How The Humble Oyster May Help Save Coastal Cities And Clean Polluted Waters

Mention oysters and the two things that come to mind are slurping them down or wrenching them open for pearls. But now these mollusks may have a bigger role - that of protecting our waterfront cities from rising sea levels and giant storm surges like the one experienced by New York during Hurricane Sandy, and helping clean our increasingly polluted waters.

New York landscape architect Kate Orff and her team at SCAPE studio are the visionaries behind Oyster-Tecture - A man-made park and living reef that they want to create at the mouth of the city's Gowanus Canal an area that was once covered with hundreds of square miles of oysters. Unfortunately they have now more or less disappeared because the edges and ridges that young oysters attach themselves to, were destroyed by underwater dredging that was needed to create shipping routes. What's ironic is that today the canal is known not for its transportation activities, but for being one of the most polluted bodies of water in the United States.

In order to re-introduce the oysters to the canal the team has proposed a design that they call a 'flupsy', or a 'floating upwelling system'. This is essentially a raft with an oyster nursery sunken below the water to allow the oyster eggs to mature to the adolescent phase, where they become known as 'spats.' As they mature from 'spat' to an adult oyster, the shellfish need a place to settle and attach. For that Orff envisions woven nets that will not only provide a comfortable niche for oysters but other kinds of marine life as well, eventually resulting in a living reef. Kate believes that the reefs will act as natural sea-walls, slowing the push of storm waves and rising water, and protecting the city from severe storm damage.

Unfortunately Orff who first proposed this solution almost two years ago, has not met with much success yet, thanks to city regulations that restrict a 'fill' in the harbor. Also, the fact that some recent oyster plantings attempted by the local city departments got destroyed by currents and boat wakes does not help. And then there is the cost - With a bed of million oysters costing about $50,000 USD, and the fact that billions of mollusks would need to be harvested, city officials are a little reluctant to try an experiment that could take at least a decade, to prove successful.

But there is hope that Oyster-Tecture may get its day in the sun. That's because when Mayor Bloomberg recently unveiled his $19.5 billion USD plan to defend New York City against the seas, included in his proposal, was the construction of oyster reefs!

But while officials all over the country may be skeptical about the mollusk's ability to save our coastline, they have no doubt about its other talent - Cleaning up our polluted waters. Using their gills, the oysters efficiently suck up algae, nitrogen, and other pollutants and filter out clean water back into the environment. Experts estimate that each mollusk can clean up to 50 gallons of water a day!

It is therefore not surprising that there is currently a nationwide movement to try to restore this once abundant bivalve. Maryland has already succeeded in re-establishing one of the largest oyster sanctuaries in the world and a project is also underway in Chesapeake Bay where a combination of over-fishing, pollution and disease, has devastated the population of oysters in an area that Native Americans once called Shellfish Bay. Earlier this year, Federal and state agencies set aside $30 million USD to try restore the mollusks, improve the water quality, as well as stabilize the shorelines of the 3,200 square-mile estuary. Some of this money has already been put to use with the harvesting of two billion baby oysters in Harry Creek, a narrow tributary of the Choptank River, Delaware.

While it will take years before the experts really know if the creek's oysters can sustain themselves and thrive again, naturalists are hopeful. That's because if successful it may inspire similar projects throughout the world, which will not only help us, but also, sea life and migratory birds that have been using oyster reefs as habitats for years! Who knew that the humble oyster was so important to our well being?

Resources: livescience.com,animalnewyork.com,tedtalks.com, sfgate.com, theatlanticcities.com