2018-马达加斯加和印度洋岛屿热点地区淡水生物多样性现状及分布（英文版）-10mb

Summary of the Status and Distribution of Freshwater Biodiversity in Madagascar and the Indian Ocean Islands Hotspot

Core Content

This report provides a comprehensive assessment of the status and distribution of freshwater biodiversity in Madagascar and the Indian Ocean Islands hotspot. It highlights the high levels of endemism and biodiversity within the region's inland waters and identifies key threats and conservation priorities.

Main Points

Freshwater Biodiversity in the Hotspot

• The hotspot includes Madagascar and its neighboring islands: Mauritius, the Comoros, Seychelles, La Réunion, Mayotte, and the Scattered Islands of the Western Indian Ocean.
• It is home to a rich array of freshwater species including fishes, molluscs, decapods, odonates, and aquatic plants.
• Freshwater ecosystems support both direct (e.g., fisheries) and indirect (e.g., water purification) benefits for local communities and economies.

Threats to Freshwater Species

• Habitat loss and degradation are the primary threats, driven by unsustainable agricultural practices such as slash and burn and wetland drainage for rice cultivation.
• Overuse of natural resources by local communities, including deforestation and over-fishing, contributes significantly to the decline of freshwater biodiversity.
• Hydropower development is altering hydrological regimes and affecting connectivity and ecosystem health.
• Mining activities pose growing threats, especially in areas like Fort Dauphin and the eastern region.
• Invasive alien species impact native biodiversity through predation and resource competition.
• Climate change exacerbates these threats, leading to more frequent and severe environmental stressors.

Conservation Status

• A total of 653 species were assessed against IUCN Red List Categories and Criteria, representing the most comprehensive freshwater biodiversity assessment in the hotspot.
• 43% of all assessed species are threatened with extinction, assuming all Data Deficient species are equally at risk.
• 23% of species are classified as Data Deficient due to insufficient information, highlighting the need for further research and monitoring.

Key Biodiversity Areas (KBAs)

• 23 freshwater KBAs were identified and confirmed by experts, supporting 80 globally threatened and 62 geographically restricted range species.
• 10 of these KBAs also meet the criteria for Alliance for Zero Extinction (AZE) sites.
• These KBAs are crucial for protecting freshwater biodiversity and should be prioritized in conservation planning.

Conservation Recommendations

• Integrated River Basin Management (IRBM) and Environmental Flows should be implemented to maintain water quality, quantity, and flow timing.
• Site protection is essential, especially in areas with high biodiversity value.
• Environmental Impact Assessments (EIAs) must include reference to the IUCN Red List data sets.
• Collaborative field research and monitoring are needed to address data gaps and improve conservation efforts.
• Capacity building within government bodies is vital for better enforcement of environmental laws and sustainable resource management.
• Community involvement and stakeholder engagement are critical for the long-term success of conservation initiatives.

Key Information

Project Overview

• The project was led by the IUCN Freshwater Biodiversity Unit in collaboration with the Missouri Botanical Garden – Madagascar.
• It was funded by the Critical Ecosystems Partnership Fund and supported by various international and national partners.
• The report includes detailed Red List assessments, species distribution maps, and recommendations for conservation and policy.

Policy Relevance

• The findings support the implementation of Multilateral Environmental Agreements such as the Ramsar Convention and the Convention on Biological Diversity.
• It aids in achieving UN Sustainable Development Goals (SDGs), particularly:
  • SDG 6.6: Protect and restore water-related ecosystems.
  • SDG 6.5: Implement integrated water resources management.
  • SDG 15.1: Conserve, restore, and sustainably use terrestrial and inland freshwater ecosystems.
  • SDG 15.5: Reduce habitat degradation, halt biodiversity loss, and protect threatened species by 2020.

Data and Resources

• The full dataset, including species distribution maps, is available on a DVD and through the IUCN Red List website.
• KBA boundary maps will soon be accessible online via the World Database for Key Biodiversity Areas.

Conclusion

Madagascar and the Indian Ocean Islands hotspot are home to a vast and unique freshwater biodiversity. However, this biodiversity is under severe threat due to human activities and climate change. The report emphasizes the importance of integrating freshwater biodiversity into conservation and development planning, enhancing data collection, and involving local communities and stakeholders in sustainable management practices. The identified Key Biodiversity Areas and conservation strategies provide a roadmap for protecting these ecosystems and the species they support.