Arctic foxes are able to travel distances similar to the width of Canada, from the Pacific to the Atlantic in a matter of months, scientists report. A research team tracked the small animals over the course of a year.
One female fox covered a distance of 4,600km in 5.5 months. The species was also found to travel an average of 90km/day for several days. Tracks in the snow can be used to work out the abundance of the animals.
The study has shown that Arctic foxes are able to navigate over hundreds of kilometres. They can leave their den in winter, travel 600km away and return to the very same den the following summer.
Researchers working on Bylot Island, an Arctic island that is part of Canada's Sirmilik national park, fited foxes with satellite transmitters that tracked the animals for up to a year.
The team, from the University of Quebec at Rimouski, Canada, found that foxes spent a lot of time on sea ice during winter. Diminishing sea ice linked to climate change may have dramatic consequences for the animals.
The foxes moult twice a year, having the colour of snow in winter and of tundra in summer. A rare "blue" morph with dark fur occurs in Iceland and Greenland. Their winter coat more insulating than the coats of polar bears.
The researchers work in the challenging Arctic environment for periods of three to four months in summer. They set up fly camps, enabling them to study fox dens scattered throughout the large research area.
In order to reach the Arctic island of Bylot (73°N, 80°W) with all the equipment, researchers use a small twin-otter plane. The aircraft can land almost anywhere, such as this frozen lake next to the main research camp.
The team capture Arctic foxes using cages or padded foot-traps. After anaesthetising the animals, the scientists take blood, hair, and claw samples. Why the foxes go on these long trips and how they navigate is still unclear.
Red foxes, through a northward expansion of their range, represent a potential threat to Arctic foxes. Although the creatures are very rare on Bylot Island, researchers have found some red foxes.
Using infrared-triggered automatic cameras, the team captured these red fox cubs playing on their den. How red foxes fare in this environment could have a significant impact on the future of the Arctic fox.
Arctic foxes are very opportunistic and can eat many different types of food. They especially like to prey on lemmings. This adult arctic fox brings back at least two lemmings to the cubs waiting inside the den.
It is difficult for the team to work out the exact age of the foxes, but tooth wear can give an indication. "They don’t always show their teeth so easily as this one," says Arnaud Tarroux who undertook the study.
What are these?
E-mail this to a friend
Bookmark with:
What are these?