Thursday, January 7, 2010

Alan & Fleck have an "Arctic Fox" of a time

There are two particular residents of Kent who have been enjoying the cold snowy conditions more than anyone else.

Wildwoods resident Arctic foxes have been feeling right at home as snow blankets their enclosure making them truly feel they are in the arctic.

During the rest of the year Alan and his daughter Fleck find modern Britain a bit on the warm side but in the winter they really perk up.

Arctic foxes are natives of the cold arctic regions of Northern Europe and can cope with temperatures as low as -50 degrees Celsius. Once a British species they became extinct in the UK after the last ice age - mainly killed by man for food and fur.

Arctic Foxes are just one of the huge range of British animals that can be seen at the Wildwood Discovery Park, for more information visit the website at http://www.wildwoodtrust.org/ or telephone 0871 7820087.

Wildwood is an ideal day out for all the family where you can come 'nose to nose' with British Wildlife. Wildwood offers its members and visitors a truly inspirational way to learn about the natural history of Britain by actually seeing the wildlife that once lived here, like the wolf, beaver, red squirrel, wild boar and many more.

Wildwood is situated close to Canterbury, just off the A291 between Herne Bay and Canterbury. For more information visit our website at http://www.wildwoodtrust.org/ or telephone 0871 782008.
Arctic Fox Facts
  • Arctic fox a member of the order Carnivora and is one of 14 fox species in the dog family, the Canidae.


  • Foxes, unlike wolves, share many traits with cats – highly sensitive whiskers on their muzzles and wrists, lighter, more agile bodies, partially retractable claws, they stalk and pounce and have soft toe pads and hair between their toes (thought to be adaptations for sneaking up on rodents), and pointier cat-like canines for efficient killing.


  • One suggestion for these adaptations is that Nature came up with common solutions to common problems; another is that the fox’s cat-like features were inherited from an ancient ancestor that lived before the cat-dog split.


  • Intelligent and adaptable, brazen and curious.


  • It will defend its food against a marauding wolf, explore the deck of an icebound ship and stick its nose in an explorer’s tent.


  • Generally a solitary predator, hunting and feeding alone, unlike its more sociable cousins, the wolf and the dog; largely nocturnal.


  • The Sami people of northern Scandanavia call it svale – the bold one.


  • Its range is circumpolar, everywhere north of the Arctic Circle – US northern tundra, Canada from the Yukon to Hudson Bay, Labrador and Baffin Island, Norway, Sweden, Finland and northern Russia, plus almost all Arctic islands and the polar ice cap (explorers have found Arctic fox tracks within a few miles of the North Pole itself).


  • Some foxes stay in the same area throughout their lives; others undertake epic journeys of thousands of miles.


  • Population estimates vary between 300,000-1 million worldwide, but the number is considered irrelevant because populations reproduce and die in dramatic waves (boom and bust). The important consideration is that the species survives successfully on such an extreme environment.
Adaptation
  • Almost every aspect of Arctic fox physiology is finely tuned to conserve heat energy.


  • The Arctic fox breaks some of the key rules of biology: 1) that larger animals have an easier time in cold conditions because a large body has a smaller surface area, relative to its body mass (i.e. heat doesn’t leave a bulky mass as fast as it does a small one) and 2) Allen’s Rule - after zoologist Joel Allen – which states that warm-blooded animals living in cold environments tend to have shorter limbs and more compact bodies.


  • The Arctic fox is tiny and combines long legs and a slender body with a flatter face and shorter ears.


  • Its circulation is designed to conserve heat loss. The arteries and veins in the animal’s extremities are very close together, transferring heat energy from the outgoing warmed arterial blood to the incoming veins, before it can be lost in the outer extremities. So the blood in the feet and extremities is a lot cooler and the warm blood is kept circulating in the core areas of the head and torso, conserving heat. Rather than heat the whole house, the Arctic fox closes the door on those areas than can withstand a lower blood temperature. Caribou/reindeer do the same.


  • It can also shrink the blood vessels leading to its skin to control heat loss.

    This means its paws in particular can be maintained at just above the point at which they would succumb to frostbite, well below the animal’s core body temperature.


  • Why is this cold tolerance so amazing?

    Scientists regard the Arctic fox’s cold tolerance with awe, especially as instead of using shelter as they are usually out in the open, curled in a ball, against the worst Arctic blizzards.

    The fox is dealing with the following problems:

    • a difference in temperature between its blood and the air around it of perhaps 100ÂșC


    • a barren Arctic environment with little food


    • no behaviour changes to cope with the cold – it doesn’t hibernate, migrate or socialise to huddle together and conserve heat


    • its size is tiny – it’s the smallest tundra animal living out in the open in winter (an adult Arctic fox weighs just 3.5Kg, compared with an Arctic hare which weighs 50% more).
  • Scientists say the Arctic fox is pushing animal life as far as it can go.


  • Many of the other Arctic species are considered cheaters – they have evolved to avoid the cold rather than endure it. Many bird species migrate south to avoid the worst of the Arctic winter and small mammals like lemmings survive by spending the entire winter in a relatively warm network of tunnels under the snow.

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