Reviving the wild U.S. oyster population could help clean up polluted U.S. waterways and support a wide variety of other marine life - but these mollusks need a lot of help from humans.
Students at New York Harbor School, a public academy centered on aquaculture, are among those leading the efforts to rebuild oyster reefs in New York City. These enterprising students showed off the fruits of their labor last Thursday at the New York Academy of Sciences, which hosted a panel discussion called Can Oysters Save New York Harbor?
The short answer to that question, it turns out, is no - but in working to make the harbor more hospitable to oysters, people may end up making a healthier, more sustainable waterway, according to Peter Malinowski, a teacher at the Harbor School.
What can save New York Harbor is if we stop dumping raw sewage in it, Malinowski said. There a lot of natural resources we can't use right now.
Across the country, efforts are underway to repopulate oyster beds that have been ravaged by overfishing and pollution.
Oysters are a keystone species, a term for organisms that have a disproportionately large impact on the ecosystem around them. Oyster beds provide a rich habitat for all kinds of ocean species: mud crabs, grass shrimp, sea anemones and other creatures that attract larger predators like striped bass.
(Another important marine keystone species is the sea otter, which feeds on sea urchins. Without the sea otter, urchins can easily decimate kelp forests -- which support a rich tapestry of aquatic life -- by eating the roots of the kelp plants.)
As an oyster filter-feeds by drawing water through its gills, it traps a lot of particles -- both plankton and pollution. The bits it can't eat are mixed with bunch of mucus, ejected, and settle down to the floor as sediment instead of remaining suspended in the water.
A single adult oyster can process nearly 50 gallons of water a day, according to the Chesapeake Bay Foundation.
The primary ingredient in rebuilding oyster beds is time - it takes between seven to 10 years for a reef to really get going, according to Andrew Jay, president of the Massachusetts Oyster Project, which seeded Boston Harbor with 150,000 oysters in 2008.
Often the hardest hurdle for would-be oyster restoration groups to overcome is red tape.
We've turned down over $50,000 in grant money because we weren't able to get the permitting to spend on projects, Jay said.
State authorities may be leery of new oyster beds because they may present what's called an attractive nuisance. If a passerby - particularly a child -- eats a tainted oyster from Boston Harbor and gets sick, there's a chance they could sue the city or the state on the grounds that they haven't exercised enough caution .
And because of sewage overflows, a common nuisance in most urban harbors, it's likely that any oysters grown in Boston or New York Harbor will be tainted for years to come.
The Harbor School has put out oysters at five sites around New York Harbor, but there are still bureaucratic hurdles to clear: the students need permits to hold the oysters from the state, another permit from the state certifying that their project is consistent with New York's coastal management plan, and another from the Army Corps of Engineers.
The good news is that the climate for oysters may be a bit warmer in New York than in Massachusetts -- Malinowski said New York state authorities were cautiously supportive of the Harbor School's efforts.
In New York, there's so many groups pushing for this -- the National Oceanic and Atmospheric Administration, the Hudson River Foundation, and others, he says -- so they can drive this, politically, MOP's Jay said.
While MOP works to build up its political clout and raise awareness - the organization is putting on screenings of an environmental documentary called Shellshocked - it is also continuing to monitor its oyster population. That original 150,000 is probably down to about 50,000 now, thanks to predators and silt, according to Jay.
If they can make it here ...
New York City is a dangerous place for oysters. If they're not being gulped down with hot sauce at a Coney Island crab shack, they're being whipped into foam and beads by some haute cuisine chef in Midtown.
But the waters around New York City are even more inhospitable to these delectable mollusks, thanks to industrial pollution, parasites, and a sewage system that overflows when the city gets more than a tenth of an inch of rain.
It wasn't always this way - the lower Hudson estuary was once home to 350 square miles of oyster beds. But though New Yorkers have not lost their taste for oysters, the shellfish they're slurping is more likely to come from Massachusetts or Maine instead of the shores of Brooklyn.
Now that the city's waters have cleaned up thanks to years of Clean Water Act regulations, the time may be ripe to seed the lower Hudson and East River with oysters again.
And success in the Big Apple may set a nationwide trend for oyster restoration - the New York effect, according to Paul Greenberg, the author of the book Four Fish: The Future of the Last Wild Food and another NYAS speaker.
Landscape architect and Columbia University assistant professor Kate Orff, another panelist at the NYAS oyster talk, has long been a proponent of oyster-tecture.
With proper design, the idea of city and nature don't have to be in conflict, Orff said at the NYAS discussion.
Encouraging oyster beds is part of a city planning philosophy that gravitates towards softer edges formed by the interaction between natural and manmade structures rather than harder edges sculpted by completely manmade forms.
Restoring New York's oyster reefs is also about a more conscious integration of nature with the city instead of walling it off in a park, according to Greenberg.
We have to get away from the idea that we're going to cordon off this bit of nature and let the rest go to heck, he said.
(Can Oysters Save New York Harbor? is the first of three events in a NYAS series called The Locavore's Dilemma, which explores issues surrounding local food. The next event in the series, The Science Behind the Hype: Resveratrol in Wine & Chocolate, will be held on June 5.)