blubber below the surface of theskin. The blubber acts as insulation on the body to trap heat.This is especially important while swimming.



SIZE AND DIETSize: Polar bears are one of the largest land mammals onEarth. They're about 7-9 feet long. Male polar bears are much

larger than the females. An average male can weigh over a ton approximately 800-1,500 pounds. The females are usuallyone-third of the weight of the males, from 300-550 pounds.

Diet: Polar bears are carnivores. They eat ringed and beardedseals, but they have been known to eat walruses, other

species of seals, belugas and the carcasses of larger whales. If desperate, a polar bear will eat whatever meat it can find.

Polar bears hunt seals by waiting for the seal to come near the

surface of sea ice to breathe. When the seal nears the surface,the polar bear bites or grabs the seal and pulls it onto land to

feed. In the Arctic, polar bears are at the top of the foodchain.



WHY POLAR BEARS ARE

END

ANGERED

Species which are on the verge of extinction areclassified as endangered species

Global warming has taken a toll on the populationnumbers of polar bears. Today, polar bears are listed asthreatened species under the Endangered Species Actof 1973. In 2005, the polar bear was reclassified as

'vulnerable' on the IUCN World Conservation Union'sRed List of Threatened Species, noting that polar bearscould become extinct if the sea ice changes continue.



CONTD Increase in temperature in the Arctic regions due to

global warming has caused the ice to melt. Ice is thehabitat of these polar bears, which they use forhunting, traveling and mating. In some areas, bears

spend the summer months on land and fast until ice isformed in the fall. They then use the ice as a rostrum tohunt seals in the seas. According to certain studiesrelated to polar bear population in Canada, the periodof fasting has increased by three weeks since the1970s. Moreover, the population has declined by 15%in the past ten years. The US Minerals ManagementService in northern Alaska has reported that somepolar bears have drowned in the attempt to swim longdistances between land and ice



CONTD Global warming has caused other animals to die in the

Arctic region, which is why polar bears have nothing to eat.Sadly, the only food source polar bears are left with aretheir own kind, which further reduces the number of polar

bears. The answer to 'why are polar bears dying so rapidly?'can also be attributed to human beings. Humans have beenhunting polar bears for fur and other needs. Scientists statethat if the current global warming trends continue in theArctic region, then the consequence of it will bedisappearance of two-thirds of the polar bear population

by 2050. On May 14, 2008, the U.S. Department of theInterior announced its decision about classifying polarbears as 'threatened under the Endangered Species Act.



CONTD It is necessary to protect the shrinking sea ice

habitat for polar bears whose existence has

been threatened. The other reasons for polar

bears becoming threatened are poaching,industrial disturbances and pollution.



IMPORTANCE OF POLAR

BEARS Among all the Arctic wildlife species, the polar bear isthe most iconic

The polar bear is the Arctic regions top predator and

indicate health of an ecosystem, specifically behaviorof marine ecosystems.

Locals from arctic regions, use polar bear hide asclothing rugs and blankets.

The hollow guard hairs of the polar bear fur can be soldfor fly tying(the process of producing an artificial fly tobe used by anglers to catch fish via means of fly fishing)

Polar beat meat serves as food for natives.



Pictures of Polar Bears







Documents

POLAR BEARS-Biology Project