Caribou, Deer, Elk & Moose - Sounds Wild
Caribou Craters

Audio

Download Episode: Caribou Craters (MP3 file 2,398 kB)

Transcript

On a winter day, wildlife biologists are flying over the snow-covered tundra of Southwest Alaska. They’re studying caribou nutrition, and they’re following a long trail of caribou tracks in the snow – a large group walking single file. Suddenly the tracks begin to spread out and there they are, about 300 caribou foraging on lichens, pawing through the snow to reach the ground. Each caribou has created a crater in the snow. The area is pockmarked with craters, hundreds of moonlike craters exposing the brown tundra beneath the snow.

The caribou are targeting lichens. There’s a particular lichen that is especially nutritious, it’s known as caribou lichen, sometimes called reindeer moss, although it’s not moss at all, it’s lichen. Moss has almost no nutritional value, and lichen is a good food for caribou. The caribou lichen is highly digestible and has a high energy content. While it’s generally thought that animals like moose and caribou put on weight in summer to help them survive the winter. While that’s generally true in many cases, Researchers have found that caribou are actually able to gain weight in winter, adding both body fat and muscle mass.