Claudio Contreras / California condor (Gymnogyps californianus), portrait. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico.

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

Paul Souders/ Worldfoto / African Elephant (Loxodonta africana) calf feeding, Ngorongoro Conservation Area, Tanzania

Paul Souders/ Worldfoto / Grey Crowned Crane (Balearica regulorum) flying, Ngorongoro Conservation Area, Tanzania

Doug Gimesy / Platypus (Ornithorhynchus anatinus) in early morning light on Lake Elizabeth, Great Otway National Park, near Forrest, Victoria, Australia, July 2017.

Christophe Courteau / Mountain gorilla (Gorilla beringei beringei) silverback sitting on boundary wall between Volcanoes National Park and a Potato crop, looking into valley. Area to be restored to forest. Rwanda.

Axel Gomille / Wolf (Canis lupus), sitting in front of wrecked tank, military training area, Saxony-Anhalt, Germany

Will Burrard-Lucas / Black and white image of African elephant (Loxodonta africana) Tsavo Conservation Area, Kenya. Taken with a remote camera buggy / BeetleCam. Editorial use only.

Will Burrard-Lucas / Black and white image of African elephant (Loxodonta africana) herd with calf at waterhole, seen through adults legs. Tsavo Conservation Area, Kenya. Taken with a remote camera buggy / BeetleCam. Edit...

Will Burrard-Lucas / Black and white image of African elephant (Loxodonta africana) bulls males facing off against each other, Tsavo Conservation Area, Kenya. Editorial use only.

Will Burrard-Lucas / Black and white image of African elephant (Loxodonta africana) mud bathing, Tsavo Conservation Area, Kenya. Editorial use only.

Nick Garbutt / Pack of wolves (Canis lupus). Yellowstone National Park, Wyoming, USA. January.