David Schulte, a marine biologist with the U.S. Army Corps of Engineers, is trying to engineer a recovery for Chesapeake Bay oysters. He has developed a small reef area to provide a habitat for oysters in one of the bay's tributaries.
David Schulte, a marine biologist with the U.S. Army Corps of Engineers, is trying to engineer a recovery for Chesapeake Bay oysters. He has developed a small reef area to provide a habitat for oysters in one of the bay's tributaries. Elizabeth Shogren/NPR
Chesapeake oysters are a succulent treat that for centuries have been loved almost to extinction. But some scientists and business people are making headway in bringing back the bivalve, for the sake of oyster lovers and the bay.
A successful restoration project, a report showing that fewer oysters are dying from disease, and the growth of oyster farming all give cause for optimism. Still, experts caution that Chesapeake oysters have a long way to go. Overfishing, disease and pollution have left the bay with only about 1 percent of the oysters it once had.
President Obama has pledged to make good on decades-old promises to restore the Chesapeake, the nation's largest estuary, and scientists and environmental activists say he needs oysters to help him do that.
"We're not going to restore the Chesapeake Bay without oysters. It's one of the most important cleaners of the bay that we have," says Tommy Leggett, who manages oyster restoration in Virginia for the environmental group Chesapeake Bay Foundation. Oysters are valuable to the bay because they eat lots of algae. Without them, the bay is like a fish tank without a filter.
Scientists estimate that there used to be so many oysters in the Chesapeake that they could filter the whole bay in several days. Now it takes the few oysters that are left about a year to do the same job.
Tommy Leggett, an oyster farmer and manager of oyster restoration for the Chesapeake Bay Foundation in Virginia, says large restoration projects are worth the high price tag because they can withstand the threats of disease, predators and muck that have doomed smaller projects.
A Reef Restoration Project
Marine biologist David Schulte has been trying to engineer a recovery for the bay's oysters, starting with one of its small tributaries, Virginia's Great Wicomico River.
Schulte, who works for the U.S. Army Corps of Engineers, explains how he dumped a huge number of old oyster shells into the river and created a large new reef system. To check on his reefs, he sends a remote-controlled underwater submarine that looks like a lime green canister vacuum cleaner overboard.
Schulte's theory was if you build it — and build it big enough — they will come. And for the past several years, wild baby oysters have been coming by the millions to his reefs.
"That's a great shot right there," Schulte says as he peers at a screen and sees lots of craggy shells standing on end in the murky brown water. "Those oysters are all growing very vertically, very densely packed together. This was the first time this was documented in the Chesapeake Bay in over a century."
Schulte counted 1,000 oysters per square meter. That's what nature used to provide, but no one had been able to mimic it before. This restoration project is working where many others failed because he came up with a radically new recipe, Schulte says.
After studying successful restoration projects in other parts of the world, he decided that he had to build a reef much larger than earlier efforts. Instead of 1 acre, his was 100 acres. And after reading historic accounts of what oyster reefs once looked like, he decided his reefs had to be higher. So he piled up enough shells to stick up a foot or more from the river bottom instead of a few inches. He hoped that would prevent the oysters from being smothered by the muck, as in previous experiments.
"It turns out from all the data we've got, I was right," says Schulte. He argues that his experiment should be scaled up across the bay, but many other scientists are skeptical.
An Expensive Undertaking
One big concern is expense. Schulte's project cost $3 million, and similar projects in the bay's big tributaries would cost many times that much.
"Once you get into trying to do restoration in very large rivers, the quantities of shell that would be needed, and the dollars that are involved in it get to be extraordinary," says professor Roger Mann of the Virginia Institute of Marine Science. "And before you start spending those amounts, you need to be absolutely sure that the recipe you're using is right."
Mann believes the best way to bring back oysters is to promote a new industry on the Chesapeake — oyster farming. That way, businesses — not taxpayers — will be footing the bill to put millions of the filter feeders back in the bay.
Scientists say oyster farms offer a lot of the same ecological benefits that come from wild oyster reefs. They filter water and provide habitat for fish, crabs and other creatures.
"There are a lot of very clever people in this industry who are willing to work hard to build their oyster farms and in doing so can have really positive ecological effects," Mann says.
A New, Nondestructive Oyster Harvest
One such person is Ryan Croxton, who started farming oysters with a cousin several years ago on Virginia's Rappahannock River. His grandfather used to supply oysters to Campbell's Soup, but no one had harvested for many years, and the family was about lose leases it had to work the river.
Ryan Croxton's grandfather's oyster operation dragged dredges across oyster reefs, ripping up the habitat. Croxton grows oysters in cages for the half-shell market.
Ryan Croxton's grandfather's oyster operation dragged dredges across oyster reefs, ripping up the habitat. Croxton grows oysters in cages for the half-shell market. Elizabeth Shogren/NPR
"We wanted to keep the lease alive. It had been in our families since the 1890s," Croxton says. "And that's when we realized there was a disconnect between the way we were doing it and the way we ought to be doing it."
His grandfather's teams dragged big dredges across the bottom of the river, ripping up the habitat as they went. The Croxtons now grow oysters in cages.
They started the farm so they could have a private stash, but they loved the product so much that they decided to aim big. So they consulted a restaurant guide to decide where to make their first pitch.
"So we got a Zagat Guide and looked at the No. 1 restaurant in New York City, which is Le Bernardin, and just called the reservation line," Croxton recalls. "It's easy to be bold when you've got nothing to lose. And were able to get an audience with the chef and showed him the oyster. He absolutely loved it."
Now they sell 30,000 to 40,000 oysters a week for the half-shell market.
Croxton is reluctant to criticize his grandfather. "That's my blood, so I've got to be careful. But I do feel bad about the techniques that they used. We've completely abandoned all of them," he says.
Instead of tearing down the bay like his predecessors, he hopes his operation is helping revive it. As he surveys a line of oyster cages on the choppy river, Croxton says there's no question that the hundreds of thousands of oysters below help remove pollution.
"Each one of these oysters is filtering like 50 to 60 gallons a day," he says.
An Oyster Comeback?
Environmental activists agree that oyster farms can do some good, but not on the scale needed to help rescue the bay.
Oyster farmer Leggett has become a believer in big-scale restoration projects, like the one in the Great Wicomico, thanks to what he's seen happen in the mini-version that he built in a tiny creek. He says he had hoped some wild baby oysters would settle on the mound of shells he dumped into the creek, and he's been thrilled by how many healthy, mature oysters have made this their home.
He jumps into the water to grab some evidence of his success and pulls out three wild oysters, one of them 3 inches long.
Large restoration projects will be less likely to succumb, as many small ones have, to threats like sediment, predators and disease, he says. And Leggett says now is a good time to make hefty public investments in rescuing oysters. His group recently came out with a report documenting that fewer oysters are dying from two diseases that have long plagued them. If oysters are developing resistance to disease, he argues, that's one more reason to believe that staging an oyster comeback will be worth its big price tag.