Nearly a quarter of freshwater animals face extinction, a new study reveals. The research, published in Nature, highlights the interconnected threats to these ecosystems and their inhabitants.
Freshwater environments, though covering a tiny fraction of Earth's surface, are vital to a significant portion of global biodiversity. They support 10% of all animal species, but are incredibly fragile. "Huge rivers like the Amazon can appear mighty, but at the same time freshwater environments are very fragile," notes study co-author Patricia Charvet.
The study analyzed over 23,500 species of freshwater animals, finding a critical risk to 24% of them. These risks stem from a variety of interconnected factors including pollution, dam construction, water extraction, agriculture, invasive species, and climate change. "Most species don't have just one threat, but many threats acting together," explains co-author Catherine Sayer.
This research marks a significant advance, being the first global analysis of freshwater species' extinction risk. Previous studies primarily focused on terrestrial animals. "This is a long-awaited and hugely important paper," comments Duke University ecologist Stuart Pimm, who wasn't involved in the study. He noted the substantial modification of many major rivers, particularly in North America and Europe, driven by damming.
The Amazon Basin, a crucial freshwater ecosystem, is particularly vulnerable. Deforestation, wildfires, and illegal gold mining, according to Charvet, introduce pollution and toxins into the water system. "Rivers and wetlands concentrate everything that happens around them. If something goes wrong, like a spill, an entire species can be threatened," she warned.
This study underscores the urgent need for conservation efforts to protect these crucial, yet often overlooked, ecosystems.
