Polar bears are ancestor of the brown bear and appeared 200 000years ago. Theses bears are highly adaptive to northern latitiudes.Five nations have polar bear populations: the United States (Alaska), Canada, Russia, Denmark (Greenland), and Norway.
Male weight-775 to 1500 pounds
Female wight 330 to 550 pounds
Number of cubs born 1-3 average 2 at a time
Parental care (stay with mother) 2 to 2and a half years "In zoos, polar bears have been known to turn green due to colonies of algae growing in their hollow hair shafts. This happened at the San Diego Zoo in 1979. No harm came to the bears, and zoo veterinarian Phillip Robinson restored the bears to white by killing the algae with a salt solution." from http://www.polarbearsinternational.org/
Polar bears are the top predator in Artic climates.They hunt seals and wait patiently at water holes for an seal to appear. So the top food sources of the polar bear are:
- Ringed seals
- thick layer of blubber
- 4.1 feet long and 150 pounds
- get stuck in ice easier target for polar bears
- "Alaskan marine biologist Lloyd Lowrey observed a group of bears capture about 40 whales at a savsatt in the northern Bering Sea. And in 1999, 13 bears harvested beluga whales trapped in a savsatt near Canada's Ellesmere Island." from http://www.polarbearsinternational.org/
Polar bears use a combination of body language and 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 that 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.
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.
Attacking polar bears charge forward with heads down and ears laid back.
Submissive polar bears always move downwind of dominant bears.
Endangered
"As of May 2008 the U.S has listed the polar bear as a threatened species under the Endangered Species Act. In Canada, polar bears are listed as a species of special concern. Russia also considers the polar bear a species of concern."
Why?
-global warming which is changing the environment and food sources and hunting habitia for the polar bear.
(2) Artic Wolves
-subspecies of the gray wolf
- lives alone or in packs of about 6 wolves
- lives about 10-15 years in the wild; it lives about 20 years in captivity.
Anatomy
- Arctic wolves are usually smaller than gray wolves, and also have smaller ears, slightly shorter muzzles, and shorter legs to reduce exposure to the frigid air
- Height: To shoulder, 25-31 inches.
- Length: Head and body, 3-5 feet.
- Weight: Up to 175 lb. Female, lighter.
Diet
- Musk oxen, Peary caribou, Arctic foxes, ptarmigan, lemmings, seals, nesting birds, and Arctic hares
**They mostly eat caribou, and they kill their prey with a devastating bite on the neck.
Threats
- Polar bears, other wolves, humans
Breeding
Sexual maturity: Males 3 years. Females 2 years.
Gestation: 61-53 days.
Number of young: Usually 4-5.
(3) Artic Fox
Diet: Omnivore
Average life span in the wild: 3 to 6 years
Size: Head and body, 18 to 26.75 in (46 to 68 cm); tail, up to 13.75 in (35 cm)
Weight: 6.5 to 17 lbs (3 to 8 kg)
Group name: Skulk or leash
Size relative to a 6-ft (2-m) man:
- TheArtic foxes white fur is a mechanism for the fox to hunt effective for prey but also hide from predators in the winter season and then turn into a brown gray hue to blend in the summer environment.
- The artic fox hunts rodents, birds, and even fish. But in winter prey can be scarce on the ground. At such times, arctic foxes will follow the region's premier predator—a polar bear—to eat the leftover scraps from its kills. Foxes will also eat vegetables when they are available.
- Female arctic foxes give birth each spring to a large litter of up to 14 pups.
Diet: Herbivore
Average life span in the wild: 15 years
Size: 4 to 5 ft (1.2 to 1.5 m) at the shoulder
Weight: 240 to 700 lbs (109 to 318 kg)
Group name: Herd
Protection status: Endangered
- Also called reindeer
- Found in North America, Europe, Asia and Greenleand
- In the summer months the herd moves north and travel 600 miles
- Feed on glasses and plants and eat around 12 pounds of food a day.
- During migration, herds of cows (female caribou) leave several weeks before the males, who follow with yearling calves from the previous birthing season.
- Hooves are specialized for the tundara environment used for digging in snow for food and the sharp edges on hooves good for walking on ice and rock.
- Caribou are the only deer in which male and females both have antlers—though only some females have them.
- When winter comes the caribou moves southward.
- Size: 22-28 in.
- Weight: 9-12 lb.
- Color: Brown in the summer, white in the winter. Ears tipped with black year round.
- Distinguishing Characteristics: Short ears, and a fur coat that changes color with the seasons make the arctic and tundra hare special.
- Breeding: Leverets born June thru July. Usually there are 4-8 in a litter. They are fully furred and have their eyes open.
- Found in Canada and Greenland in forested or low land areas and live in groups for projection.The fur colour is a mechanism to hide from predators.
- Their diet includes willow,leaves, shoots, bark and roots - and grasses, flowers, saxifrage and crowberry.
- "The major difference between a rabbit and a hare is that the young of a hare are born open-eyed and furred. The rabbit's young are born naked and with closed eyes. Hare are able to leave the nest soon after they are born but rabbits don't even open their eyes for 7-10 days" from http://library.thinkquest.org/3500/arctic_hare.html
- They sport thick fur and enjoy a low surface area to volume ratio that conserves body heat, most evident in their shortened ears
- Arctic hares are fast and can bound at speeds of up to 40 miles (60 kilometers) an hour
(6) Musk Ok
Diet: Herbivore
Average life span in the wild: 12 to 20 years
Size: Height at shoulder, 4 to 5 ft (1.2 to 1.5 m)
Weight: 500 to 800 lbs (227 to 363 kg)
Group name: Herd
- Musk-oxen eat roots, mosses, and lichens they use their hooves to dig through snow to graze on these plants and in the summer they eat grasses and flowers
- The musk-oxen is well adapted to the artic environment and has live in the cold region for thousands of years.
- The outer hairs, called guard hairs, cover a second, shorter undercoat that provides additional insulation in winter.
- Female musk-oxen carry their calves during an eight-month pregnancy, but after birth there is little time to waste. The infants are able to keep up with their mothers and the rest of the herd within a few hours.
- Herds use cooperation to deal with predation by wolves or dogs. When threatened, they "circle the wagons" and array themselves with their young in the middle and their sharp horns facing outward toward their foes. A cornered musk-ox can be a fearsome enemy, charging with its massive bulk and attempting to use its horns to deadly effect.
- Such defenses are not terribly effective against human hunters, who killed great numbers of musk-oxen for their hides and meat. Today, legislation protects herds in Alaska, Norway, and Siberia, where the animals live on preserves.
No comments:
Post a Comment