Coordinates: 12°39′0″N 10°35′30″E / 12.65000°N 10.59167°E
The Hadejia-Nguru wetlands in Yobe State in northern Nigeria, which include Nguru Lake, are ecologically and economically important. They are threatened by reduced rainfall in recent years, a growing population and upstream dam construction.
The wetlands lie in the Yobe-Komadugu sub-basin of the Chad Basin. They are formed where the Hadejia and Jama'are rivers meet lines of ancient sand dunes in a northeast-southwest alignment and break into numerous channels. They are drained by the Yobe River, which flows east towards Lake Chad. They lie between Sudanian Savanna to the south and the drier Sahel to the north. Some of the land is permanently flooded, while other parts are flooded only in the wet season (August and September). Annual rainfall ranges between 200–600 mm, during the period late May–September. At one time the wetlands may have covered up to 3,000 km2. Between 1964 and 1971 over 2,000 km2 were flooded. By 1983 less than 900 km2 were flooded, and less than 300 km2 were flooded in the drought year of 1984.
The Hadejia-Nguru wetlands are on the List of Ramsar wetlands of international importance. Nguru Lake and the Marma Channel complex (58,100 ha) are designated a Ramsar Site. The wetlands are important for waterbirds, both for breeding species and for wintering and passage Palearctic waterbirds. The estimated waterbird population varies between 200,000 and 325,000. 377 bird species have been seen in the wetlands, including occasional sightings of the near-threatened pallid harrier and great snipe species.