The Niger River is the principal river of western Africa, extending over 4180 km. It runs in a crescent through Guinea, Mali, Niger, on the border with Benin and then through Nigeria, discharging through a massive delta, known as the Oil Rivers, into the Gulf of Guinea.
The Niger is the third longest river in Africa, exceeded only by the Nile and the Congo River. Its main tributary is the Benue River.
An unusual feature of the river is the Niger Inland Delta, which forms where its gradient suddenly decreases. The result is a region of braided streams, marshes, and lakes the size of Belgium; the seasonal floods make the Delta extremely productive for both fishing and agriculture.
The Niger takes one of the most unusual routes of any major river, a boomerang shape that baffled European geographers for two millennia. Its source is just 150 miles (240 km) inland from the Atlantic Ocean, but the river runs away from the sea into the Sahara Desert, then takes a sharp right turn near the ancient city of Timbuktu (Tombouctou), Mali and heads southeast to the Gulf of Guinea.
A combination of human population growth (average 3% per year) and unsustainable resource use is threatening the Niger river’s current and future ability to support the basin’s rich biodiversity and provide resources to the communities living along its banks.
The effects of deforestation and farming of fragile soils is leading to sedimentation of river channels. The Niger, which is the third largest river in Africa, dried up completely for several weeks in 1985 at Malanville in the Benin Republic.
Habitat alterations are also threatening the rich tapestry of the Niger River ecosystem. These include dams, which drastically alter the flow and sediment regimes of the rivers in the basin in addition to directly fragmenting and destroying aquatic habitats; irrigated floodplain agriculture, which displaces productive habitat for fish, livestock, and wildlife; and increasing discharges of sewage and other anthropogenic pollutants into the rivers.