POLAR WILDLIFE
Polar regions : The Arctic and Antarctic Circles are defined as those parts of the planet that experience 24 hours of daylight and 24 hours of darkness for atleast one day in the year . The Arctic and Antarctic are totally different from each other . The Arctic is a frozen sea surrounded by land ; the Antarctic is an ice - covered continent surrounded by sea .
MAMMALS : The Arctic is warmer than the Antarctic and therefore has more vegetation. Some herbivorous land mammals can survive here ; other mammals depend on the sea for their food , either directly or indirectly . The Antarctic mammals are all aquatic . Any carnivorous land mammals would create havoc among millions of penguins that live there .
Polar bear : The polar bear has black skin to absorb heat , and hollow hairs for added insulation . It also has a thick layer of fat
beneath the skin and is able to go for long periods without feeding by living on this fat.
Seals : Seals are adapted to life in the sea and spend much of their time in the water , often
under the ice . They haul out to rest and breed . In the Arctic , seals are hunted by polar bears . Antarctic seals are prey for leopard seals and killer whales .
Arctic fox : Smaller than the red fox , the Arctic fox changes colour from white to
grey-brown in the summer . It has a very thick coat and is extremely tolerant of the cold . Its diet is very varied and includes bird's eggs , birds , lemmings and carrion .
Musk oxen : These are not oxen but members of the goat antelope family . They
have long black fur which absorbs heat . They are known for forming defensive circles when danger threatens , so that predators are faced with a barrier of horns .
Arctic hare : The Arctic hare matches its surrounding by changing colour from white
in winter to brown in summer and is then more difficult for predators to spot . Unusually for hares , it digs burrows and these are often used by its young for shelter.
BIRDS : Antarctic birds fall into two main categories . They are either flightless like penguins , or magnificent fliers like albatrosses .
Penguins : Several species of these flightless birds breed in their millions in the Antarctic.
They are kept warm by their dense plumage and by a layer of fat under their skin. They
go without food for long periods while incubating eggs and protecting their young .
Snowy owl : This large white owl is solitary and active mainly by day . It chases other
other birds and also takes prey as large as Arctic hares and eider ducks . It perches on low branches to rest or preen , but nests on the ground .
Gulls : The only gull that lives and breeds in the Antarctic is the kelp gull , which feeds
mostly on limpets and krill . A number of other gull species breed in the Arctic in colonies on the tundra or on the sea cliffs . These fly south to live in warmer climates for most of the year .
Little auk : One of the smallest sea birds , the little auk nests in large colonies on the
Arctic cliffs . Like other auks , it has narrow wings and feet set well back on its body . It specializes in diving for its food .
PLANTS : It is a real struggle for plants to survive in such extreme climates . There are only two species of flowering plants in Antarctica , although the more maritime climate of the Arctic encourages more plant species . All tend to be low - growing as this gives them shelter from the strong winds . Mosses and lichens are the hardiest plants in polar regions .
Purple saxifrage : This creeping plant is generally found sheltering among rocks
in the Arctic . Its beautiful purple flowers bloom almost as soon as the snow has melted , to make the most of the short spring and summer . They add a splash of colour to an often drab landscape .
Arctic willow : This is a low - growing shrub that grows in tundra swamps and wet
ground . It sends out long woody stems along the ground . In the northern spring , it has small catkins that appear out of scale with the rest of the plant . Arctic willow and its close relative Alaska willow are favourite foods of moose .
Hairgrass : This and Antarctic pearlwort are the only two flowering plants found in the
Antarctic . Hairgrass grows in low mats and is found only in those areas near the coast from which the snow recedes in spring and where the temperature is sufficiently high .
Lichens : Many species of these hardy plants grow in both north and south polar regions ,
where they can thrive in the unpolluted air . Often colourful , they generally occur as encrustations on the rocks . They may be fertilized by droppings from nesting birds .
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