Instant Insight

30-Second Take

• About a quarter of the world’s freshwater animals are at risk of extinction.
• Threats include pollution, dams, water extraction, agriculture, invasive species, and climate change.
• Freshwater ecosystems support 10% of the planet’s animal species despite covering less than 1% of its surface.

Quick Brief

2-Minute Digest

Essential Context

New research published in the journal Nature reveals that nearly a quarter of the world’s freshwater animals are threatened with extinction. This alarming figure is based on an analysis of over 23,500 species, including fish, decapod crustaceans like crabs and shrimps, and odonates such as dragonflies and damselflies.

Core Players

• Catherine Sayer – Lead of the freshwater biodiversity team, International Union for Conservation of Nature (IUCN)
• Patricia Charvet – Biologist, Brazil’s Federal University of Ceará
• International Union for Conservation of Nature (IUCN) – Global authority on the conservation status of species
• Stuart Pimm – Ecologist, Duke University

Key Numbers

• 24% – Percentage of freshwater species at risk of extinction
• 10% – Proportion of the planet’s animal species supported by freshwater ecosystems
• 1% – Percentage of the planet’s surface covered by freshwater habitats
• 23,500 – Number of freshwater species analyzed in the study
• 54% – Percentage of studied species affected by pollution
• 39% – Percentage of studied species impacted by dams and water extraction

Full Depth

Complete Coverage

The Catalyst

“Most species don’t have just one threat putting them at risk of extinction, but many threats acting together,” said Catherine Sayer, highlighting the compounding effects of various threats on freshwater species.

This comprehensive study marks the first global assessment of the extinction risk faced by freshwater animals.

Inside Forces

Freshwater habitats, despite their small coverage, are highly fragile and support a significant portion of global biodiversity. “Huge rivers like the Amazon can appear mighty, but at the same time freshwater environments are very fragile,” noted Patricia Charvet.

The study underscores the critical role of these ecosystems in providing benefits such as nutrient cycling, flood control, and climate change mitigation.

Power Dynamics

The IUCN’s findings have significant implications for conservation efforts and policy-making. Stuart Pimm, a Duke University ecologist, described the study as “a long-awaited and hugely important paper.”

The engagement of global authorities and local communities is crucial in addressing the multifaceted threats to freshwater species.

Outside Impact

The broader implications of this research are substantial. Climate change, for instance, is expected to intensify its impact on freshwater species in the future, making habitats more susceptible to invasive species and altering ecological balances.

Human activities such as deforestation, agriculture, and damming also play a critical role in threatening these species. For example, in South America, the Amazon River ecosystem faces threats from deforestation, wildfires, and illegal gold mining.

Future Forces

Looking ahead, addressing these threats will require concerted efforts from governments, conservation organizations, and local communities. “We have about a quarter of species which are on their way to extinction if we don’t do anything to stop it,” warned Sayer.

Key areas for future action include regulating pollution, managing water resources sustainably, controlling invasive species, and mitigating the impacts of climate change.

Data Points

• 90 – Number of freshwater species already reported extinct.
• 30% – Percentage of decapod crustaceans threatened with extinction.
• 26% – Percentage of freshwater fish threatened with extinction.
• 16% – Percentage of odonates threatened with extinction.
• 18% – Percentage of freshwater species threatened by climate change.