Every year, certain groups of animals move from place to place. Some can travel thousands of miles in the spring and then thousands of miles in the fall. These long journeys are called migrations.
Why do Animals Migrate?
Animals migrate with changes in weather and seasons. They migrate in search of warmer weather, a better food source, or a safe place to give birth.
How do Animals know when and where to Migrate?
Various signals such as a change in weather, length of day or availability of food can signal to animals that it is time to move. Scientists aren’t sure how they know which way to go. Many people believe that animals know where to migrate when they are born. Scientists say they learn this “inherited” from their parents. This is also known as instinct.
How do they find their way?
Animals don’t have internet, GPS or even maps to find their destination, but every year they try to travel thousands of miles over land and sea. Some animals use the Sun and stars to find the right direction. Other animals use wind patterns or landmarks like mountains, rivers, and lakes. Still other animals can use an additional sense that allows them to use the Earth’s magnetic field to know direction. It’s amazing what animals can do!
Animals that Migrate
Here are some examples of animals that migrate by land, air, and sea.
Migrations on the Land
Caribou – Caribou live in the snowy tundra of the Far North. In North America, they migrate each spring to the north coast where they give birth in the summer. When autumn arrives, they migrate south below the Arctic Circle. Some herds of reindeer migrate up to 3,500 miles moving up to 35 miles a day.
Zebras and wildebeest – Every year herds of zebras and wildebeest of the African savannah migrate in a giant clockwise circle. They are constantly moving. This giant circle appears after the rainy season when food is abundant in certain areas.
Migrations in the Air
Arctic terns – The Arctic tern performs the longest migration of any animal in the world. Every six months, they travel from the North Pole to the South Pole. Then again six months later. Round trip distance is almost 50,000 miles! Fortunately, terns are strong and agile birds. They can make the trip in about 40 days.
Canadian geese – Every year, Canada geese fly south in winter to escape the cold of winter lakes and ponds. They then return north in the summer, where they breed and nest. Geese are known for their V-shape in flight. This saves them energy and allows them to fly up to 600 miles in a day.
Migrations in the Water
Gray Whale – Gray whales migrate between the cold northern waters of the Bering Sea in the summer and the warmer waters of Baja California in the winter. They give birth during the winter, then move north in early spring. They travel about 5,000 to 6,000 miles.
Salmon – Salmon have a unique return migration that they complete once in their lifetime. When they are born, they hatch from an egg in fresh water. They then grow up and eventually swim downstream and spend most of their lives in the ocean. When it comes to spawning, they return to their birthplace to lay eggs. Immediately after laying eggs, they die. Some salmon migrate hundreds of kilometers upstream. Chinook salmon swim 900 miles upstream and climb nearly 7,000 feet on their migration path.
Interesting Facts about Animal Migrations
Many animals prepare for migration by storing stored energy and even exercising certain muscles so that they are strong enough to make the journey.
The average Arctic tern will travel the equivalent of 60 times around the Earth in its lifetime.
Birds save energy and can travel long distances by riding on air currents.
Male and female walruses migrate in separate herds.
Sea turtles migrate to the very beach where they were born to lay their eggs.
Emperor penguins, excellent swimmers, travel 200 kilometers of ice each year to get to where they give birth.
Migratory flocks of European white storks can stretch up to 125 miles in length.