sentences:  The drastic reduction in the flow of the river led to a 40% reduction in the coverage of mangroves, greatly increased erosion of the coastal region and a 60% reduction in the catch of prawns off the mouth due to the reduction in emplacement of silt and associate nutrients.Wetland ecosystems downstream of the dam shrank considerably.Wildlife in the delta was further threatened by uncontrolled hunting during the civil war in Mozambique.