Gabriel Rojo / Geoffroy's cat (Leopardus geoffroyi) walking past seaweed covered rocks on beach, Punta Norte Nature Reserve, Peninsula Valdes, Chubut Province, Patagonia, Argentina.

Gabriel Rojo / Geoffroy's cat (Leopardus geoffroyi) walking along beach with Gulls (Larus sp.) in background, Punta Norte Nature Reserve, Peninsula Valdes, Chubut Province, Patagonia, Argentina.

George Sanker / Coyote (Canis latrans) hunting in a wetland meadow in summer, Yellowstone National Park, Wyoming, USA. June.

Jussi Murtosaari / Two Brown bear (Ursus arctos) males, fighting, Finland. August.

Jussi Murtosaari / Grey wolf (Canis lupus) shaking fur dry after swimming, Finland. August.

Mark Carwardine / Brown bear (Ursus arctos) female, standing at edge of river, Great Bear Rainforest, British Columbia, Canada. October.

Joel Sartore / Photo Ark / Grandidier's mongoose / Grandidier's vontsira (Galidictis grandidieri) looking around, Al Bustan Zoological Centre. Captive. Endangered.

Joel Sartore / Photo Ark / Hawaiian monk seal (Neomonachus schauinslandi) vocalising. The animal's head appears from bottom of the frame. Minnesota Zoo. Captive. Endangered.

Joel Sartore / Photo Ark / Marbled cat (Pardofelis marmorata longicaudata) looking towards the camera and lying down. The animal hisses and bares its teeth. Al Bustan Zoological Centre, Sharjah. Captive.

Joel Sartore / Photo Ark / Eastern black bear (Ursus americanus americanus) juvenile, four months old, looking at the camera and moving curiously towards the camera, North Carolina Zoo Wildlife Rehabilitation Center, USA. Contr...

Matthew Maran / Red fox siblings (Vulpes vulpes) fighting on an allotment, London, England.

Matthew Maran / Red fox (Vulpes vulpes) peering through a hole in a garden fence at night, London, England. Taking using a camera trap.

Matthew Maran / Red fox (Vulpes vulpes) playing with a child's ball on an allotment, London, England.

Matthew Maran / Red fox cub (Vulpes vulpes) in allotment, London, England.

Matthew Maran / Red fox cub (Vulpes vulpes) drinking from a trough on allotment, London, England.

Matthew Maran / Red fox cub (Vulpes vulpes) on allotment at dusk, London, England.

Matthew Maran / Red fox cub (Vulpes vulpes) peers out from behind water trough on allotment, London, England.

Sven Zacek / Red fox (Vulpes vulpes) juvenile, sitting on rocks along the shore, Laane-Virumaa county, Northern Estonia.

Sven Zacek / Two Red fox (Vulpes vulpes) juveniles, sitting in dewy meadow at sunrise, Valgamaa county, Southern Estonia.

Lorraine Bennery / Ring-tailed mongoose (Galidia elegans) leaping, Montagne D'Ambre National Park, Madagascar.

Danny Green / Polar bear (Ursus maritimus) male, walking across snow covered landscape with mountains in background, Svalbard, Norway. April.

Danny Green / Ringed seal (Pusa hispida) pup, resting on ice, Svalbard, Norway. April.

Andrew Parkinson / Bengal tiger (Panthera tigris tigris) female juvenile, displaying aggressive behaviour towards its father, Bandhavgarh National Park, India. Endangered.

Will Watson / Representation of Lion's (Panthera leo) head with raised paw representing evil on Eardisley Font, carved in the mid 12th century in the Romanesque style, Herefordshire, England, UK.

Mike Read / Eurasian otter (Lutra lutra) cub feeding on Velvet swimming crab (Necora puber) at the edge of Loch Linnhe, Kingairloch, Scotland, UK, May.

Mike Read / Eurasian otter (Lutra lutra) cub feeding on Velvet swimming crab (Necora puber) at the edge of Loch Linnhe, Kingairloch, Scotland, UK, May.

Nick Garbutt / Puma (Puma concolor) juvenile male, resting in deep snow, Torres del Paine National Park / Estancia Amarga, Patagonia, Chile. July.

Nick Garbutt / Puma (Puma concolor) juvenile male, resting in snow, looking up towards passing aeroplane, Torres del Paine National Park / Estancia Amarga, Patagonia, Chile. July.

Nick Garbutt / Puma (Puma concolor) female, walking along snow covered ridgeline with mist covered valley (inversion) and early morning light on the Torres del Paine Massif in background, Torres del Paine National P...

Bret Charman / African lion (Panthera leo) male, head portrait, showing unusual eye pigmentation, South Luangwa National Park, Zambia.

Bret Charman / Arctic fox (Vulpes lagopus) 'blue morph' standing in snow with Sea urchin (Echinoidea) prey in mouth with mountains behind, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / Arctic fox (Vulpes lagopus) 'blue morph' standing on snowy ridge, looking back, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / African wild dog (Lycaon pictus) dragging a dead Impala (Aepyceros melampus) from a shallow pool at the edge of the Luangwa River, South Luangwa National Park, Zambia.

Bret Charman / Two Arctic foxes (Vulpes lagopus) 'blue morph', in snow, female attacking male to defend her cubs, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / African wild dog (Lycaon pictus) standing on banks of the Luangwa River, South Luangwa National Park, Zambia.

Bret Charman / Wolverine (Gulo gulo) juvenile, standing on a log in forest, eastern Finland. June.

Bret Charman / Grey wolf (Canis lupus) male, portrait, Kuhmo, Finland, June.

Bret Charman / Grey wolf (Canis lupus) male, walking along track in marshland, Finland. June.

Bret Charman / African leopard (Panthera pardus) female juvenile, drinking at edge of waterhole, South Luangwa National Park, Zambia.

Bret Charman / Grey wolf (Canis lupus) male, standing in swampland in boreal forest, Kuhmo, Finland. July.

Bret Charman / Brown bear (Ursus arctos) juvenile, walking through forest, Dinaric Alps, Slovenia. September.

Bret Charman / African leopard (Panthera pardus) female juvenile, head portrait, South Luangwa National Park, Zambia.

Bret Charman / African leopard (Panthera pardus) female juvenile, walking over dry grassland, South Luangwa National Park, Zambia.

Bret Charman / Arctic fox (Vulpes lagopus) 'blue morph' walking through blizzard, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / Arctic fox (Vulpes lagopus) 'blue morph', portrait, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / Bengal tiger (Panthera tigris tigris) running through forest, Nagarhole National Park, Karnataka, India. Endangered.

Bret Charman / Bengal tiger (Panthera tigris tigris) stalking herd of Gaur (Bos gaurus) in forest, Nagarhole National Park, Karnataka, India. Endangered.

Bret Charman / Four Atlantic walruses (Odobenus rosmarus) swimming close to shore with colony resting in background, Nordaustlandet, Svalbard Archipelago, Norway. July.

Bret Charman / African leopard (Panthera pardus) crossing in front of vehicle headlights, slow motion pan, South Luangwa National Park, Zambia.

Bret Charman / Arctic fox (Vulpes lagopus) leaping up vertical rock face, hunting for food at seabird colony, Alkefjellet, Spitsbergen, Svalbard archipelago, Norway. July.

Bret Charman / Wolverine (Gulo gulo) standing among Common bilberry (Vaccinium myrtillus) on forest floor, Finland. June.

Bret Charman / Wolverine (Gulo gulo) standing on fallen tree in boreal forest, Finland. July.

Bret Charman / Arctic fox (Vulpes lagopus) 'blue morph' walking through blizzard, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / Grey wolf (Canis lupus) juvenile, standing in rain on the edge of marsh, Finland. May.

Bret Charman / African wild dog (Lycaon pictus) resting, portrait, Mana Pools National Park, Zimbabwe.

Bret Charman / Brown bear (Ursus arctos) juvenile, standing on top of rock outcrop in forest, Dinaric Alps, Slovenia. May.

Bret Charman / European brown bear (Ursos arctos) standing in forest, Dinaric Alps, Slovenia. May.

Bret Charman / Brown bear (Ursus arctos) walking through forest, Dinaric Alps, Slovenia. May.

Bret Charman / Serval (Leptailurus serval) hunting in long grass of the savanna, Mara Triangle, Kenya.

Bret Charman / European brown bear (Ursus arctos) standing in forest, Dinaric Alps, Slovenia. May.

Bret Charman / Dingo (Canis lupus dingo) resting in palm grove, Fraser Island, Queensland, Australia.

Bret Charman / Arctic fox (Vulpes lagopus) 'blue morph', sitting in snow field, portrait, Hornstrandir Nature Reserve, Iceland. March.

Bret Charman / European brown bear (Ursos arctos) standing in forest, Dinaric Alps, Slovenia. May.

Colin Varndell / Polecat (Mustela putorius) juvenile, lying dead in road after being hit by car, Dorset, UK. June.

Suzi Eszterhas / Meerkat (Suricata suricatta) carrying scorpion (Scorpiones) prey in mouth, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) pup aged 6 weeks, carrying frog (Anura) prey in mouth, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) looking up, watching birds in the sky, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) head portrait, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) leaping over water, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Three Meerkat (Suricata suricatta) pups, aged 3 weeks, standing alert, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Five Meerkat (Suricata suricatta) pups, aged 3 weeks, sitting side by side, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, suckling her pup, aged 3 weeks, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Three Meerkats (Suricata suricatta) standing alert on hind legs, with pups, aged 3 weeks, emerging from burrow, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, running over sandy ground with four pups, aged 2 weeks, following behind, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) pup aged 2 weeks, with insect prey in mouth, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, suckling her pups, aged 2 weeks, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, standing alert behind four pups, aged 2 weeks, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Walrus (Odobenus rosmarus) female and calf resting on sea ice, Svalbard, Norway. August.

Suzi Eszterhas / Walrus (Odobenus rosmarus) female with calf aged 2 years, resting on sea ice, Svalbard, Norway. July.

Suzi Eszterhas / Polar bear (Ursus maritimus) male, climbing out of the ocean, hunting seals on sea ice, Svalbard, Norway. August.

Suzi Eszterhas / Polar bear (Ursus maritimus) male, climbing out of the ocean, hunting seal on sea ice, Svalbard, Norway. August.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, sleeping on top of her pups, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) running across dry ground, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) standing alert on the head of wildlife worker sitting on the ground, Makgadikgadi Pans, Botswana. June, 2016.

Suzi Eszterhas / Meerkat (Suricata suricatta) returning to burrow carrying insect prey in mouth, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, suckling her pup, aged 3 weeks, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Five Meerkat (Suricata suricatta) pups, aged 3 weeks, sitting side by side, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Three Meerkat (Suricata suricatta) pups, aged 3 weeks, resting, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) standing on termite mound, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) pup, aged 2 weeks, walking over sandy ground, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) pup, aged 2 weeks, carrying insect prey in mouth, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, bringing food to her pups, aged 2 weeks, at entrance of burrow, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Meerkat (Suricata suricatta) female, resting with her brood of pups, aged 2 weeks, Makgadikgadi Pans, Botswana.

Suzi Eszterhas / Two Meerkat (Suricata suricatta) pups, aged 2 weeks, at entrance to burrow, Makgadikgadi Pans, Botswana.

Neil Aldridge / Spotted hyena (Crocuta crocuta) young adult standing and looking around, in early morning light. Another Spotted hyena runs in and through the frame. Okavango Delta, Botswana.

Neil Aldridge / Black-backed jackal (Canis mesomelas) watching and listening intensely, its ears twitching in response to the surrounding sound. Then the animal turns round and leaves the frame. Okavango Delta, Botsw...