Roland Seitre / Blue throated / Wagler's macaw (Ara glaucogularis) chick in nestbox, Santa Cruz Zoo, Teneriffe, Canary Islands, Critically endangered species from Bolivia

Chris Gomersall / 2020VISION / Common starling (Sturnus vulgaris) adult with insect food arriving at nestbox to feed chicks, Hope Farm RSPB Reserve, Cambridgeshire, England, UK, May

Wild Wonders of Europe / Varesvuo / European Roller (Coracias garrulus) pair with intruder Roller in nestbox, Hungary May 2008

Wild Wonders of Europe / Varesvuo / European Roller (Coracias garrulus) attacking intruder Roller in nestbox, Pusztaszer, Hungary, May 2008

Wild Wonders of Europe / Varesvuo / European Roller (Coracias garrulus) pulling intruder Roller out of nestbox, Pusztaszer, Hungary, May 2008

Colin Varndell / Blue tit brings caterpillar to young in nestbox {Parus caeruleus} UK

Ann & Steve Toon / House sparrow (Passer domesticus) male feeding chick at nestbox, Northumberland, UK, August

David Woodfall / Sessile oak (Quercus petraea) nesting box sited to encourage nesting Pied flycatchers, Gilfach Nature Reserve, Radnorshire Wildlife Trust, Powys, Wales, UK May

David Woodfall / Sessile oak (Quercus petraea) nesting box sited to encourage nesting Pied flycatchers, Gilfach Nature Reserve, Radnorshire Wildlife Trust, Powys, Wales, UK May

David Woodfall / Ancient Sessile oak (Quercus petraea) with bird box, placed by Wildlife Trust for nesting Pied Flycatchers (Musciapa hypoleuca), Gilfach Nature Reserve, Radnorshire Wildlife Trust, Powys, Wales, UK Ma...

David Woodfall / Ancient Sessile oak (Quercus petraea) with bird nest box, placed by wildlife trust for nesting Pied Flycatchers (Musciapa hypoleuca), Gilfach Nature Reserve, Radnorshire Wildlife Trust, Powys, Wales,...

Charlie Summers / Tree swallow (Tachycineta bicolor) female removing fecal sac from nest, Aurora, Colorado, USA, June

Chris Gomersall / 2020VISION / RSPB research assistant surveying bird nestboxes at Hope Farm, Cambridgeshire, UK, February 2011.

Roland Seitre / Blue throated / Wagler's macaw (Ara glaucogularis) pair at nestbox, Santa Cruz Zoo, Teneriffe, Canary Islands, Critically endangered species from Bolivia

Roland Seitre / Three chicks of Blue throated / Wagler's macaw (Ara glaucogularis) in nestbox put up by conservation team, Trinidad, Beni, Bolivia, Critically endangered species, January 2008, exceptional breeding of...

Roland Seitre / Three chicks of Blue throated / Wagler's macaw (Ara glaucogularis) in nestbox put up by conservation team, Trinidad, Beni, Bolivia, Critically endangered species, January 2008, exceptional breeding of...

Roland Seitre / Chick of Blue throated / Wagler's macaw (Ara glaucogularis) in nestbox put up by conservation team, Trinidad, Beni, Bolivia, Critically endangered species, January 2008

Roland Seitre / Blue throated / Wagler's macaw (Ara glaucogularis) at nestbox put up by conservation team, Trinidad, Beni, Bolivia, Critically endangered species, January 2008

Roland Seitre / Conservation officer, Hernan Vargas Ayala, examines growing chick from nestbox of Blue throated / Wagler's macaw (Ara glaucogularis) and shows it to group of children, Trinidad, Beni, Bolivia, Critica...

Roland Seitre / Ggrowing chicks from nestbox of Blue throated / Wagler's macaw (Ara glaucogularis) Trinidad, Beni, Bolivia, Critically endangered species, January 2008.

Roland Seitre / Conservation officer, Hernan Vargas Ayala, examines growing chick from nestbox of Blue throated / Wagler's macaw (Ara glaucogularis) Trinidad, Beni, Bolivia, Critically endangered species, January 200...

Roland Seitre / Pair of Blue throated / Wagler's macaw (Ara glaucogularis) on nest box, Trinidad, Beni, Bolivia, Critically endangered species, January 2008.

Roland Seitre / Conservation officer, Hernan Vargas Ayala, examining chick from nestbox of Blue throated / Wagler's macaw (Ara glaucogularis) Trinidad, Beni, Bolivia, Critically endangered species, January 2008.

Roland Seitre / Conservation officer, Hernan Vargas Ayala, examining chick from nestbox of Blue throated / Wagler's macaw (Ara glaucogularis) Trinidad, Beni, Bolivia, Critically endangered species, January 2008.

Roland Seitre / Chick and eggs in nest of Blue throated / Wagler's macaw (Ara glaucogularis) Trinidad, Beni, Bolivia, Critically endangered species, January 2008.

Roland Seitre / Conservation officers putting up nestbox for Blue throated / Wagler's macaw (Ara glaucogularis) Trinidad, Beni, Bolivia, Critically endangered species, January 2008. Nestbox painted with initials of t...

Roland Seitre / Blue throated / Wagler's macaw (Ara glaucogularis) in nestbox, Trinidad, Beni, Bolivia, Critically endangered species, January 2008. Nestbox painted with initials of the donator who funded the conserv...

Terry Whittaker / 2020VISION / Osprey Project Information Officer, Paul Stammers, building bird boxes with children during an event at the Lyndon Visitor Centre, Rutland Water, Rutland, UK, April 2011

Ann & Steve Toon / Female House sparrow (Passer domesticus) with chick at nestbox, Northumberland, UK, June

Roger Powell / Common Gull (Larus canus) incubating on purpose built nesting platform. These "nestboxes" were originally placed to encourage gulls to nest near dwellings in order to harvest their eggs as food : but...

Roger Powell / Common Gull (Larus canus) incubating on purpose built nesting platform. These nestboxes were originally placed to encourage gulls to nest near dwellings in order to harvest their eggs as food : but th...

Stephen Dalton / Blue tit (Parus caeruleus) flying to nest box with insect prey, UK

Stephen Dalton / Blue tit {Parus caeruleus} in flight leaving nestbox, England

David Tipling / Great Tit {Parus major} chicks in nest box begging, soon ready to fledge, Norfolk April

David Tipling / Great Tit {Parus major} removing a faecal sac from nest box, Norfolk, UK

David Tipling / Great Tit {Parus major} bringing caterpillar to nest box in woodland, Norfolk, UK, April

Gary K. Smith / Blue tit (Parus caeruleus) adult birds investigating a nest box, UK, May

Dave Bevan / Pied flycatcher (Ficedula hypoleuca) female with insect prey at entrance to nest box, Wales, UK, June

Dave Bevan / Pied flycatcher (Ficedula hypoleuca) male at entrance to nest box, Wales, UK, June

Rolf Nussbaumer / Brown-crested Flycatcher {Myiarchus tyrannulus} pair at nest box, Rio Grande Valley, Texas, USA,

Rolf Nussbaumer / Juvenile Ferruginous Pygmy-Owl (Glaucidium brasilianum) in nest box, Willacy County, Rio Grande Valley, Texas, USA. June 2004

Rolf Nussbaumer / Eastern Screech-Owl (Megascops asio) with head out of Nest Box, Willacy County, Rio Grande Valley, Texas, USA. March 2004

Rolf Nussbaumer / Eastern Screech-Owl (Megascops asio) with head out of nest box, Willacy County, Rio Grande Valley, Texas, USA. March 2004

Larry Michael / Eastern bluebird {Sialia sialis} bringing insect prey to chicks in nestbox, Wisconsin, USA

DAVID TIPLING / Pied flycatcher {Ficedula hypoleuca} at nest box, Finland.

Bengt Lundberg / Common swift pair in nestbox. Male holds plant offering {Eriophorum gracile} for female 1 July. Sweden Scandinavia

Chris Gomersall / Bird friendly garden with mature trees and shrubs, nestboxes and feeders. UK