Mandrill Troop — Lopé National Park Gabon

The rainforests of Lopé National Park in central Gabon host one of Africa's most extraordinary and least-known wildlife spectacles — supertroop aggregations of up to 1,300 mandrills, the world's largest monkey, gathering in single groups that move through the forest like a colourful army, the dominant males' extraordinary facial colouration — vivid blue and red ridged muzzle, golden beard, and the multi-coloured hindquarters of sexually active males — creating a primate spectacle of tropical extravagance unmatched anywhere in Africa. Mandrill supertroop aggregations are among the largest primate gatherings on Earth and their movement through the Lopé forest — heard as a continuous rustling and calling from a kilometre away before they come into view — creates one of the Congo Basin's most thrilling wildlife moments for the handful of researchers and privileged visitors who access this remote Gabonese park. The Lopé's forest-savannah mosaic landscape — a relict landscape from drier Pleistocene climates — provides the open areas where mandrills are most visible when foraging, and the combination of their visibility and their extraordinary colouration creates one of wildlife photography's most coveted African primate subjects. The park additionally harbours forest elephants, western lowland gorillas, and chimpanzees in a central African forest ecosystem of remarkable completeness.