Why Do Caribou Migrate In Winter

Ptarmigan geese and terns all migrate to the arctic in the spring to nest.

Why do caribou migrate in winter. Their summer range provides nutritious food that helps the new calves and the other caribou grow healthy and fat before winter. In the wild most caribou migrate in large herds between their birthing habitat and their winter habitat. The circulation through the legs is up to 50 degrees colder than the circulation system for the rest of their body. Some mammals like whales bats elk and caribou also migrate to warmer locations each winter.

The last remaining european herds of the genetic wild reindeer are found in central norway. But the summer range is a harsh and windy place during winter so the caribou move to a winter range where conditions weather food snow cover are more agreeable. The boreal forests offer favorable snow conditions that allow the caribou ready access to their favorite winter food source lichens of which they need to eat approximately 3 kilograms each day. They cannot stay in one place without using up the available food supplies or losing them to winter weather.

Caribou have 2 circulation systems in their bodies. The herds spend the winter in more sheltered climes and survive by feeding on lichens. Many species of fish such as salmon also follow yearly migration patterns. When a caribous antler is broken between april and august when in the velvet stage it loses blood flow to the antler and velvet.

The other members of the herd follow the females one or two weeks later. They move north in the spring and south in the fall. Arctic caribou migration this grand migration is embarked upon by the caribou to find food and lay on fat for the rutting period and the winter. Caribou are taller and lankier than reindeer likely because they evolved to make these long migrations.

The spring melt of arctic snow triggers pregnant females to begin the annual caribou migration to calving grounds where the herd will pause briefly while calves are born. Caribou migrate to find food. Whales travel south to spend winter there but there isnt as much food as there is up north.