Betsiboka River

In central-north Madagascar, the Betsiboka River is a 525-kilometer (326-mile) long river. it ranks 3rd among the longest rivers in Madagascar. It runs northwest to Bombetoka Bay, where it empties into a vast delta. Its source is located east of Antananarivo. Mangroves border the river on all sides. The river is known for its unusual reddish-brown water, which is caused by river sediments. The river transports a large quantity of reddish-orange sediment to the sea. The majority of the silt is deposited at the river's mouth or in the bay.

It's a stark example of northwestern Madagascar's disastrous erosion. Over the last 50 years, the removal of native forest for farming and pastureland has resulted in huge yearly soil losses of up to 250 metric tons per hectare (112 tons per acre) in some areas of the island, the highest quantity ever recorded anywhere on the planet. Several fish species, including the three cichlids Paretroplus petiti, P. tsimoly, and P. maculatus, are indigenous to the river basin.

The Ikopa River, the Betsiboka's main tributary, drains Antananarivo's capital city.

Length: 525 km (326 mi)