of silent flight

African eagle owl feather, magnified x 150. Image © Paolo Taranto

'Some of our birds fly in a way which makes them unmistakable. One of them is the Lapwing or Green Plover, whose flapping quickly identifies it. The silent flight of the owl is almost always a clue; their extremely soft feathers make them silent as they wing their way through the air. In contrast to the owls the swans beat through the air with a whistling sound you can never forget. Once you've heard a swan in flight you will always remember it.'

Spotting Birds, Jaroslav Spirhanzl Duris & Edmund Burke, Hamlyn, 1975.

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