In the early days of racing, paint was used to identify birds for owners.

I like ducks partly because I can't identify little birds.

He can also identify birds by the speed and rhythm of their wingbeats.

At a young age he learned to identify most animals and birds by their calls - owing to his frequent excursions.

He was teaching himself how to identify African birds.

Park workers from around the country are being trained to identify infected birds.

After the workshop, I could identify maybe a half-dozen other birds.

But serious birders tend to identify most birds through sound, which is faster and easier, especially at night.

We could identify birds by either seeing them or by their songs.

Two new threats have been identified since 2000: alien birds and ectoparasites.