Canvey Island the 30 hectares known as West Canvey marshes, acquired by the RSPB in 2007, and the Canvey Wick nature reserve. Canvey Wick is a designated Site of Special Scientific Interest (SSSI) at the site of the abandoned and incomplete oil refinery. The foundations of the 100 hectare (0.4 sq mile) site were prepared in the 1970s by laying thousands of tonnes of silt dredged from the Thames; the abandoned and undisturbed area has flourished as a haven for around 1,300 species of wildlife, many of which are endangered or were thought to be extinct; including the shrill carder bee, the
Wouri estuary Wouri estuary The Wouri estuary, or Cameroon estuary is a large tidal estuary in Cameroon where several rivers come together, emptying into the Bight of Biafra. Douala, the largest city in Cameroon, is at the mouth of the Wouri River where it enters the estuary. The estuary contains extensive mangrove forests, which are being damaged by pollution and population pressures. The estuary lies to the east of Mount Cameroon and empties into the Bight of Biafra. It is fed by the Mungo, Wouri and Dibamba rivers. The estuary lies in the Douala Basin, a low-lying depression about on average about