Tony Heald / Hippopotamus (Hippopotamus amphibius) splashing in pool in evening light. Mana Pools National Park, Zimbabwe.

Guy Edwardes / Hippopotamus (Hippopotamus amphibius) in Chobe River, Botswana.

Bence Mate / Hippopotamus (Hippopotamus amphibius) at waterhole at night, Mkuze, South Africa Third place in the Nature Portfolio category of the World Press Photo Awards 2017.

Neil Aldridge / Hippopotamus (Hippopotamus amphibius) charging through the shallows, Chobe River, Chobe National Park, Botswana. Vulnerable species.

Wim van den Heever / Hippopotamus (Hippopotamus amphibius) out of the water, peering around vegetation. Okavango Delta, Botswana.

Pedro Narra / Hippopotamus (Hippopotamus amphibius) at water surface, Bijagos Archipelago Biosphere Reserve, Guinea Bissau,

Pedro Narra / Hippopotamus (Hippopotamus amphibius) with head raised above water surface, Bijagos Archipelago Biosphere Reserve, Guinea Bissau,

Staffan Widstrand / Hippopotamus (Hippopotamus amphibius) bull emerging from water to charge, iSimangaliso Wetland Park, KwaZulu Natal National Park. South Africa. Specially commended in the Animal Portraits category of...

Sharon Heald / Hippopotamus (Hippopotamus amphibius) charging, Chobe National Park, Botswana, July.

Tony Heald / Hippopotamus (Hippopotamus amphibius) charging, Chobe National Park, Botswana, July.

Enrique Lopez-Tapia / Hippopotamus (Hippopotamus amphibius) charging against boat on Lake Chamo. Nechisar National Park. Ethiopia, November 2014

Ole Jorgen Liodden / Hippopotamus (Hippopotamus amphibius) rearing head out of water, creating spray, Lake Naivasha, Kenya.