Oysters May be Able to Protect Us from Rising Seas

Scientists discovered that oyster reefs grow rapidly enough to match sea level rise, and may be able to keep future flooding at bay, according to research published in the journal Nature Climate Change.

Oyster colonies provide habitat for wildlife, filter muck out of waterways, stabilize and raise shorelines, and can withstand the impact of storm surges, helping to spare lowlands from flooding.

That all sounds great, if it weren't for the fact that 85 percent of the oyster reefs that once dominated the bays and estuaries of the world have disappeared. Overharvesting is mostly to blame, but so is shoreline development and pollution, authors note.

Oysters love to reside in intertidal areas - the portions of shoreline that are exposed during low tides and inundated when tides are high - to seek refuge from predation, competition and disease. With rising sea levels threatening these sanctuaries, scientists question whether oysters can quickly adapt.

The good news is oyster reefs can flourish incredibly fast. The findings suggest that oyster-reef restoration projects could reduce flooding as global warming heightens seas.

"We could construct intertidal reefs near shorelines that provide fish habitat, clean the water, keep up with sea-level rise, and protect the shoreline by buffering erosion and promoting sedimentation," Antonio Rodriguez, a University of North Carolina associate professor who was involved with the study, told the Pacific Standard. "That would be a huge improvement over any artificial shoreline stabilization method."

Scientists took reef samples from a North Carolina research reserve and used laser scanners to gauge the growth rates of those reefs.

The scientists wrote in their paper that the reefs could double in volume every four years, growing "rapidly in all directions," suggesting that "intertidal reefs have the potential to match even the highest predictions" of sea-level rise forecast by 2100.

But, growing these reefs along shorelines still has its challenges. Authors add that the next step is learning how and where to grow reefs along estuary shorelines as quickly as possible.