In spring, many bird species fly north as they return to their breeding grounds. This migration is driven by the availability of food and suitable nesting habitats that emerge as temperatures warm. Conversely, in the fall, these same birds typically migrate south to escape colder weather.
Migratory birds fly south during autumn and return north in spring.
They fly.
Cause in the North it can get really cold and birds don't mostly survive in the cold so they fly south were it's warmer or hotter.
humming birds migrate the same way the other birds do. Like when it is cold in north they fly south and when it is cold in the south they fly north.
When birds fly south for winter each year, this is known as "migration." The birds fly south to live in a warmer climate, and in the spring they fly north again when the weather changes.
Birds Fly South was created in 2001.
When the Birds Fly South was created in 1945.
When the Birds Fly South has 223 pages.
Swallows.
They would freeze to death
Many birds migrate to warmer climates in the winter to find food and escape the cold weather. They may travel thousands of miles to reach their wintering grounds, where they can find resources to survive until it is time to return to their breeding grounds in the spring.
Birds do not fly all the way to the southern hemisphere, they fly to the equator.