The Arctic Tundra
Learn about the worlds most inhospitable habitats – the Arctic Tundra. Yet despite its harsh weather condtions, the tundra supports a wide range of wildlife.
- The Arctic Tundra
- ANIMALS OF THE TUNDRA - MAMMALS
- ANIMALS OF THE TUNDRA - BIRDS
- ANIMALS OF THE TUNDRA - FISH & INVERTEBRATES
The Arctic Tundra
The Tundra is an area that surrounds the North Pole. It spans from the North Pole to the northern latitudes of Europe, Asia and North America, and the larger islands of the Arctic Ocean. It is a snow-coverered desolate land for most of the year. During the brief summer, however, the cold weather subsides, allowing the wildlife to come to life. When the winter snow does melt for its brief moment, the tundra landscape becomes a boggy and wet - then reveals what the ice has accomplished from under the snow.
Below the surface of the Tundra lies a Permafrost - this is a forever-frozen soil approximately 1 km thick!
The Tundra stretches a vast distance of about 7000 km from Norway to the Bering Sea and covering a 2.6 million square km arc of North America. As an ecological imaginary boundery, the Tundra's northern fringe defines the limit of nearly all plant life while its southern border marks the northern limit at which trees can grow.
An interesting feature about the Tundra landscape is the fact that there are many 'pingos'. Pingos are low domes or mounds up to 300m across that are formed by underground water expanding and bulging upward at is freezes.
Scandinavian folk, the Saami people, have for many years herded reindeer on the tundra. Pollution from the Chernobyl nuclear meltdown in 1986 has led to high levels of radioactivity in these animals.
The word 'Tundra' comes from the Finnish for 'treeless plain'. The whole area is a vast emptyness of snow in the winter. Along with the harsh weather, poor drainage as well as meagre rainfall limit plant life to grow. But nevertheless, certain species thrive. As well as mosses, lichens and hardy grasses and sedges, there are more than 500 species of wildflowers.
ANIMALS OF THE TUNDRA - MAMMALS
Mammals are abundant in the Tundra despite the fierce winters. Caribou, otherwise called reindeer, migrate northward over the tundra during the summer months to help themselves to the fresh vegetation. Other large herbivores include the moose and musk oxen.
Musk oxen are particularly well guarded against the Tundras extreme weathers. It has a dense undercoat that allows no water or cold to penetrate, and an outercoat of long, course hair that almost touches the ground to protect it from snow and rain. When musk oxen become threatened, they form a circle facing outward with their horns lowered. This protects the young that are kept safe in the center of the circle. This stance is particularly effective with wolves which are the main predator of the musk oxen.
The tundra also inhibits brown bears and polar bears which also help themselves to the wildlife of the Arctic Tundra. But it is the wolf that wins the census of the most widespread predator. Wolves hunt in packs, especially when stalking large prey and seeking out young or injured animals from musk ox and caribou herds.
The smaller range of tundra mammels comes from the burrowing sort: voles, ground squirrels, lemmings and weasels. These animals make up the main diet of smaller tundra predators such as the Arctic Fox.
ANIMALS OF THE TUNDRA - BIRDS
The tundras summer months brings with it a vast majority of birds. The swarms of hatching flies create an abundant food supply for the breeding birds and their newly hatched young. Other birds supplement their insect diet with berries and buds.
Plovers are a typical bird species that spends its time breeding in the brief summer of the tundra. Although some species can breed in the extreme northern latitudes because both parents play a part in feeding the young.
Not all birds come, breed and go. There are some bird species that reside in the tundra all year round. These include the snowy owls, eider ducks and ravens. One of the most destinctive is the ptarmigan, which spends the winter in snow tunnels that are reputed to be 35 degrees Celcius warmer that the night air. The ptarmigan is usually unable to find much food when it emerges during the winter months, so it lives mainly off a layer of fat that it builds up during the summer when it gorges on snakeweed bulbs and other protein-rich plant matter. The ptarmigan moults into almost pure-white camouflage plumage for the winter months on the snow-covered tundra.
ANIMALS OF THE TUNDRA - FISH & INVERTEBRATES
The most common and significant insect on the tundra is the mosquito. They survive by sucking the blood of the wide variety of animals that graze here during the summer. During the thaw pools of meltwater cover the landscape making the perfect breeding ground for insect larvae. The larvae are eaten by Arctic char and other fish, which also take adults that fly low over the water.
Lakes and rivers are also the home of salmon, lake trout, grayling and tom-cod.
On insect in particular that is active throuhgout the tundra year is the busy little bumble-bee. These insects are well equipped to be out in the harsh weather which is too cold for other insects. It is most likely that the bumble-bee's compact and hairy body enables it to conserve the heat that it generates by its rapid wingbeats.