Migration Why and how do animals migrate?

Migration
Why and how do animals migrate?

From Kids Discover Magazine

Most birds and other animals migrate for three basic reasons. First, animals must look for food, and maybe they may have depleted the resources in a particular area where they are. Or they may be trying to keep up with the changing patterns of available vegetation. This is what the zebras in Serengeti Forest in Africa do each year. They follow rainfall patterns in order to find ample and fresh vegetation.

Second, animals may migrate to escape extreme seasonal temperatures. For example, many birds fly south to warmer climates, for the winter, while others travel to get special seasonal shelters. Little brown bats fly 200 to 800 km from their outdoor home to their winter caves that provide a safe place for them to hibernate during the cold months.

Third, animals migrate to get to their breeding ground. Salmon, for instance, swim from the ocean to the exact area of the river where they were born. Then, they reproduce in this area before they die.

Now, in terms of how they migrate, if we are talking about day animals, they keep visual landmarks in their minds to help them move from one place to another. With the elephants, for instance, the oldest female memorizes the position of rivers, mountain ranges and other fixed spots, in order to take the members of the herd to food and fresh water. Flying animals such as birds and insects may use the position of the sun to guide them as a compass. If they are night animals, their specialized nocturnal vision allows them to see the shades of the trees in the dark. But to migrate at night in the forest, night animals’ preferred method is by guiding themselves by observing the position of the stars, just like exploring navigators used to do in the XV century.

Available at: <http://www.kidsdiscover.com/blog/spotlight/animalmigrations- for-kids/> Retrieved on: nov. 20, 2012. Adapted.

In the text, the third reason given for an animal to migrate is to