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When animals migrate by land, they do not have help
from the wind or ocean currents. Their journeys are often
shorter than air or ocean migrations, but the animals
sometimes have to cross deserts, mountains, or ice.
R indeer
Reindeer are a species of deer that live in the Arctic.
They are called caribou in North America. They make
longer migrations than any other land animal. Some
reindeer walk more than 4,000 kilometers every year.
Because they live in large groups, or herds, they
quickly eat up food and then they have to move to
another place.
In summer, the reindeer move north, or into the
mountains, where they can find good grass to eat.
They can feed their young here, too. They are also
safer because they can see predators like bears and
wolves, and they can escape from them more easily.
In winter, when the snow is deep, the reindeer move
to places where there is less snow, so they can find
lichens to eat. Reindeer stop growing in winter, so
they need up to 70% less food than in summer.
Altitudinal Migration
Chamois, deer, wild sheep, and
goats move up mountains in
summer because there are
fewer predators. In winter,
there is too much snow
and not enough food, so
they move down the
mountains. This is called
altitudinal migration.