Tiwai Island Wildlife Sanctuary

Tiwai Island Wildlife Sanctuary is a 12-square-kilometre island reserve in the Moa River, in the Southern Province of Sierra Leone. It protects a tract of Upper Guinean rainforest and is known for an exceptionally high density of primates, including the Diana monkey and the western chimpanzee.

The island has hosted a biological research station since the early 1980s and is managed in partnership with surrounding communities. The nearby river forests are also associated with the rare and elusive pygmy hippopotamus.

Visitors typically join guided forest walks, night walks, and river boat trips, with birdwatching a draw throughout. Basic community-run accommodation is available on the island, and access is by boat from the riverbank.