Showing posts with label nature. Show all posts
Showing posts with label nature. Show all posts

Thursday, 20 September 2007

Polar Bears Hunt Belugas

Feeling a little uninspired today, I hope you don't mind a repost from March on an amazing topic that few people believe until they see the footage (the most popular source is David Attenborough's Planet Earth).

Polar bears live a feast and famine lifestyle. They are large animals (an adult males weighs 300-600kg) that live in the freezing tundra so they have huge metabolic needs. They normally prey on ringed seals but will eat almost anything they can catch, including walruses, birds, eggs and occasionally they supplement their diet with a big, juicy, beluga whale!

Beluga whales are distinctive for their pale skin and large melon shaped head. These animals can grow up to 5m (16ft) in length and live in large pods, mainly in the Arctic and Canadian Subarctic. Belugas live close to coastlines and in winter they occasionally become trapped in savsatts, small openings in ice packs. Belugas can find themselves the victims of shrinking savsatts, which they use to breath. Each animal will take a turn coming up for air and in the worst of winter, their movement is all that keeps the savsatt open.

Hence an opportunity that a wandering polar bear may chance by and certainly one he can’t resist. The bear will jump in the water, clubbing the trapped whale with his paw and gorging it with his claws. It may take several attempts but the bear usually succeeds in his catch and drags the whale’s carcass on to the ice for a feast. Other polar bears will share in the prize and any leftover kill will be happily devoured by scavenging arctic foxes and gulls.

If you find this post interesting I encourage you to also check out Darren Naish’s very cool post on Wolf-Hunting Eagles

More information can be found at Polar Bears International.

Tuesday, 1 May 2007

Lonesome George isn’t alone anymore

Lonesome George, the giant Galapagos tortoise that has become a conservation icon may not be the last of his kind after all. George was thought to be the only survivor of a Geochelone abingdoni, a species of tortoise native to the Pinta isle.

But this week, Current Biology has reported a hybrid of the Pinta tortoise and another species discovered on Isabela isle. So the new tortoise, though not completely like George, is proof that hybrids are possible and the future of the George’s species doesn’t look as bleak anymore.

The new turtle is male so can not mate with George, who seems happy as a hermit. George has snubbed the many opportunities he has been given to mate with female tortoises of closely related species.

Researchers hope that a more thorough sampling of the 2,000 tortoises living on the island could reveal another of Georg’s species but are cautious as the project may be expensive and time-consuming.

It is thought that the collapse of the giant tortoise population on Pinta is due in large part to whaling activities in the Pacific during the 18th and 19th Centuries when sailors would take tortoises to store as food on their ships. They pefered the females, which were smaller and easier targets in lowland areas during the egg-laying season. By the middle of the 20th Century, only one giant tortoise was left on Pinta: George who is thought to have been born in the 1920s.

Monday, 26 March 2007

Bears Hunt Belugas

This is my third polar bear post in a month, after posting about polar bear/grizzly hybrids and the orphaned polar bear cub, Knut I hope you’re not getting tired of them, they are fascinating creatures.

Polar bears live a feast and famine lifestyle. They are large animals (an adult males weighs 300-600kg) that live in the freezing tundra so they have huge metabolic needs. They normally prey on ringed seals but will eat almost anything they can catch, including walruses, birds, eggs and occasionally they supplement their diet with a big, juicy, beluga whale!

Beluga whales are distinctive for their pale skin and large melon shaped head. These animals can grow up to 5m (16ft) in length and live in large pods, mainly in the Arctic and Canadian Subarctic. Belugas live close to coastlines and in winter they occasionally become trapped in savsatts, small openings in ice packs. Belugas can find themselves the victims of shrinking savsatts, which they use to breath. Each animal will take a turn coming up for air and in the worst of winter, their movement is all that keeps the savsatt open.

Hence an opportunity that a wandering polar bear may chance by and certainly one he can’t resist. The bear will jump in the water, clubbing the trapped whale with his paw and gorging it with his claws. It may take several attempts but the bear usually succeeds in his catch and drags the whale’s carcass on to the ice for a feast. Other polar bears will share in the prize and any leftover kill will be happily devoured by scavenging arctic foxes and gulls.

If you find this post interesting I encourage you to also check out Darren Naish’s very cool post on Wolf-Hunting Eagles!

More information can be found at Polar Bears International.