Ugo Mellone / Colombian spider monkey (Ateles fusciceps rufiventris) female, carrying infant, climbing along branch, Marimonda, Necocli, Colombia. Endangered.

Ugo Mellone / Colombian spider monkey (Ateles fusciceps rufiventris) female, sitting on branch looking down, Marimonda, Necocli, Colombia. Endangered.

Ugo Mellone / Colombian spider monkey (Ateles fusciceps rufiventris) hanging between branches in forest, Marimonda, Necocli, Colombia. Endangered.

Ugo Mellone / Colombian spider monkey (Ateles fusciceps rufiventris) female, sitting in tree, Marimonda, Necocli, Colombia. Endangered.

Ugo Mellone / Colombian spider monkey (Ateles fusciceps rufiventris) juvenile male, aged 3 years, sitting in tree, Marimonda, Necocli, Colombia. Endangered.

Ugo Mellone / Cotton-top tamarin (Saguinus oedipus) sitting in tree, Marimonda, Necocli, Colombia. Critically endangered.

Ugo Mellone / Cotton-top tamarin (Saguinus oedipus) sitting in tree, Marimonda, Necocli, Colombia. Critically endangered.

Ugo Mellone / Cotton-top tamarin (Saguinus oedipus) sitting in tree, Marimonda, Necocli, Colombia. Critically endangered.

Joel Sartore / Photo Ark / Blue-headed macaw (Primolius couloni), Tracy Aviary and Botanical Gardens, Salt Lake City, Utah, USA. Captive.

Joel Sartore / Photo Ark / Blue-headed macaw (Primolius couloni), Tracy Aviary and Botanical Gardens, Salt Lake City, Utah, USA. Captive.

Joel Sartore / Photo Ark / Blue-headed macaw (Primolius couloni), Tracy Aviary and Botanical Gardens, Salt Lake City, Utah, USA. Captive.

Joel Sartore / Photo Ark / Blue-headed macaw (Primolius couloni), Tracy Aviary and Botanical Gardens, Salt Lake City, Utah, USA. Captive.

Joel Sartore / Photo Ark / Sunset lorikeet (Trichoglossus forsteni), Indianapolis Zoo, Indianapolis, Indiana, USA. Captive.

Joel Sartore / Photo Ark / Sunset lorikeet (Trichoglossus forsteni), Indianapolis Zoo, Indianapolis, Indiana, USA. Captive.

Nicolas Rakotopare / Sri Lankan elephant (Elephas maximus maximus) juvenile bathing and playing in water with herd, Yala National Park, Sri Lanka. March.

Nicolas Rakotopare / Tracking shot of Sri Lankan elephant (Elephas maximus maximus) juvenile drinking and walking through water with herd, Yala National Park, Sri Lanka. March.

Nicolas Rakotopare / Sri Lankan elephant (Elephas maximus maximus) mother foraging amongst vegetation. A calf is standing beside its mother for protection. Yala National Park, Sri Lanka. March.

Nicolas Rakotopare / Sri Lankan elephant (Elephas maximus maximus) herd, including a calf, feeding. The adults use their feet and trunks to gather vegetation. The calf is staying close to its mother for protection. Yala N...

Nicolas Rakotopare / Sri Lankan elephant (Elephas maximus maximus) mother feeding on grass. A calf is standing beside its mother for protection. Yala National Park, Sri Lanka. March.

Nicolas Rakotopare / Sri Lankan elephant (Elephas maximus maximus) mother feeding, using foot and trunk to gather the grass. A calf is standing beside its mother for protection. Yala National Park, Sri Lanka. March.

Nicolas Rakotopare / Sri Lankan elephant (Elephas maximus maximus) adults feeding, using their feet and trunks to gather the grass. A calf is standing behind its mother for protection. Yala National Park, Sri Lanka. March...

Solvin Zankl / Spangled tubeshoulder (Persparsia kopua) portrait. It has a unique shoulder organ - a sac filled with luminescent fluid located behind the gills. When threatened, this fish can release the fluid to di...

Tom Vierus / Group of Tawny nurse sharks (Nebrius ferrugineus) and Bull sharks (Carcharhinus leucas) congregating at baited dive site, Shark Reef Marine Reserve, Serua Province, Fiji, Pacific Ocean.

Tom Vierus / Tawny nurse shark (Nebrius ferrugineus) with a fishing hook in its mouth, head portrait, Shark Reef Marine Reserve, Viti Levu, Fiji, Pacific Ocean.

Tom Vierus / Sicklefin lemon shark (Negaprion acutidens) with Pilotfish, head portrait, Shark Reef Marine Reserve, Viti Levu, Fiji, Pacific Ocean. Endangered.

Grant Maslowski / Black robin (Petroica traversi) portrait, almost birds of the species are colour banded or ringed for monitoring, Rangatira Island, Chatham Islands, New Zealand.

Grant Maslowski / Black robin (Petroica traversi) perched on branch with mealworm in beak. This species is intensively monitored, almost all birds of the species are colour banded or ringed, Rangatira Island, Chatham I...

Grant Maslowski / Black robin (Petroica traversi) portrait, almost all birds of the species are colour banded or ringed for monitoring, Rangatira Island, Chatham Islands, New Zealand.

Grant Maslowski / Pitt shags (Phalacrocorax featherstoni) roosting on rocky ledge, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Pitt shags (Phalacrocorax featherstoni) roosting on rocky ledge, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) leucistic male, standing on rocky shoreline, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) leucistic male, feeding in a rockpool on a rocky shoreline, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) female, standing on rocky shoreline with lichen in the foreground, surrounded by cloud of small flies, Rangatira Island, Chatham Islands, New Zealand. Endanger...

Grant Maslowski / Red-crowned parakeet (Cyanoramphus novaezelandiae chathamensis) perched in tree feeding, Rangatira Island, Chatham Islands, New Zealand.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) male, perched on a rock, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) male, perched on a rock, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Black robin (Petroica traversi) perched on branch, almost all birds of the species are colour banded or ringed for monitoring, Rangatira Island, Chatham Islands, New Zealand.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) male, perched on rock, banded for conservation monitoring, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Chatham oystercatchers (Haematopus chathamensis) pair, standing on rocky shoreline, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Chatham oystercatcher (Haematopus chathamensis) standing on rocky shoreline, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) male, standing on rocky shoreline, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) male, perched on Kelp, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / Shore plover (Thinornis novaeseelandiae) male, standing on rocky shoreline, Rangatira Island, Chatham Islands, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) male, with mouth open wide, dominance display, on beach, Sandfly Bay, Dunedin, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) male, resting on a beach, Sandfly Bay, Dunedin, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) male, with mouth open wide, dominance display, on beach, Sandfly Bay, Dunedin, South Island, New Zealand. Endangered.

Grant Maslowski / Kea (Nestor notabilis) male, perched on rocky mountainside Southern Alps, South Island, New Zealand. Endangered.

Grant Maslowski / Kea (Nestor notabilis) male, perched on mountainside with a small glacier in the background on Fog Peak, Southern Alps, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) female, resting on beach after rolling in sand, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) sub-adult male, with mouth open, dominance display, on sandy shore of an estuary, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / Two New Zealand sea lions (Phocarctos hookeri) sub-adult male courting female with pup close by, in shallows of an estuary, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / Two New Zealand sea lions (Phocarctos hookeri) sub-adult male courting female with pup close by, in shallows of an estuary, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) pup in shallows of an estuary, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / Two New Zealand sea lions (Phocarctos hookeri) sub-adult male courting female in shallows of an estuary, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / Two New Zealand sea lions (Phocarctos hookeri) sub-adult male courting female in shallows of an estuary, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand sea lion (Phocarctos hookeri) female and pup in shallows of an estuary, wild, Catlins, South Island, New Zealand. Endangered.

Grant Maslowski / Two Campbell Island teals (Anas nesiotis) feeding in coastal stream under moonlight, Sealers Bay, Whenua Hou / Codfish Island, New Zealand.

Grant Maslowski / Campbell Island teal (Anas nesiotis) feeding in coastal stream under moonlight, Sealers Bay, Whenua Hou / Codfish Island, New Zealand.

Grant Maslowski / Kakapo (Strigops habroptilus) female aged 5 years, head portrait. This individual was raised in captivity but is now free to roam the island, Whenua Hou / Codfish Island, New Zealand. Critically endan...

Grant Maslowski / Kakapo (Strigops habroptilus) female aged 5 years, head portrait. This individual was raised in captivity but is now free to roam the island, Whenua Hou / Codfish Island, New Zealand. Critically endan...

Grant Maslowski / Kakapo (Strigops habroptilus) female aged 5 years, perched on branch. This individual was raised in captivity but is now free to roam the island, Whenua Hou / Codfish Island, New Zealand. Critically e...

Grant Maslowski / Two Kakapo (Strigops habroptilus) chicks in a nest cavity at the base of a large tree, Whenua Hou / Codfish Island, New Zealand. Critically endangered.

Grant Maslowski / Kakapo (Strigops habroptilus) female aged 5 years, portrait. This individual was raised in captivity but is now free to roam the island, Whenua Hou / Codfish Island, New Zealand. Critically endangered...

Grant Maslowski / Kakapo (Strigops habroptilus) freshly-hatched chick being held by a vet, Whenua Hou / Codfish Island, New Zealand. April, 2019. Critically endangered. Captive.

Grant Maslowski / Kakapo (Strigops habroptilus) freshly-hatched chick being held by a vet, Whenua Hou / Codfish Island, New Zealand. April, 2019. Critically endangered. Captive.

Grant Maslowski / Kakapo (Strigops habroptilus) freshly-hatched chick being fed by a vet, Whenua Hou / Codfish Island, New Zealand. April, 2019. Critically endangered. Captive.

Grant Maslowski / Photographer searching for New Zealand rock wren (Xenicus gilviventris) in cloud covered mountains, Lake Roe, Fiordland, South Island, New Zealand. March, 2019.

Grant Maslowski / A research assistant and a volunteer using bluetooth speakers to search for the New Zealand rock wren (Xenicus gilviventris) on mountainside, Lake Roe, Fiordland, South Island, New Zealand. March, 201...

Grant Maslowski / A research assistant using telemetry to search for a New Zealand rock wren (Xenicus gilviventris) that has a transmitter attached, at sunset, Lake Greaney, Haast Range, West Coast, New Zealand. March,...

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, with radio transmitter attached being held by researcher, Haast Range, West Coast, New Zealand. February, 2019. Endangered. Controlled conditions.

Grant Maslowski / A research assistant measuring the wing chord of a New Zealand rock wren (Xenicus gilviventris). The banding / ringing kit will be used to colour band the bird. Gertrude Valley, Fiordland, South Islan...

Grant Maslowski / Photographer looking for New Zealand rock wren (Xenicus gilviventris) nest on mountainside with remains of an avalanche behind. Fiordland, South Island, New Zealand. November, 2018.

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, perched on rock, Perth Valley, West Coast, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, perched on rock, Perth Valley, West Coast, South Island, New Zealand. Endangered.

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, being held by researcher with bird rings visible, Lake Greaney, Haast Range, West Coast, New Zealand. January, 2018. Endangered. Controlled condition...

Grant Maslowski / Fieldworkers removing New Zealand rock wrens (Xenicus gilviventris) from a mist-net on mountainside, Haast Range, West Coast, New Zealand. January, 2018. Endangered.

Grant Maslowski / A volunteer fieldworker sitting on craggy mountainside watching a New Zealand rock wren (Xenicus gilviventris) nest in the alpine tussock, herb and boulder fields of the Haast Range with Mt Alba in th...

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, perched at entrance to nest holding Alpine cicada prey in beak to feed chicks, Haast Range, West Coast, New Zealand. Endangered.

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, perched on rock with feather in beak to use as nesting material, Haast Range, West Coast, New Zealand. Endangered.

Grant Maslowski / New Zealand rock wren (Xenicus gilviventris) male, perched on rock with feather in beak to use as nesting material, Haast Range, West Coast, New Zealand. Endangered.

Grant Maslowski / Kea (Nestor notabilis) in flight over an alpine lake with Doubtful Sound in the background, Fiordland National Park, South Island, New Zealand. Endangered.

Yashpal Rathore / Indian leopard (Panthera pardus fusca) using the underpass of National Highway NH-44, the longest national highway in India, seen here passing through Pench Tiger Reserve, Madhya Pradesh, India.Contac...

Yashpal Rathore / Indian leopard (Panthera pardus fusca) using the underpass of National Highway NH-44, the longest national highway in India, seen here passing through Pench Tiger Reserve, Madhya Pradesh, India. Conta...

Yashpal Rathore / Indian leopard (Panthera pardus fusca) walking across a bridge over the Sharda canal system, one of the biggest and oldest irrigation systems of Uttar Pradesh. Pilibhit Tiger reserve, Terai region, In...

Yashpal Rathore / Indian leopard (Panthera pardus fusca) walking across a bridge over the Sharda canal system, one of the biggest and oldest irrigation systems of Uttar Pradesh. Pilibhit Tiger reserve, Terai region, In...

Pete Oxford / Agami heron (Agamia agami) wading through shallow water with fish prey in beak, Pantanal, Brazil.

Pete Oxford / Agami heron (Agamia agami) wading in shallow water, Pantanal, Brazil.

Pete Oxford / Jaguar (Panthera onca) standing among dense vegetation at water's edge, northern Pantanal, Mato Grosso, Brazil.

Richard Sidey / Black-browed albatrosses (Thalassarche melanophris) pair, courtship display, Falkland Islands. January.

Neil Aldridge / Hawksbill turtle (Eretmochelys imbricata) swimming over a damaged reef, South Ari Atoll, Maldives. Critically endangered.

Neil Aldridge / African elephant (Loxodonta africana) head portrait, Okavango Delta, Botswana. Endangered.

Maxime Aliaga / Giant otter (Pteronura brasiliensis) running through shallow water along riverbank, Pantanal, Mato Grosso, Brazil. Endangered.

Maxime Aliaga / Giant otter (Pteronura brasiliensis) running through shallow water along riverbank, Pantanal, Mato Grosso, Brazil. Endangered.

Maxime Aliaga / Hyacinth macaw (Anodorhynchus hyacinthinus) in flight, Pantanal, Mato Grosso, Brazil.

Maxime Aliaga / Two Hyacinth macaws (Anodorhynchus hyacinthinus) landing on branch, one squawking at the other, Pantanal, Mato Grosso, Brazil.

Maxime Aliaga / Jaguar (Panthera onca) running along a sandy beach, Pantanal, Mato Grosso, Brazil.