The Great South Aquatic Reserve of Gabon is located off the departments of Basse and Haute Banio, in the province of Nyanga, in the extreme south-west of Gabon. It stretches from the beach to 200 nautical miles (370 km) from the outer limit of the waters under Gabonese jurisdiction. The southern limit is contiguous with Congolese waters, and to the west, with international waters.

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Composed of a remarkable variation of depths, its bathymetry reaches almost four kilometers in depth. It was created as an protected area to ensure the protection of a migration corridor that plays an important part to the largest nesting population of leatherback turtles in the world. The area is also the scene of annual migrations of humpback whales and other species of marine mammals. The reserve is an eloquent testimony to a functional ecosystem.

 

The Great South Aquatic Reserve of Gabon is increasing the efforts to protect marine biodiversity initiated in 2002 when Mayumba National Park was created. It has an area of ​​27,518.1 km 2 which makes it the largest aquatic reserve in Africa.