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The Declining Status of Freshwater Biodiversity and National and International Water Resources
| Resources: Global Water Issues |
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Books and Articles: World Resources Institute: EarthTrends Choose from the menu associated with 'Water Resources and Freshwater Ecosystems.' |
Worldwide, most types of freshwater ecosystems generally are in grave condition and are declining at a much faster rate than terrestrial systems. Consider some of the evidence:
More than 20 percent of the world’s known 10,000 freshwater fish species have become extinct or imperiled in recent decades. In the United States, 303 fish species, or 37 percent of the freshwater fish fauna, are at risk of extinction; 17 species have already gone extinct, mostly in this century. More than two-thirds of U.S. freshwater mussel species are vulnerable to extinction or are already extinct. Imperilment rates are disproportionately higher than those for terrestrial plants and animals.
Half of the world’s wetlands are estimated to have been lost during the 20th century, with more than half having already been destroyed in the United States.
Historical trends in commercial fisheries data for major rivers of the world show dramatic declines during the 20th century.
