Donald M. Jones / Northern Pintail (Anas acuta) males flying with female in spring courtship display, Montana

Donald M. Jones / Northern Pintail (Anas acuta) drake flying, central Montana

Donald M. Jones / Northern Pintail (Anas acuta) flock flying, North America

Mark Carwardine / Adult male Northern pintail duck (Anas acuta) flying, Bosque del Apache National Wildlife Refuge, New Mexico, USA

David Kjaer / Pair of Northern pintail ducks (Anas acuta) in flight, Gloucestershire, England

Alan Williams / Pintail (Anas acuta) male flapping wings after bathing, Martin Mere WWT reserve, Lancashire, UK, February

Mike Potts / Pintail ducks (Anas acuta), Four males courting one female, Martin Mere, Lancashire, UK February

Jack Dykinga / Pintail duck (Anas acuta) on waves during winter storm, Bosque del Apache National Wildlife Refuge, New Mexico, USA, January.

Jack Dykinga / Pintail ducks (Anas acuta) in the marshes at dawn, Whitewater Draw, Arizona, USA, January.

Donald M. Jones / Northern Pintail (Anas acuta) drake flying, Montana

Donald M. Jones / Northern Pintail (Anas acuta) males flying with female in spring courtship display, Montana

Donald M. Jones / Northern Pintail (Anas acuta) males flying with female in spring courtship display, Montana