Animal Behavior

Behavioral Ecology

Why do animals migrate?

Animals migrate for a variety of reasons, including climate (too hot or too cold during part of the year), food availability (seasonal), and breeding (some animals need a specific environment to lay eggs or give birth). Animals move between locations to take advantage of optimal environments; for example, migrating birds move twice a year, with most species flying great distances to and from their ancestral breeding grounds—most often from cold to warm areas. In the spring in the Northern Hemisphere, birds return to the north to mate, lay eggs, and raise their young; in the fall, shortening days and colder weather trigger hormonal changes that signal to the birds to return to the warmer climates in the south, where food is more plentiful.


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