Rio Negro, Amazon

The Rio Negro (in Spanish means "Black River") is the largest left tributary of the Amazon, the largest blackwater river in the world and one of the world's ten largest rivers in average discharge.

It has its sources along the watershed between the Orinoco Flow and the Amazon basins and also connects with the Orinoco by way of the Casiquiare canal in southern Venezuela.

The Rio Negro joins with the Rio Solimpues to form the Amazon River South of Manaus, Brazil.

Rio Negro is navigable for 700 kilometres (430 miles) from its mouth in 1 metre of water in the dry season but it has many sandbanks and minor difficulties. A small portion of it forms the international boundary between Colombia and Venezuela.

In the wet season, it floods the country far and wide, sometimes to a width of 30 kilometres (19 miles) for long distances and for 650 kilometres (400 miles) upstream.

During this time, from April until October, it is a succession of lagoons, full of long islands and intricate channels as far as Santa Isabel to Rio Negro.

While the name Rio Negro means Black River, its waters aren't exactly black; they are similar in colour to strong tea. The dark colour comes from humic acid from incomplete breakdown of phenol-containing vegetation from sandy clearings. The river's name arises from the fact that it looks black from afar.

Much has been written on the productivity of the Rio Negro and other blackwater rivers. The older idea that these are "hunger rivers" is giving way, with new research, to the recognition that the Rio Negro, for example, supports a large fishing industry and has numerous turtle beaches.

Rio Negro has a very high species richness. About 700 fish species have been documented in the river basin and it is estimated that the total is 800-900 fish species, including almost 100 endemics and several undescribed species. Among these are many that are important in the aquarium trade, including the cardinal tetra. And yes, the waters of the Rio Negro are home to piranas !!

A popular full day tour is from the Port of Manaus and to cruise down the Rio Negro to the Meeting of the Waters, the location where the Negro meets the Amazon River. Be awed by this natural phenomenon, where the Negro's black waters and the Amazon's muddy waters flow separately for a few miles. You'll then stop at an ecological park to see the Amazon's famous Victoria regia water plant; have lunch on a floating river restaurant; and take a motorized canoe through the small creeks of the Rio Negro.

Amazon River Cruises operate from October to February. The Equator runs through Ecuador and northern Brazil so much of the continent is tropical. The dry season is from October to June which is when cruises to the Amazon operate.

Language: Spanish (mainly) with some Portuguese and dialects
Currency: US Dollar widely accepted