Freshwater Species Face Threat of Extinction

Recent research has revealed alarming statistics regarding the status of freshwater species worldwide. A multi-taxon global assessment, conducted for the International Union for Conservation of Nature (IUCN) Red List, indicates that nearly 25 per cent of the 23,496 studied species of decapod crustaceans, fishes, and odonates are at risk of extinction. This assessment, published in January 2025, marks the urgent need for conservation efforts.

Extent of Threatened Species

Out of 23,496 freshwater species, 4,294 are classified as threatened. This includes 89 confirmed extinctions and 178 suspected extinctions since 1500. The regions with the highest number of threatened species include Lake Victoria, Lake Titicaca, Sri Lanka’s wet zone, and India’s Western Ghats. These areas are biodiversity hotspots, hosting many endemic species.

Primary Threats to Freshwater Biodiversity

The study identifies several key threats contributing to the decline of freshwater species. Agriculture and invasive species are threats. Additionally, pollution, dam construction, and water extraction pose severe risks. Overharvesting is also a major concern. The study stresses that these threats require comprehensive management strategies at a catchment scale.

Impact of Climate Change

Climate change is important factor affecting freshwater ecosystems. It alters temperature and flow regimes and increases the frequency of severe weather events. This not only directly impacts species but also exacerbates existing threats, such as invasive species and heightened human demand for water resources.

Conservation Priorities

The IUCN report puts stress on the importance of integrating conservation efforts for both freshwater species and tetrapods. Areas with overlapping conservation priorities should ensure that both groups are included in management plans. Addressing the distinct needs of freshwater species is essential for effective conservation.

Importance of Freshwater Ecosystems

Freshwater ecosystems support over 10 per cent of all known species, including proportion of vertebrates and fishes. They provide vital ecosystem services such as nutrient cycling, flood control, and climate change mitigation. Protecting these ecosystems is crucial for both biodiversity and human well-being.

Call to Action

Catherine A Sayer, IUCN’s Freshwater Biodiversity lead, has emphasised the need for immediate action. The lack of data on freshwater biodiversity can no longer justify inaction. Freshwater landscapes are essential for safe drinking water and livelihoods for billions of people. Protecting these areas is imperative for both nature and humanity.

Upcoming Conservation Initiatives

The 2025 IUCN World Conservation Congress, scheduled for October in Abu Dhabi, aims to guide global conservation efforts. It will focus on achieving sustainable development goals and the Kunming-Montreal Global Biodiversity Framework targets by 2030. This congress represents a critical opportunity to address the challenges facing freshwater biodiversity.

Questions for UPSC:

1. Discuss the impact of climate change on freshwater ecosystems and species.
2. Critically examine the role of agriculture and invasive species in the decline of freshwater biodiversity.
3. Explain the significance of freshwater ecosystems in supporting global biodiversity and human livelihoods.
4. With suitable examples, discuss the relationship between freshwater species conservation and overall ecosystem health.

Answer Hints:

1. Discuss the impact of climate change on freshwater ecosystems and species.

1. Climate change alters temperature and flow regimes, affecting species survival.
2. Increased frequency of severe weather events disrupts freshwater habitats.
3. Climate change amplifies existing threats like invasive species and pollution.
4. Changes in hydrology can lead to habitat loss and fragmentation.
5. Long-term impacts may include shifts in species distributions and biodiversity loss.

2. Critically examine the role of agriculture and invasive species in the decline of freshwater biodiversity.

1. Agricultural runoff introduces pollutants, leading to water quality degradation.
2. Invasive species outcompete native species for resources, disrupting ecosystems.
3. Land conversion for agriculture reduces natural habitats for freshwater species.
4. Both factors contribute to habitat alteration and loss of biodiversity.
5. Integrated management practices are needed to mitigate these impacts.

3. Explain the significance of freshwater ecosystems in supporting global biodiversity and human livelihoods.

1. Freshwater ecosystems host over 10% of all known species, including many vertebrates.
2. They provide essential services like nutrient cycling and flood control.
3. Freshwater resources are critical for drinking water and agriculture, supporting billions.
4. Healthy ecosystems contribute to climate change mitigation efforts.
5. Loss of freshwater biodiversity threatens both ecological balance and human well-being.

4. With suitable examples, discuss the relationship between freshwater species conservation and overall ecosystem health.

1. Healthy fish populations indicate a balanced aquatic ecosystem (e.g., Lake Victoria).
2. Conserving endemic species helps maintain local biodiversity (e.g., Sri Lanka’s wet zone).
3. Freshwater plants contribute to water filtration and habitat stability.
4. Declines in freshwater species can signal broader environmental issues (e.g., pollution).
5. Integrated conservation efforts promote resilience in ecosystems, benefiting all species.