Purus River

The Purus River, which rises in several headwaters in Peru, is a tributary of the Amazon River. The river flows through the Amazon Rainforest until it merges with the Amazon upstream from Manaus, Brazil. Much of its 3,211 km (1,995 mi) course is navigable.

The river’s headwaters arise from the Ucayali Basin at 520 m (1,700 ft) above sea level. The river has two main tributaries, Rio Curiuja and Rio Cujar, which rise in the Purus Province of Peru. From the confluence point, the river meanders northeastwards to Brazil, then defines the Peru-Brazil border in the Brazilian state of Acre.

The Purus receives the Santa Rosa River and continues slowly meandering through the Amazon Rainforest, flowing through a great depression separating the Ucayali and Madeira Rivers. Finally, it crosses into Amazonas state, Brazil, and flows past the towns of Pauini, Labrea, and Canutama.

After entering Amazonas state, the river meanders sluggishly northward, eastward and northeastward until it joins the stretch of the Amazon upstream from Manaus, known as the Solimões River.

Along its course, the river either passes by or courses through several protected areas in Brazil:

• Santa Rosa do Purus National Forest

• Arapixi Extractive Reserve

• Purus National Forest

• Médio Purus Extractive Reserve

• Canutama Extractive Reserve

• Piagaçu-Purus Sustainable Development Reserve

Purus Basin

The Purus Basin, located in the southwestern Amazon depression, is shared by Brazil and Peru and is one of the most important watersheds of the Solimões-Amazon River.

The Purus River is the basin’s most outstanding hydrological feature and drains approximately 365,000 sq km (140,000 sq mi). About 90% of the drainage basin lies in the states of Acre and Amazonas in Brazil.

The river, which is highly meandering, has massive floodplains and is flanked by numerous lakes near its shores. Wetlands cover approximately 40,000 sq km (15,000 sq mi) of the drainage basin’s total area.

Biology

The river and basin have a rich biodiversity. The Purus red howler (Alouatta puruensis) is a species of howler monkey found in forested areas along the river bank. Various bird species, including egrets, blue herons, green parrots, and macaws, visit and nest in the area. Reptiles like the Boa constrictors and water lizards are common in the basin.

_{Map depicting the Amazon basin with the Purus River highlighted}