- Species Red List Assessments
- Key Biodiversity Areas (KBAs)
- Wetland Assessments
Past Red List assessments of freshwater taxa have rarely been conducted on a comprehensive basis so it is difficult to provide a reliable estimate for their global levels of threat. However, the FBU and its partners have now completed several comprehensive regional assessments and the initial results are very worrying. For example, 54% of Madagascar’s native freshwater fish species are threatened. In Eastern Africa 54% of freshwater crabs and 16% of the molluscs are threatened, as are 56% of freshwater fishes endemic to the Mediterranean basin. The SSC's Global Amphibian Assessment also reports high levels of threat with 32% of amphibians assessed as globally threatened and a further 23% as Data Deficient. The freshwater mussels are perhaps the best known of freshwater molluscs and their status is well known for North American populations of which 35% of the 297 taxa are listed as Extinct, Endangered, or are candidates for listing as Endangered.
Future work aims apply the comprehensive assessment approach that we have developed on a global scale. We work closely with the IUCN Centre for Mediterranean Cooperation in undertaking regional assessments of freshwater species within the Mediterranean basin which have revealed high levels of threat for some species.
The major threats to freshwater biodiversity include habitat loss, introduction of alien species, pollution, and over-harvesting. There are many examples to illustrate the severity of the situation:
The Freshwater Biodiversity Unit is conducting regional assessments of the status and distribution of a number of priority groups of freshwater taxa.