The site is located 60 km from Antsalova and 8 km from the Mozambique Channel. It comprises a vast complex of shallow lakes (less than 2 m deep) and marshes on alluvial soil, located to the west of the Bemaraha Tsingy National Park (IBA MG037). In the north and the east, the Beboka and Soahany rivers feed the complex. Water-bodies in the northern part are freshwater and seasonal, not holding water after July, while the central and southern water-bodies are permanent but increasingly saline towards the south. The wetlands in the north have been converted to rice-fields, while the central area is almost entirely covered by very dense, 2-m-high beds of reed-mace Typha, and the southern area by Typha, rushes Juncus, aquatic grasses and reeds.
See Box and Tables 2 and 3 for key species. One hundred and thirteen species are known from the site, of which 31 are endemic to Madagascar. Bemamba is the only site recently known for Amaurornis olivieri, and it is also of primary importance for Anas bernieri. There are also large breeding colonies of other waterbirds. This is the only site which holds all of the restricted-range species characteristic of the western wetlands of Madagascar.
In 1990, a cyclone partially blocked the Soahany river and this significantly reduced the inflow of fresh water. The conversion of marshes to rice-fields, fishing, deforestation, and palm-wine production are responsible for the destruction of large areas of vegetation. This is exposing the lakes to increased sedimentation, resulting from soil erosion, which constitutes a serious threat to the wetlands and their fauna. There is also considerable pressure on large waterbird colonies through hunting and egg-collection.
BirdLife International (2021) Important Bird Areas factsheet: Bemamba Wetland Complex. Downloaded from
http://www.birdlife.org on 27/10/2021.