Stretching along the north bank of the Gambia River, the biosphere reserve lies adjacent to Senegal's Delta de Saloum Biosphere Reserve in the north. Within its boundaries, mangroves dominate the coastal areas and riverbanks, whereas, downstream, striking red limestone formations punctuate tropical forests and open savannah woodland.

The biosphere reserve safeguards some of West Africa's last pristine mangrove forests, alongside the Bao Bolong Wetland Reserve and various State forests. Notably, the biosphere reserve encompasses a Ramsar wetland and the UNESCO World Heritage site Kunta Kinteh Island, historically known as a place where enslaved peoples were held before being transported to the Americas during the 16^th and 17^th centuries.

With a sprawling expanse of 1 937 km², the biosphere reserves is home to approximately 178 000 inhabitants, who make a living mostly with farming and fisheries. It is the first biosphere reserve to be designated in The Gambia.

Pied Kingfisher (Ceryle rudis), Niumi BiosphereReserve (Gambia)© Department of Parks and Wildlife Management, c/o Ministry of Environment, Climate Change and Natural Resources, GIEPA House. Kairaba Avenue

Bird census group on the coast of the Niumi Biosphere Reserve (Gambia)© Department of Parks and Wildlife Management, c/o Ministry of Environment, Climate Change and Natural Resources, GIEPA House. Kairaba Avenue

Local fish trade, Niumi BiosphereReserve (Gambia)© Department of Parks and Wildlife Management, c/o Ministry of Environment, Climate Change and Natural Resources, GIEPA House. Kairaba Avenue