Migration is a form of adaptation. Birds migrate to survive. Learning about migration is one of the best ways to understand the risks that birds and other animals must take in their daily lives - and it's a great way to interpret the changes you can see in the bird life around you.
A look at bird migrations
Which birds migrate?
Not all birds migrate, such as partridges. But they are in the minority - most birds will migrate.
Getting ready to go
A bird's body tells it exactly when to migrate. Each year, glands in its body release hormones into its system.
Choosing the route
Migrating birds don't just point themselves in the right direction and hope for the best. Each species has its own route
Dangers of migration
Migration is a gamble. Birds have to deal with all kinds of dangers on the way.
It's only in the last 100 years that we've begun to understand migration. Before then, people had some strange ideas.
Through the oceans
It's not just birds that migrate - some deep ocean fish migrate daily! We take a look at underwater migration stories.
Migratory bird stories
Arctic terns have the longest migration of all. This means a round trip of up to 35,000 km each year.
Satellite tags have told us a lot about osprey migration.
Swifts need warm weather to provide a constant supply of flying insects, so they spend only about three months in the UK each year.
Other migratory animals
It's not only birds that migrate. Animals of all shapes and sizes - from butterflies and eels to turtles and reindeer - are also on the move every year.
A history of migrating herds
Huge herds of migrating animals are an amazing sight.
Why do people migrate?
Humans are also animals, and - like most animals - we migrate.
Mole, vole and toad migration
Every spring, common toads make the short but risky trip from the woods where they spend winter to the ponds where they breed.
How are we doing?
We've been making changes and we'd love to know what you think.