Tsiribihina

The Tsiribihina is a river of western Madagascar. Its basin has an area of 49,800 square kilometres (19,200 mi2), and with a mean annual discharge of around 32 cubic kilometres (7.7 mi3) it is the largest river in Madagascar by volume.

The main tributaries are the Mahajilo, Manandaza, Mania, and Sakeny rivers. 7,025 square kilometres (2,712 mi2) is in the basin of the Sakeny River, 14,500 square kilometres (5,600 mi2) in that of the Mahajilo River, and 18,565 square kilometres (7,168 mi2) in that of the Mania River.

The headwaters are on Madagascar's Central Highlands. The tributary streams flow generally westwards except for the Sakeny, which flows northwards. As they leave the highlands and enter the north–south running Betsiriry Plain, the tributary rivers converge to form the Tsiribihina – the Mahajilo and Manandaza from the north, and the Mania and Sakeny from the south. There are extensive seasonal wetlands and shallow lakes where the rivers converge on the plain. The rich alluvial soils of the Betsiriry Plain make it one of the most suitable regions for agriculture in western Madagascar. The plain's wetlands and lakes are important habitat for waterbirds.