Bernard Castelein / Darter ( Anhinga melanogaster) drying wings, Keoladeo NP, Bharatpur, India

Tui De Roy / Flightless cormorant (Phalacrocorax harrisi), two on rock. Bird drying wings in foreground with other sitting on nest in background. Cape Douglas, Fernandina Island, Galapagos.

Tui De Roy / Flightless cormorant (Phalacrocorax harrisi), Punta Espinosa, Fernandina Island, Galapagos

Bence Mate / Pygmy cormorants (Phalacrocorax pygmaeus) drying their feathers, Hortobay, hungary, August.

Richard Steel / 2020VISION / Female Goosander (Mergus merganser) drying feathers, Gwynedd, Wales, UK, January.

Nick Garbutt / Male Comet / Madagascar moon moth (Argema mittrei) recently emerged drying its wings. Andasibe-Mantadia National Park, Madagascar.

Wild Wonders of Europe / Radisics / Rear view of two Pygmy cormorants (Microcarbo pygmeus) perched on branch drying wings, Hortobagy National Park, Hungary, July 2009

Wild Wonders of Europe / Radisics / Rear view of Two Pygmy cormorants (Microcarbo pygmeus) perched on a branch, one with wings stretched out drying, Hortobagy National Park, Hungary, July 2009

Bernard Castelein / Cinereous / European black vulture (Aegypius monachus) spreading wings on ground, Rajasthan, India

Graham Eaton / Rear view of Gadwall (Anas strepera) drying its wings, London Wetland Centre, UK, August

Andrew Parkinson / Canada goose (Branta canadensis) drying its wings after bathing, Derbyshire, UK

Tim Fitzharris / Double-crested Cormorant (Phalacrocorax auritus) drying its wings, North America