World's freshwater species facing extinction, 25% under extreme threat

With almost 90 species already declared extinct, the urgency for action is clear.

In Short

• IUCN evaluated 23,496 species, including fish, crustaceans
• The findings show the urgent need for conservation efforts
• Almost 90 species have been already declared extinct

A recent study published in the journal Nature reveals a troubling statistic: nearly 25% of the world's freshwater species are at risk of extinction.

This assessment, conducted by the International Union for Conservation of Nature (IUCN), evaluated 23,496 species, including fish, crustaceans like crabs and shrimp, and insects such as dragonflies and damselflies. The findings show the urgent need for conservation efforts in these vital ecosystems.

Lead author Catherine Sayer, who heads the IUCN's freshwater biodiversity unit, highlighted that 24% of these species face high extinction risks due to several prevalent threats.

"Pollution, dams, water extraction, agriculture, and invasive species are major contributors," Sayer noted. Alarmingly, 30% of crustaceans are threatened, followed by 26% of fish and 16% of odonates.

Among the species identified as critically endangered are the mini blue bee shrimp from Sulawesi and the Atlantic helicopter damselfly from Brazil. These creatures inhabit various freshwater environments such as lakes, rivers, and wetlands—areas that have seen a reduction of more than one-third since 1970.

The study also pinpointed regions with significant biodiversity loss. Lake Victoria in Africa and Lake Titicaca in South America were highlighted as hotspots for threatened species. Both lakes face similar threats from pollution and overfishing, particularly from invasive species like the Nile perch.

Ian Harrison, a co-author and freshwater conservationist at Northern Arizona University, emphasized the ecological importance of these habitats. "Freshwater ecosystems support diverse species that provide essential services such as carbon sequestration and food resources," he stated.

With almost 90 species already declared extinct, the urgency for action is clear. The researchers advocate for integrated water resource management strategies that prioritize ecosystem health while addressing human water needs.

"This study serves as a baseline for tracking progress in conservation efforts," Harrison concluded, calling for immediate action to mitigate further declines in freshwater biodiversity.