Tern

Terns are generally white in colour with shades of grey

These graceful birds fly above the water, searching for dinner. When a tern spots a fish, it swoops down under the water and comes up with a fish in its mouth.

If birds could earn frequent flyer miles, terns would definitely earn the most. Almost all terns migrate, and the Arctic tern migrates every year from the Arctic to the Antarctica –a 40,000km trip, one way

Common tern colonies usually number around 2,000 birds, but can be as large as 20,000. They are often shared with other tern species such as Arctic and roseate terns.

You can probably imagine that, with so many nests in one colony, it must be difficult for the terns to remember exactly where their own nest is. However, studies have shown that common terns can find their eggs even if they have been buried and no evidence of the nest remains. This is a necessary adaptation in such an exposed environment where losing a nest is likely.

Common terns which live by the coast have nasal glands (as have many seabirds) that enable them to drink salt water by excreting the excess salt, and they do not drink fresh water even if it is available.

A Common tern when incubating flies off the nest in order to defecate at a distance of 5-50 m (16-160 ft), doing so in water nearby or on the territory of another tern.