Feathers

A gannet must keep its feathers in top condition for life at sea

Feathers are the magic material that cover the bodies of all birds and help them to fly. But they're not just for flight. Feathers are fantastic for keeping warm, which is why even flightless birds such as ostriches have them. And they have many other uses, including camouflage and display.

All change

A feather is made of lightweight material called keratin – just like our fingernails. Muscles attached to the base of each one allow the bird to move it around. Feathers have to handle a lot of wear and tear, so each year birds grow a new set to replace the old ones. This is called moulting. Some birds moult once a year; others do it twice.

Feathers up close

Each feather has a central hollow shaft, with a flat area either side – called the vane. The bare part at the base of the shaft is called the quill. A vane is made up of many small side branches, all linked together by even smaller branches with hooks, called barbules. A bird keeps its feathers tidy by ‘zipping up’ the barbules on each one with its bill. Look closely at a feather yourself; see if you can unzip it, then zip it up again.

Colour chart

The kingfisher's brilliant blue colour is created by the way the light shines off the surface of its feathers

Some feather colours, such as grey, brown, red and yellow, are made by pigments produced in birds’ bodies or in their food. A flamingo’s pink comes from the tiny plankton that it eats. Others, such as green and blue, are made by the way light shines off the surface of the feather – called refraction.

Feather care

Birds like to keep their feathers clean. They bathe regularly, and use their beak to rearrange them in the right shape and order. This is called preening. At the same time, they spread a special oil over them from a gland on their back, called the preen gland. This oil is what makes ducks and seabirds waterproof.