Animal Migration

Many mammals, birds, fish, insects and other animals travel regularly from one place to another during a certain time of the year. This journey is called migration. Animals change their living areas because they may get more food, better places to build nests or more sunlight somewhere else.

Some animals travel thousands of kilometers across land and water. Others travel only short distances. Water animals, for example, often move vertically from deeper water to the surface area.

Birds

Birds are animals that travel the greatest distances. Many types of birds migrate each year between their breeding grounds in the northern part of the world and warmer regions near the equator where they spend their summer months. In tropical regions birds often travel from wet to dry areas.

The Arctic tern spends the summer in the Arctic regions and then flies half way around the world to the Antarctic for the winter. When flying, most birds follow geographical features, like mountains, rivers or islands.

A few types of butterflies are also long-distance travelers. The monarch butterfly, for instance, spends most of the winter in Mexico and then travels back to the United States in the spring.

Mammals

Mammals do not migrate so much because walking is slow and takes up too much time. There are, however, hoofed animals that do travel longer distances in order to search for better grazing places.

Reindeer or caribou can move long distances between their winter and summer homes. They migrate in herds of up to 100,000 animals. Caribou spend the summer in the Canadian Arctic and then travel up to one thousand kilometers to the forests along the American border.

Zebras and other wild animals that live in the Serengeti area migrate every year in search of new pastures and food. During annualrainfall they spread out and during the dry season they gather together around waterholes.

Some sea mammals also migrate. Whales travel from colder Polar Regions to warmer water where they mate and bring up their babies. Then they travel back to the colder waters, where there is more food. Seals often do the same.

Wildbeest during great migration

Reptiles

Although most reptiles do not migrate so much there are some that follow a yearly cycles. Sea turtles spend most of their life at sea but each year they come to the coasts and lay their eggs in nests on the beach. The most famous breedingplace is Ascension Island in the middle of the Atlantic Ocean. Turtles come from the coast of Brazil over a distance of 2000 km and make their nests there.

Fish

The best known migratory fish is the salmon. It is born in freshwater rivers and then swims to sea. There it finds a lot of food an grows very quickly Salmon can spend one to three years in ocean waters and then swim back to the rivers where they hatched to lay their own eggs. Most of them find their way back home because of the smell of the water in which they were born.

How animals navigate

Scientists do not completely know how animals find their way. Birds use the sun and the stars to find the right direction. Some animals are guided by temperature, wind direction or ocean currents. Others use the earth’s magnetic field to navigate.

Words

• although =while
• annual = yearly
• breeding ground = place where animals go to in order to have babies
• caribou = a North American reindeer
• coast = place where the sea meets land
• cycle =the same events that happen again and again
• direction =the way or route something goes or points to
• distance =how far two things are from each other
• equator = a line around the middle of the earth
• feature = mark, characteristic
• follow = to go after
• for instance = for example
• freshwater = water that has no salt ; opposite of sea water
• gather = get together
• graze = an animal eats grass that is growing
• guide = to show the way
• hatch = if a young animal comes out of an egg
• herd = a group of animals that live together
• hoof = the hard foot of an animal, like a cow or horse
• long distance =a long way to travel
• mammal = animal that drinks milk from its mother’s body when it is young
• mate = animals gat together to have babies
• migrate = to travel from one place of the world to another
• migration = when animals travel from one part of the world to another
• navigate = here: travel
• ocean current = the movement of water in the sea
• pasture = land that is covered with grass and used for animals to feed
• regularly = very often, at the same time each year
• reindeer = a large deer with long, wide antlers ;it lives in colder areas
• reptile = type of animal whose body temperature changes according to the temperature around it; it usually lays eggs to have babies
• salmon = large fish with silver skin, that lives in the sea but swims up rivers to lay eggs
• seal = a large animal that eats fish and lives near the coast
• smell = to put your nose near something to find out how it smells
• spread out = to move over a larger area
• surface =the top layer of an object
• tern = a black and white sea bird that has long wings and a tail with two points
• vertical = up an down
• waterhole = a small area of water in a dry country where wild animals drink
• whale = a very large animal that lives in the sea and looks like a fish, but is a mammal