· Rich Whitewaters
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
· Looking Ahead

Global 200 Snapshot

The Orinoco River and Flooded Forests ecoregion contains a rich diversity of freshwater fish and several habitat types that are rare worldwide. A majority of the fish species in this species-rich ecoregion lives only in this ecoregion and often within a small area of it.  

Rich Whitewaters

The waters of this ecosystem spill over the banks of the Orinoco River into one of the largest tracts of seasonally innundated forest in the world and provide important nutrients to the forested floodplains. Migrations of fish and terrestrial animals are timed to coincide with the rising waters that flood large areas of the forest floor. Flooded forests are called "varzea."

Special Features

The Orinoco River is about 1,600 miles (2,600 km) long. It begins in the Sierra Parima highlands, flows north, and creates a large, wide delta just before ending its journey at the Atlantic Ocean. Along its journey the river passes through a diversity of aquatic habitats, including llanos (grassy plains), high-gradient mountain streams, white-sand flooded forests, and large-river environments. The great diversity of habitats has resulted in an extremely high number of locally endemic species.

	Orinoco crocodiles are native to the ecoregion, but some have been seen hundreds of miles further north, as far away as Trinidad. During heavy floods, the crocodiles may be swept out to the Atlantic or carried along on "rafts" of vegetation.

Wild Side

More than 1,000 fish species are estimated to occur in the entire Orinoco basin, the majority of which may be endemic. Among the numerous fish found here are a number of well-known game and aquarium species: peacock bass or speckled pavon, blackspot pirahna, cachama, and red oscar. These waters are also home to the critically endangered Orinoco crocodile and giant river otter, both of which suffer largely from hunting.

Cause for Concern

Many people move to the Orinoco Basin because of its fertile soil. They have cleared large areas of the flooded forests for agriculture and cattle ranching. Trees have also been cut down for timber. Large dams and water diversions are planned for several major tributaries, and these would destroy the water flows that support this ecoregion’s aquatic animals. Pollution and siltation from mining and deforestation, as well as hunting of larger vertebrates, pose additional threats.

Looking Ahead

Check back soon for more about the conservation of this ecoregion.