Ingo Arndt / Red-eyed tree frog (Agalychnis callidryas) eye closed with semi-transparent eyelid that allows it to see its surroundings even while resting, Costa Rica.

Bence Mate / Two Great egrets (Ardea alba) standing opposite each other with Grey heron (Ardea cinerea) in between. Lake Csaj, Pusztaszer, Hungary, January. Winner of the Portfolio category of the Terre Sauvage Na...

Bence Mate / Two Great egrets (Ardea alba) face to face against white sky, Lake Csaj, Pusztaszer, Hungary. Winner of the Portfolio category of the Terre Sauvage Nature Images Awards competition 2015.

Fabrice Cahez / Red fox (Vulpes vulpes) cub sitting, rear view, Vosges, France, May.

Franco Banfi / Walrus (Odobenus rosmarus) hauled out in shallow water, Spitsbergen, Svalbard Archipelago, Norway, Arctic Ocean. July.

Staffan Widstrand / Wild Wonders of China / Crested myna starlings (Arcidotheres cristatellus) sitting on domestic waterbuffaloes (Bubalus domesticus), Poyang Ho Lake, Jiangxi province, China

David Kjaer / Great bustard (Otis tarda) chicks hatched from eggs collected under licence from the Castilla-La Mancha region of Spain.

Frederique Olivier / Adelie penguins (Pygoscelis adeliae) in front of French Icebreaker L'Astrolabe, on edge of the fast ice off Dumont D'Urville station, Antarctica. December 2014.

Markus Varesvuo / Puffin (Fratercula arctica) silhouetted at sunset, Shetland Islands, Scotland, UK, July.

Nick Garbutt / Bare-faced Curassow (Crax fasciolata) male and female, Near Araras Lodge, Mato Grosso, Northern Pantanal, Brazil, South America.

Markus Varesvuo / Capercaillie (Tetrao urogallus) male calling with female, Jalasjarvi, Finland, April

Ben Cranke / Walrus (Odobenus rosmarus) portrait, Svalbard, Norway. July.