Ismaele Tortella / Northern gannet (Morus bassanus) colony, chick climbing back into nest, with the midnight sun, Norway, July

Ismaele Tortella / Tracking shot of a Whooper swan (Cygnus cygnus) family walking, Lofoten, northern Norway, August.

Morley Read / Slow motion clip of a Mute swan (Cygnus olor) with three cygnets, Cornwall, England, UK, May.

Andy Rouse / African lion (Panthera leo) female carrying young cub, Masai Mara, Kenya, Africa. Highly commended in the African Wildlife Category of the Nature's Best Photography Competition 2019.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) two adults brooding chicks age 5 weeks, Antarctica. Highly commended in the Polar Passion Category of the Nature's Best Photography Awards 2019.

Morley Read / Close-up of Agua rica leaf frog (Phyllomedusa ecuatoriana) eggs after 18 days development, the tadpoles are fully developed and ready to hatch, Ecuador. Endangered.

Morley Read / Close-up of Agua rica leaf frog (Phyllomedusa ecuatoriana) eggs after 11 days development, showing beating heart and blood flowing over gills, Ecuador. Endangered.

Chase Dekker / Humpback Whale (Megaptera novaeangliae) calf breaching, Monterey Bay, California

Chase Dekker / Humpback Whale (Megaptera novaeangliae) calf breaching, Monterey Bay, California

Chase Dekker / Humpback Whale (Megaptera novaeangliae) calf breaching, Monterey Bay, California

Chase Dekker / African Lion (Panthera leo) cub, Masai Mara, Kenya

Gerry Ellis / Chimpanzee (Pan troglodytes) orphan Larry playing in tree, Ape Action Africa, Mefou Primate Sanctuary, Cameroon

Gerry Ellis / Chimpanzee (Pan troglodytes) orphans, Larry investigating Daphne's tongue, Ape Action Africa, Mefou Primate Sanctuary, Cameroon

Gerry Ellis / Chimpanzee (Pan troglodytes) orphan Larry, Ape Action Africa, Mefou Primate Sanctuary, Cameroon

Gerry Ellis / Chimpanzee (Pan troglodytes) orphan Larry playing in forest nursery, Ape Action Africa, Mefou Primate Sanctuary, Cameroon

Gerry Ellis / Chimpanzee (Pan troglodytes) orphan Larry scratching, Ape Action Africa, Mefou Primate Sanctuary, Cameroon

Jami Tarris / Golden Eagle (Aquila chrysaetos) huntress, Altai Mountains, Bayan Ulgii, Mongolia

Juergen & Christine Sohns / African Lion (Panthera leo) six week old cub, Tswalu Game Reserve, South Africa

Anup Shah / Eastern Chimpanzee (Pan troglodytes schweinfurthii) four year old infant male, named Gizmo, foraging for insects in log, Gombe National Park, Tanzania

Fiona Rogers / Eastern Chimpanzee (Pan troglodytes schweinfurthii) four year old infant male, named Gizmo, Gombe National Park, Tanzania

Fiona Rogers / Eastern Chimpanzee (Pan troglodytes schweinfurthii) four year old infant male, named Gizmo, Gombe National Park, Tanzania

Martin Willis / Budgerigar (Melopsittacus undulatus) father with begging chick at nest cavity, Queensland, Australia

Danny Green / Polar bear (Ursus maritimus) female resting with cubs on glacier. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) and two cubs feeding on Whale carcass. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) and cubs, standing on sea ice. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) and cubs resting on sea ice. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) female and cubs, one cub walking up slope of ice in foreground. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) and cubs feeding on Whale carcass. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) and cubs feeding on Whale carcass, on iceberg. Svalbard, Norway, July 2018.

Danny Green / RF - Polar bear (Ursus maritimus) cub walking in snow. Svalbard, Norway, April. (This image may be licensed either as rights managed or royalty free.)

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

Danny Green / Polar bear (Ursus maritimus) female and cubs play fighting. Svalbard, Norway, March 2018.

Danny Green / Polar bear (Ursus maritimus) group on ice, female and cubs feeding on Whale carcass. Svalbard, Norway, June 2018.

Danny Green / Polar bear (Ursus maritimus), two cubs playing, leaping across sea ice, reflected in water. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus), two cubs walking on sea ice. Svalbard, Norway, July.

Danny Green / Polar bear (Ursus maritimus) cub ready to jump down from pack ice. Svalbard, Norway, April.

Nick Garbutt / Sumatran pit viper (Trimeresurus sumatranus) juvenile on tree trunk, in tropical rainforest. Danum Valley, Sabah, Borneo, Malaysia.

Nick Garbutt / Puma (Puma concolor puma) young male standing with mouth open. Estancia Amarga, near Torres del Paine National Park, Patagonia, Chile. December.

Gabriel Rojo / Guanaco (Lama guanicoe) female and newborn baby, nose to nose in grassland. La Pampa Province, Argentina.

Alex Mustard / Dugong (Dugong dugon) male and juvenile Golden trevally (Gnathanodon speciosus) swimming over Seagrass (Halophila stipulacea) meadow. Marsa Nabaa, Marsa Alam, Egypt.

Alex Mustard / Green turtle (Chelonia mydas) resting on sea floor and two juvenile Golden trevally (Gnathanodon speciosus). Marsa El Shouna, Marsa Alam, Egypt.

Oscar Dewhurst / Mute swan (Cygnus olor), two cygnets sheltering under parent's wing. Richmond Park, London, England, UK. April.

Oscar Dewhurst / Mute swan (Cygnus olor) swimming with cygnets in misty lake in morning light. Richmond Park, London, England, UK. May.

Claudio Contreras / California condor (Gymnogyps californianus), two perched in tree, adult and juvenile. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico.

Felis Images / Asiatic lion (Panthera leo persica), female and cubs in morning light, cub biting mother's leg. Gir National Park, Gujarat, India. Photo Phillip Ross/Felis Images

David Tipling / Grey seal (Halichoerus grypus) pup, Horsey, Norfolk, England, UK, February.

Tony Wu / Humpback whale (Megaptera novaeangliae australis) female with suckling calf. Vava'u Islands, Tonga.

Tony Wu / Humpback whale (Megaptera novaeangliae australis) male calf playing at ocean surface after coming up to breathe. Vava'u Islands, Tonga.

Jack Dykinga / Burrowing owl (Athene cunicularia) female and ten chicks aged a few weeks. Marana, Arizona, USA. May.

Andy Rouse / Bengal tiger (Panthera tigris) male, sub-adult aged three years, face portrait. Ranthambhore National Park, India.

Tony Heald / Elephant (Loxodonta africana) calves playing, Etosha National Park,Namibia.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) egg hatching on father's feet. Atka Bay, Antarctica. August. Winner of the Portfolio category of the Wildlife Photographer of the Year Awards 2019.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) chick looking upwards to parents beak. Atka Bay, Antarctica. August. Winner of the Portfolio category of the Wildlife Photographer of the Year Awards 2019.

Andy Rouse / Bengal Tiger (Panthera tigris) family drinking from pool, Ranthambhore, India

Jordi Chias / Chinstrap penguin (Pygoscelis antarcticus) with chicks, Antarctic Peninsula, Antarctica.

Jordi Chias / Gentoo penguin (Pygoscelis papua) feeding chick, Antarctic Peninsula, Antarctica.

Jordi Chias / Gentoo penguin (Pygoscelis papua) feeding chick, Antarctic Peninsula, Antarctica.

Jordi Chias / Gentoo penguin (Pygoscelis papua) with chick, Port Charcot, Antarctic Peninsula, Antarctica.Antarctic Peninsula, Antarctica.

Jordi Chias / Humpback whale (Megaptera novaeangliae), adult and baby at surface, Antarctic Peninsula, Antarctica.

Jordi Chias / Humpback whale (Megaptera novaeangliae) surfacing with baby, Antarctic Peninsula, Antarctica.

Mark Raycroft / Woodland Caribou (Rangifer tarandus caribou) mother nursing calf, Newfoundland, Canada

Matthew Maran / Red fox (Vulpes vulpes) cub defending its kill (a large dead Brown rat (Rattus norvegicus)) from another cub, North London, UK. August.

Alex Mustard / California sea lion (Zalophus californianus) pups in an underwater cave. Los Islotes, La Paz, Baja California Sur, Mexico. Sea of Cortez, Gulf of California, East Pacific Ocean.

Nick Upton / Juvenile Goldenrod spider (Misumena vatia) camouflaged on a Common hogweed (Heracleum sphondylium) flowerhead, reacting to and catching a fly (Muscidae), Wiltshire, England, UK, June.

Ernie Janes / Celebes crested macaque (Macaca nigra) infant, captive.

Suzi Eszterhas / Leopard (Panthera pardus) one-year-old cub in tree, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) one-year-old cub, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) four-month-old cub in tree, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) four-month-old cub in tree, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cub nursing, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cubs playing, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cub, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) mother playing with her six-week-old cub, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) five-week-old cub playing with mother's tail, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) five-week-old cub playing with mother's tail, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) mother grooming five-week-old cub, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) five-week-old cub playing with mother, Jao Reserve, Botswana

Nigel Cattlin / Immature caterpillar of a codling moth (Cydia pomonell) eating its way through a gallery in a ripening apple fruit, Berkshire, July

Nigel Cattlin / Harlequin ladybird (Harmonia axyridis) larvae still with a raft of empty egg cases, June Berkshire, England, UK.

John Chan / Great horned owl (Bubo virginianus) chicks stretching and flapping their wings, Southern California, USA, May.

John Chan / Great horned owl (Bubo virginianus) chick watching for parents to return with food, Southern California, USA, June.

David Woodfall / Dunlin (Calidris alpina) small wader with young in machair. North Uist, Scotland, UK, June.

David Woodfall / Little tern (Sterna albifrons ) feeding sand eel (Hyperoplus spp) to young chick. Gronant Dunes, Denbighshire, Wales, UK, June.

John Shaw / Snow monkey or Japanese macaque (Macaca fuscata) female with baby clinging to her back. Jigokudani, Japan, February.

John Shaw / Common loon (Gavia immer) with a chick alongside. British Columbia, Canada. June.

Shane Gross / Larval flounder (possibly Laeops Kitahara) in the open ocean at night off Anilao, Philippines.

Shane Gross / Queen conch (Lobatus gigas) juvenile feeding on algae growing on Seagrass (Thalassia testudinum) blades. Eleuthera, Bahamas.

Shane Gross / Moorish idol (Zanclus cornutus) juvenile with transparent skin in the open ocean at night off Anilao, Philippines.

Shane Gross / A juvenile soldierfish, possibly a Crescent-tail bigeye (Priacanthus hamrur) in the open ocean at night off Anilao, Philippines.

Nick Upton / Captive reared juvenile White stork (Ciconia ciconia) in flight over the Knepp Estate soon after release, Sussex, UK, August 2019.

Nick Upton / Captive reared juvenile White stork (Ciconia ciconia) with a GPS tracker on its back in flight over the Knepp Estate soon after release, Sussex, UK, August 2019.

Andy Rouse / Galapagos sea lion, (Zalophus wollebaeki), pup on shore, Galapagos.

Andy Rouse / RF - African Lion, (Panthera leo), female with cub, Masai Mara, Kenya, Africa,

Doc White / Sea Otter, (Enhydra lutris), young male, Elkhorn Slough, California, USA. January

Jiri Lochman / Brush-tailed phascogale (Phascogale tapoatafa) female with young, Kingston Forest, Western Australia, October.

Nick Hawkins / A female American black bear (Ursus americanus) and her young cub, Nova Scotia, Canada. July.