(February 3, 2011) Those familiar with Chesapeake Bay know that its once-vast oyster population stands at a tiny fraction of its historical abundance. A new study by an international team including professor Mark Luckenbach of the Virginia Institute of Marine Science shows that the decline of oyster reefs is not just a local problem.
The team's global comparison of oyster reefs past and present shows that oyster reefs are at less than 10% of their prior abundance in 70% of the 144 bays studied, ranging from China to England to Australia to Brazil. Overall, they estimate that 85% of Earth's oyster reefs have been lost, typically due to overharvesting, habitat degradation, and disease.
The researchers note that the scope of oyster loss exceeds that for any other shallow-water marine habitats that have been similarly studied. "The most striking thing about our analysis," says Luckenbach, "is that it shows that oyster reefs are the most threatened of all shallow-water, structured habitatsmore so than coral reefs, mangroves, or wetlands."
Luckenbach and his co-authorswho hail from California, China, Florida, Italy, New Jersey, Rhode Island, Tasmania, Uruguay, and Washington, D.C.hope the results of the their study will help overcome what they see as one of the most pervasive obstacles to successful management of oyster reefs: "the perception among managers and stakeholders that no major problems exist."
In addition to quantifying oyster-reef loss, the study also shows that recovery is possible, and suggests several management approaches that can aid restoration of oyster populations and the economic and ecological services they provide. Oysters filter water; offer food and habitat to fish, crabs, and birds; stabilize the shoreline; and have traditionally supported commercial fisheries.
The authors note that many of the countries in which oyster reefs remain most abundant have comparatively strong mari
|Contact: David Malmquist|
Virginia Institute of Marine Science