OuiSi - Logo - Blk
Aquatic Vegetation in the Amazon Forest


Rio Negro, Anavilhanas National Park, Novo Airão, Amazonas, Brazil




The Anavilhanas National Park is a Brazilian conservation unit created to protect the Anavilhanas Archipelago and its biodiversity. Located in the Rio Negro basin, this is the second largest river archipelago in the world, with around 400 islands and lakes, and is home to endangered species such as the Amazon river dolphin (Inia geoffrensis), the tucuxi dolphin (Sotalia fluviatilis) and the Amazonian manatee (Trichechus inunguis). Rio Negro is the largest blackwater river in the world and has this color because its waters are dyed by humic acid, released by the submerged foliage of the trees. Running slowly, the river has high acidity which reduces the proliferation of mosquitoes.

Photo Link

Learn More

Inae Guion
Biologist, Researcher, Visual Storyteller
Learn more about Inae Guion.

Explore more with OuiSi Nature

OuiSi Nature: 75 – Caribbean Flamingo – Tania Escobar
OuiSi Nature: 4 – Bat-eared Fox – Melissa Groo
OuiSi Nature: 97 – Male Bonobo – Christian Ziegler
OuiSi Nature: 162 – Emerald Longhorn Beetle – Joseph Saunders
OuiSi Nature: 131 – Manica Sugarbush – Jen Guyton
OuiSi Nature: 100 – Nurse Shark – Inka Cresswell