Rapids in the Betsiboka River
|- left||Ikopa River|
|- right||Kamoro River|
|- elevation||1,755 m (5,758 ft)|
|- location||Bombetoka Bay, Mozambique Channel|
|Length||525 km (326 mi)|
|Volume||74.3 - 678 m3 (-23,869 cu ft)|
|Basin||11,800 km2 (4,556 sq mi)|
Betsiboka River is a 525-kilometre (326 mi) long river in central-north Madagascar. It flows northwestward and empties to Bombetoka Bay, forming a large delta. It originates to the east of Antananarivo. The river is surrounded in mangroves. The river is distinct for its red-coloured water, which is caused by river sediments. The river carries an enormous amount of reddish-orange silt to the sea. Much of this silt is deposited at the mouth of the river or in the bay.
It is dramatic evidence of the catastrophic erosion of northwestern Madagascar. Removal of the native forest for cultivation and pastureland during the past 50 years has led to massive annual soil losses approaching 250 metric tonnes per hectare (112 tons per acre) in some regions of the island, the largest amount recorded anywhere in the world. Several fish species are endemic to the river basin, including the three cichlids Paretroplus petiti, P. tsimoly and P. maculatus.
- Bradt, Hilary (17 May 2011). Madagascar: The Bradt Travel Guide. Bradt Travel Guides. p. 82. ISBN 978-1-84162-341-2. Retrieved 8 January 2013.
- Tsilavo Raharimahefa and Timothy M. Kusky (2010). "Environmental monitoring of bombetoka bay and the Betsiboka estuary, Madagascar, using multi-temporal satellite data".
- Floods in Madagascar at NASA Earth Observatory
- Sediment Laden Drainages at Lunar and Planetary Institute, USRA
- NASA: Earth from Space