Laurie Campbell / Mute swan (Cygnus olor) female with newly hatched cygnet, Yetholm Loch Scottish Wildlife Trust Reserve, Roxburghshire, Scotland, May

Gerrit Vyn / Spotted owl (Strix nebulosa) Gifford-Pinchot National Forest, Washington USA

Thomas Mangelsen / Spotted Owl (Strix occidentalis) in old growth forest, southwest Oregon

Gerrit Vyn / Spotted owl (Strix nebulosa) Gifford-Pinchot National Forest, Washington USA

Jenny E. Ross / Adult California spotted owl (Strix occidentalis occidentalis) perched in an ancient incense cedar tree within an old-growth section of the Tahoe National Forest, California, USA.

Jenny E. Ross / Adult California spotted owl (Strix occidentalis occidentalis) perching in incense cedar tree within old-growth forest. Tahoe National Forest, California USA. July

Floris van Breugel / Spotted Owl (Strix occidentalis) surveying the ground from its perch, at night, San Gabriel Mountains, Southern California, USA.

Kevin Schafer / Spotted Owl (Strix occidentalis) pair, northern California

Kevin Schafer / Spotted Owl (Strix occidentalis) portrait, northern California

Neil Lucas / Spotted owl {Strix occidentalis} perched, Bee Canyon, Arizona, USA

Nigel Bean / Spotted owl {Strix occidentalis} California, USA, 1993

Nigel Bean / Spotted owl {Strix occidentalis} California, USA, 1993

Nigel Bean / Spotted owl {Strix occidentalis} California, USA, 1993

John Cancalosi / Mother and young spotted owl, Mexican subspeices {Strix occidentalis lucida}, Mexico