Tim Fitzharris / Siberian Tiger (Panthera tigris altaica) running, native to Russia

Staffan Widstrand / Polar Bear (Ursus maritimus) reflection in water, Svalbard, Norway

Norbert Wu / Oceanic White-tip Shark (Carcharhinus longimanus) with Pilot Fish (Naucrates ductor), Bahamas, Caribbean

Suzi Eszterhas / Mountain Gorilla (Gorilla gorilla beringei) silverback feeding, Parc National des Volcans, Rwanda

Suzi Eszterhas / Mountain Gorilla (Gorilla gorilla beringei) mother holding five month old twin babies, Parc National des Volcans, Rwanda

Suzi Eszterhas / Mountain Gorilla (Gorilla gorilla beringei) mother holding five month old twin babies, Parc National des Volcans, Rwanda

Kevin Schafer / Galapagos Sea Lion (Zalophus wollebaeki) pups playing, Espanola Island, Galapagos Islands, Ecuador

Ingo Arndt / Shoebill (Balaeniceps rex), Uganda

XI ZHINONG / Tibetan antelope (Pantholops hodgsonii) male, Kekexili, Qinghai, Tibetan Plateau, China, November

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) with rainbow and storm clouds. Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) with rainbow and storm clouds. Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) grazing. Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) grazing. Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) grazing. Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) grazing. Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) grazing, Ol Pejeta Conservancy, Kenya, 2009. Threatened species.

Mark Carwardine / Southern white rhinoceros (Ceratotherium simum simum) wild animal with ranger providing round-the-clock protection. Ol Pejeta Conservancy, Kenya, 2009. Threatened species, Model released

Mark Carwardine / Two Humpback whales (Megaptera novaeangliae) bubble-net feeding very close to shore, Great Bear Rainforest, British Columbia, Canada, Endangered or threatened species (Vulnerable)

Mark Carwardine / Humpback whales (Megaptera novaeangliae) feeding on herring, showing palate and baleen plates, Frederick Sound, South East Alaska, USA, Endangered or threatened species (Vulnerable)

Mark Carwardine / Amazon river dolphin, pink river dolphin or boto (Inia geoffrensis) Rio Negro, Brazil (Amazon) - wild animal breaching Threatened species (IUCN Red List)

Mark Carwardine / Amazon / Pink river dolphin / Boto {Inia geoffrensis} Rio Negro, Amazon, Brazil Threatened species (IUCN Red List)

Mark Carwardine / Amazon / pink river dolphin / boto (Inia geoffrensis) Rio Negro, Brazil (Amazon) wild animal breaching, Threatened species (IUCN Red List)

Mark Carwardine / Amazon / Pink river dolphin / Boto {Inia geoffrensis} breaching, Rio Negro, Amazon, Brazil Threatened species (IUCN Red List)

Mark Carwardine / Amazon river dolphin, pink river dolphin or boto (Inia geoffrensis) Rio Negro, Brazil (Amazon) - two wild animals fighting over fish Threatened species (IUCN Red List)

Mark Carwardine / Amazon / pink river dolphin / boto (Inia geoffrensis) Rio Negro, Brazil (Amazon) wild animal underwater in tannin rich river, Threatened species (IUCN Red List)

Mark Carwardine / Amazon / pink river dolphin / boto (Inia geoffrensis) Rio Negro, Brazil (Amazon) wild animal underwater in tannin rich river, Threatened species (IUCN Red List)

Mark Carwardine / Amazon / pink river dolphin / boto (Inia geoffrensis) Rio Negro, Brazil (Amazon) wild animal underwater in tannin rich river, Threatened species (IUCN Red List)

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) six week old cub on sleeping mother at den, Bandhavgarh National Park, India

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) six week old cub on mother paw at den, Bandhavgarh National Park, India

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) five week old cub resting on sleeping mother at den, Bandhavgarh National Park, India

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) mother and four week old cubs at den, Bandhavgarh National Park, India

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) mother and four week old cubs at den, Bandhavgarh National Park, India

Christophe Courteau / West African giraffe male feeding {Giraffa camelopardis peralta}. Sahel, Niger.

Christophe Courteau / West African giraffes {Giraffa camelopardalis peralta}. Dallol Bosso Nord, Sahel, Niger.

Christophe Courteau / West African giraffe calf {Giraffa camelopardalis peralta}, Niger.

Christophe Courteau / West African giraffe face {Giraffa camelopardis peralta}. Sahel, Niger.

Mark Carwardine / Marine Iguanas (Amblyrhynchus cristatus), the only marine lizard, basking on volcanic rocks. Galapagos Islands, Ecuador, South America. Book plate from Mark Carwardine's Ultimate Wildlife Experiences.

Pete Oxford / San Lucas marsupial frog (Gastrotheca pseustes) base of Chimborazo Volcano (Highest mountain in Ecuador), Andes, Ecuador, South America - endemic to Ecuador, endangered species.

Pete Oxford / Eastern indigo snake (Drymarchon couperi) The Orianne Indigo Snake Preserve, Telfair County, Georgia, USA, threatened species, captive

Chien Lee / Komodo Dragon (Varanus komodoensis) in grass, Nusa Tenggara, Indonesia

Bert Willaert / Trivandrum / Golden Frog (Hylarana aurantiaca) looking upwards. Western Ghats, India.

Theo Allofs / African Elephant (Loxodonta africana), Skeleton Coast, Namib Desert, Namibia

Theo Allofs / African Elephant (Loxodonta africana) herd crossing desert, Skeleton Coast, Namib Desert, Namibia

Theo Allofs / African Elephant (Loxodonta africana) female and calves crossing desert, Skeleton Coast, Namib Desert, Namibia

Norbert Wu / Whale Shark (Rhincodon typus) feeding on plankton off Isla Mujeres, Mexico

Pete Oxford / African Lion (Panthera leo) male portrait, Moremi Game Reserve, Okavango Delta, Botswana

Steven Kazlowski / Polar bear (Ursus maritimus) curious adult investigates a remote camera along a hillside on Spitsbergen and the northwest coast of the Svalbard Archipelago, Norway, Greenland Sea, July

Andrew Parkinson / 2020VISION / Marsh harrier (Circus aeruginosus) chick, removed from its nest to be sexed, weighed and ringed by licensed professional, Phil Littler, held up to be photographed by reserve volunteers, Sculthorpe Nat...

Andrew Parkinson / 2020VISION / Marsh harrier (Circus aeruginosus) chick at its nest site, defiant as it is approached by a licenced bird ringer, Sculthorpe Nature Reserve, Norfolk, UK, July 2010

Andrew Parkinson / 2020VISION / Marsh harrier (Circus aeruginosus) three sub-adult siblings squabbling in flight in the last rays of evening sunlight, Norfolk, UK, August

Mark Carwardine / Jaguar (Panthera onca), one-year cub peering from behind tree, Cuiaba River, Pantanal, Brazil. near threatened species

Andrew Parkinson / Red squirrel (Sciurus vulgaris) standing on its hind legs, Cairngorms National Park, Scotland, UK, March.

Andrew Parkinson / Red squirrel (Sciurus vulgaris) in snow, Cairngorms National Park, Scotland, UK, March.

Andrew Parkinson / Rear view of Red squirrel tail (Sciurus vulgaris) foraging in deep snow, Cairngorms National Park, Scotland, UK, March.

Andrew Parkinson / Red squirrel (Sciurus vulgaris) standing on its hind legs, Cairngorms National Park, Scotland, UK, March.

Andrew Parkinson / Red squirrel (Sciurus vulgaris) portrait in snow, Cairngorms National Park, Scotland, UK, March.

Andrew Parkinson / Red squirrel (Sciurus vulgaris) adult backlit by winter sunlight, Formby Point, Lancashire, UK, December.

Mark Hamblin / 2020VISION / Close up of hands of woman 'hugging' Scots pine tree (Pinus sylvestris), Abernethy Forest, Cairngorms National Park, Scotland, UK, August 2010, Model released. 2020VISION Book Plate. Did you know? The...

Daniel Heuclin / Pyrenean mountain newt / brook salamander (Calotriton / Euproctus asper) mating pair, captive, from Pyreneen mountains, France and Spain, near threatened

Nuno Sa / Great Blue Shark (Prionace glauca), dorsal view against dark water. Over 20 million Blue Sharks are fished annually, as bycatch and due to the high value of their fins. Azores, North Atlantic, Septemb...

Juergen Freund / Green turtles (Chelonia mydas) mating over coral reef, Sipadan Island, Sabah, Malaysia, June, Endangered species

Juergen Freund / Baby green turtle (Chelonia mydas) hatchling in the shallows of the beach, swimming out to sea. Anano Island, Wakatobi, South Sulawesi, Indonesia, November

Andy Rouse / Polar Bear (Ursus maritimus) mother and two cubs playing around iceberg. Svalbard, Norway, Europe, February.

Andy Rouse / close up portrait of a Polar Bear (Ursus maritimus), about three year. Svalbard, Norway, Europe, February.

Andy Rouse / Polar Bear (Ursus maritimus) large male on pack ice. Svalbard, Norway, Europe, February.

Andy Rouse / Polar Bear (Ursus maritimus) mother standing on hind legs, and cub (18 months old). Svalbard, Norway, Europe, February.

Andy Rouse / Two Polar Bears (Ursus maritimus) swimming. Svalbard, Norway, Europe, February.

Andy Rouse / Two Polar Bear (Ursus maritimus) new year cubs (6 months). Svalbard, Norway, Europe, February.

Hiroya Minakuchi / Fin Whale (Balaenoptera physalus) near surface, Baja California, Mexico

Hiroya Minakuchi / Sperm Whale (Physeter macrocephalus) calf swimming near water surface, Ogasawara Island, Japan

ZSSD / Rothschild Giraffe (Giraffa camelopardalis rothschildi), native to Africa

ZSSD / Rothschild Giraffe (Giraffa camelopardalis rothschildi) calf, native to Africa

ZSSD / Rothschild Giraffe (Giraffa camelopardalis rothschildi) mother and calf nuzzling, native to Africa

Richard Du Toit / African Elephant (Loxodonta africana) calf smelling the air, Chobe National Park, Botswana

Ian Coleman / Illustration of Grey reef shark (Carcharhinus amblyrhynchos), Carcharhinidae. Endangered / threatened species.

Ian Coleman / Illustration of Basking shark (Cetorhinus maximus) feeding. Endangered / threatened species.

Ian Coleman / Illustration of Common thresher shark (Alopias vulpinus), Alopiidae. Endangered / threatened species.

Ian Coleman / Illustration of Great white shark (Carcharodon carcharias), Lamnidae. Endangered / threatened species.

Tui De Roy / Reticulated Giraffe (Giraffa reticulata) mother and calves, Ol Pejeta Conservancy, Kenya

Tui De Roy / African Elephant (Loxodonta africana) trio, Ol Pejeta Conservancy, Kenya

Mark Carwardine / Black rhinoceros (Diceros bicornis) - darted and being prepared for translocation by rangers from the Kenya Wildlife Service, being measured Nairobi National Park, Kenya, Endangered / threatened spec...

Thomas Marent / Bornean White-bearded Gibbon (Hylobates albibarbis) walking on liana, Tanjung Puting National Park, Borneo, Indonesia

Thomas Marent / Bornean White-bearded Gibbon (Hylobates albibarbis), Tanjung Puting National Park, Borneo, Indonesia

Konrad Wothe / Australian Red Claw Crayfish (Cherax quadricarinatus), Daintree National Park, North Queensland, Queensland, Australia

Winfried Wisniewski / African Elephant (Loxodonta africana) males sparring, Chobe National Park, Botswana

Winfried Wisniewski / African Elephant (Loxodonta africana) and tourist boat, Chobe River, Chobe National Park, Botswana

Vincent Grafhorst / African Lion (Panthera leo) pair mating, Khutse Game Reserve, Botswana

Vincent Grafhorst / African Lion (Panthera leo) male, Khutse Game Reserve, Botswana

Vincent Grafhorst / African Lion (Panthera leo) male and female courting, Khutse Game Reserve, Botswana

Jim Brandenburg / Black-footed Ferret (Mustela nigripes) smelling ground, Wyoming

Mark Carwardine / Pink pigeon (Columba / Nesoenas mayeri) threatened / endangered species, Black River Gorges, Mauritius, Indian Ocean, wild

Mark Carwardine / Pink pigeon (Columba / Nesoenas mayeri) threatened / endangered species, Black River Gorges, Mauritius, Indian Ocean, wild

Mark Carwardine / Pink pigeon (Columba / Nesoenas mayeri) threatened / endangered species, Black River Gorges, Mauritius, Indian Ocean, wild

Mark Carwardine / Mauritius / Mascarene / Echo parakeet (Psittacula eques) flying, threatened / endangered species, Black River Gorges, Mauritius, Indian Ocean, wild