Pedro Narra / Barn Swallow (Hirundo rustica) in flight. Portugal, Europe

Dave Bevan / Pair of Sand martins (Riparia riparia) feeding chicks, Carmarthenshire, Wales, UK, July.

Murray Cooper / Swallow-tailed Nightjar (Uropsalis segmentata) female in defensive posture on nest, South America

Dave Bevan / Swallow (Hirundo rustica) feeding juveniles perched on a rope near nest in a barn, Carmarthenshire, Wales, UK, September.

Dave Bevan / Pair of Swallows (Hirundo rustica) feeding chicks at nest in a barn, filmed using infra red, Carmarthenshire, Wales, UK, September.

Dave Bevan / Slow motion clip of a Swallow (Hirundo rustica) flying into a barn in heavy rain, Carmarthenshire, Wales, UK, September.

Tui De Roy / Swallow-tailed gull (Creagrus furcatus) Plazas Island, Galapagos

Tui De Roy / Swallow-tailed gull (Creagrus furcatus) calling, Genovesa Island, Galapagos

Tui De Roy / Swallow-tailed gull (Creagrus furcatus) in flight, Genovesa Island, Galapagos

Nick Upton / Little egret (Egretta garzetta) struggling to swallow a large Pike (Esox lucius) it has just caught, Rutland Water, Rutland, England, UK, November.

Ron Bielefeld/ BIA / Swallow-tailed Kite (Elanoides forficatus) flying, Florida

Ole Jorgen Liodden / Barn swallow (Hirundo rustica) in mud collecting nesting material, collecting nesting material, with golden bokeh affect in puddle, Svalbard, Norway, June.