POLAR BEARS

Vocabulary-nouns

ADULTMALEFEMALECOASTLINESEALRUDDERDENSNOWSHOESHABITATBLOWFURCUBSKIN

DOSPĚLÝSAMECSAMICEPOBŘEŽÍTULEŇKORMIDLODOUPĚSNĚŽNICEOBLAST VÝSKYTUÚDERSRSTMLÁDĚPOKOŽKA

Vocabulary – adjectives/verbs

BLINDDEAFHAIRLESSSLIPPERYPADDLECOME ASHOREHUNT FOR PREY

SLEPÝHLUCHÝBEZ SRSTIKLUZKÝPÁDLOVADOSTAT SE NA BŘEHLOVIT KOŘIST

Polar bears habitual range

Five nations have polar bear populations: the United States (Alaska), Canada, Russia, Greenland, and Norway.

Basic factssea bear, started to evolve about five million

years ago from brown bear ancestors

weigh

length

fur

skin

295 - 490 kg

2.5 – 3 metres

thick-10cm fat layeryellowish or white

black to absorb heat

Communication

Polar bears use a combination of body languageand vocalizations to communicate.Head wagging from side to side often occurs when polar bears want to play. Adult bears initiate play—which is actually ritualized fighting or mock battling—by standing on their hind legs, chin lowered to their chests, and front paws hanging by their sides

Nose-to-nose greetings are the way a bear asks another bear for something, such as food. The guest bear will approach slowly, circle around a carcass, and then meekly touch the other bear's nose. Bears who use proper manners are often allowed to share a kill.Attacking polar bears charge forward with heads down and ears laid back.

Chuffing sounds are a response to stress, often heard when a mother bear is worried for her cubs' safety. Mother bears scold cubs with a low growl or soft cuff. When a male approaches a female with cubs, she rushes toward him with her head lowered.Hissing and snorting and a lowered head all signify aggression.Loud roars or growls communicate anger.Deep growls are warnings, perhaps in defense of a food source.

FUR

Polar bears look whitest when they are clean and in sunlight, especially just after the molt period, which usually begins in spring and is complete by late summer. Before molting, oils from the seals they eat can make them look yellow

Molt period – línání,pelíchání

CUBS

Usually 2 (1 or triplets)stays with mother for 3 monthsweigh 0.5-1kghairless ,blind,deaf

Usually 2 (1 or triplets)stays with mother for 3 monthsweigh 0.5-1kghairless ,blind,deaf

CUBS

For at least 20 months, cubs drink their mother's milk and depend on her for survival. Her success at hunting is critical for her own needs and for teaching cubs to find food for themselves.In the Low Arctic weaning occurs as cubs approach their second birthday. Cubs in the High Arctic generally receive an additional year of care.

FOODwalrus whale polar fox seal

GLOBAL WARMING

• Floods. Droughts. Heat waves. Monster tornadoes

Floods. Droughts(sucho). Heat waves(vlny veder). Monster tornadoes. Climate change is not just about polar bears, the iconic symbol of a melting(tající) Arctic

How are polar bears affected by global

warming?Polar bears have evolved for a life on the sea ice, which they rely on(spoléhají se na) for reaching their seal prey(kořist). But the arctic sea ice is rapidly diminishing(mizí) due to(díky) a warming Earth.

reduced access(omezenýpřístup) to fooddrop in(pokles) body condition

lower cub survival rates(míra přežití)increase in drowning(utopení)

increase in cannibalism

The problem of global warming

Because the temperature on Earth is constantly increasing, the sea ice is melting. The polar ice-cap gets further from the land. It´s more difficult for bears to get their food, especially for mothers to that go to the land to give birth to their babies. They will need to swim back to the ice cap to hunt for their food. But it´s a very long distance. Sometimes it can be more than one hundred kilometres. Every year. Many bears die from starvation. They can die by drowning, too.

Polar bears - Patient seal hunters

Polar bears need the ice to hunt their favourite meal – seals. Seals swim in the sea and they go to the edges of ice- caps. That´s where the bears catch them. But how?A bear uses its excellent sense of smell to find holes in the ice that seals use for breathing. Then, it waits patiently to catch the seal. It can také several days but the fat from one seal is enough for one week.

Polar bears in captivity

History of polar bears in captivity. The earliest known captive polar bear was housed by Ptolemy II, king of ancient Egypt (285-246 B.C.), in his private zoo in Alexandria. Romans probably also kept polar bears.In 57 A.D., Calpurnius wrote of bears pitted against seals in a flooded amphitheater.Harold the Fair-haired of Norway received a mother and cubs in 880 A.D. from a hunter and rewarded the man with a ship filled with wood.

Polar bears in captivity

Early maps led to sources of polar bears and white falcons. Viking hunters killed mother bears and caught her cubs by attracting them to her pelt.Early rulers in Denmark, England, Germany, and Damascus kept captive polar bears.In 1874, America's first zoo opened in Philadelphia. Its bear pits were its most popular attraction.

HUNTING

Today, legal hunting continues on a limited, regulated basis for native peoples.Norway is the only polar bear nation that protects polar bears from all forms of hunting. Three of the other four nations permit native hunts—a traditionally important cultural activity and source of income. Canada is the only nation that allows sport or trophy hunting by non-natives and non-citizens.

WalkingWalking. Polar bears walk at about five to six kilometers per hour. Females with small cubs slow their speed to two and a half to four kilometers per hour.Polar bears are well known for their slow, plodding gait.

Running

Running. Polar bears can run as fast as 40 kilometers per hour—but only for short distances. Younger, leaner bears are the best runners. They can cover two kilometers without stopping. Older, larger bears quickly overheat.

Polar bears - sleeping

Sleeping. Most polar bears sleep for seven to eight hours at a stretch and they take naps, too. In that way, they're a lot like people.On the ice in spring and summer, polar bears tend to sleep more during the day than at night, probably because seals are more active at night. But day and nighthold little meaning in the Arctic where there are 24 hours of daylight in summer and 24 hours of darkness in winter.Polar bears nap just about anywhere and any time, and especially after feeding on a seal. Napping helps bears conserve energy. A polar bear's entire existence centers on hunting and conserving energy.

MaternityPolar bears sleep right through blizzards in day beds dug in the lee of a ridge. The snow piles up on top of them and provides an insulating blanket. Sometimes they stay curled up under the snow for several days until the storm passes.In summer, polar bears curl up on the tundra or on an ice patch, sometimes using a block of ice or an outstretched paw as a pillow. Landlocked bears dig sleeping pits in the sand or in gravel ridges along the shoreline.

Pregnant females dig maternity dens in snow banks in fall and give birth to cubs in early winter. Until March or April when they emerge from the den, mother and cubs spend their time sleeping.

SOURCES

• http://www.polarbearsinternational.org/about-polar-bears/global-warming#Affect

• R/R magazine – article „Mosaic“

• http://www.google.cz/imgres?imgurl=http://3.bp.blogspot.com ( picture sources)