A little while ago I wrote about the plight of Amazon river dolphins in the face of dam-building across the region. Here’s the opening few lines, but to read the whole piece please follow the link to the original on Mongabay. A National Geographic photographer kindly let us use some of his pictures, so it is worth a look!
A dam-building boom is underway in the Amazon. More than 400 hydroelectric dams are in operation, being built, or planned for the river’s headwaters and basin. Scientists know that tropical dams disrupt water flow and nutrient deposition, with negative consequences for aquatic animals, especially migratory species. But little detailed knowledge exists as to the impacts of dams on specific species, or as to the best mitigations to prevent harm.
A recent study that tries to fill in that knowledge gap zeroes in on Brazil’s river dolphins. It found that as many as 26 dams could negatively impact dolphin populations and their prey.
The research, led by Dr Claryana Araújo of the Federal University of Goiás, Brazil, focused on two freshwater species: the Amazon River Dolphin, or boto (Inia geoffrensis), which is sometimes famously pink; and the Tucuxi (Sotalia fluviatilis).
The river dolphins of South America are charismatic emblems of rainforest biodiversity, and have captured the public imagination. Swimming in rivers, lagoons, and among submerged tree trunks in flooded forests to chase down prey, they can be found as far inland as the upper reaches of Amazonian tributaries, more than 2,600 kilometers (1,615 miles) from the Atlantic Ocean.