The Nature Conservancy. Protecting nature. Preserving life.™

The Shellfish Reefs at Risk report provides the first global view of the distribution and condition of oyster reefs – one of the most important and valuable resources for humans but among the least well recognized as a habitat.

Compiling published data as well as expert surveys and direct observations, the report provides condition estimates for oyster reefs in more than 144 estuaries in 44 ecoregions around the world. The report concludes that shellfish reefs are the most imperiled marine habitat on earth.

Shellfish reefs and beds are essential to the health of marine ecosystems, yet they are almost always solely managed as fisheries. There are many obstacles to successful management, but the greatest include the perceptions that a problem does not exist or that it a local problem only and that non-native shellfish can replace wild native species. These problems are exacerbated because of bay by bay management that does not recognize regional, national or global problems and solutions. Native oysters must be recognized for the reef habitat that they provide across bays, regions and globally.

A major shift in management is needed to conserve and restore shellfish habitats to return a full array of critical ecosystem services to people and nature. Realistic and cost-effective solutions in conservation, restoration and management can help turn the tide for shellfish reefs. By implementing these solutions, we can work to stem reef loss and increase the viability of this critical habitat.

Oyster reefs by the numbers:

• Globally 85 percent of oyster reefs have been completely lost.
• In most bays and ecoregions, shellfish reefs are at less than 10 percent of prior abundance.
• Reefs are functionally extinct in many areas, particularly in North America, Australia and Europe.
• Most of the world’s remaining wild capture of shellfish comes from only five ecoregions (of 152 with reported catch) on the east coast of North America and the reefs in these regions are in poor condition or worse
• Only 10 ecoregions in the world presently report wild capture rates above 1000 tonnes, down from millions of tones 50-100 years ago.
• There are a few places with opportunities for conservation on each continent.