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How and Why Animals Migrate

Animals migrate for a variety of reasons. Migration is a behavioral adaptation that helps animals survive.
    Finding Their Way

Black BrantScientists aren't really sure exactly how some animals figure out how to get to where they are going. They think that some animals use landmarks like rivers and streams to find their way. Other animals may navigate by the position of the sun and stars. Scientists think some animals use smell to figure out where they are going. And there are some species that may use the Earth's magnetic field to navigate. However they do it, migration is a behavioral adaptation that has evolved over time to help animals survive.

 
    Reasons to Move
Some animals travel relatively short distances to find food or more favorable living or breeding conditions.Most animals that migrate do so to find food or more livable conditions. Some animals migrate to breed.

Atlantic SalmonThe Atlantic Salmon begins its life in a river and migrates downstream to the ocean. After several years, it heads back upstream to lay eggs and begin the cycle all over again.

Some crustaceans also migrate for breeding. In many species of crabs, the females will move into shallow coastal waters to mate and lay her eggs, then they return to deeper ocean waters.

LoggerheadFrogs and toads often move very short distances to breeding ponds and lakes to lay their eggs. Some sea turtles, like the loggerhead, return year-after-year to the same sandy beach on which they hatched to lay their eggs.

Little Brown BatSometimes animals migrate to find a place to hibernate. Little brown bats live in trees in warm months, then in cold weather they migrate to caves where it is warmer.




 


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