Watermen claim that dredging helps oyster reefs, creating broader areas of cleaner shell for new oysters to settle on, but most scientists, including Paynter, believe long-term dredging eventually scattered the bars so widely that it interrupted the natural cycles of oyster reproduction.

The Science of Oyster Reefs

When Ken Paynter goes out to work the oyster bars of the Choptank, his boat is a 30-foot Grady White cabin cruiser he calls Crassostrea. It comes equipped with twin outboards, radar, depth finder and GPS, fairly standard gear on this popular sportfishing model. Paynter, however, is not a fisherman by trade or a waterman or a charter boat captain. He's a biologist who studies how to rebuild oyster reefs in the Chesapeake.

Shortly after dawn he meets his two-man crew at a marina at the Route 2 bridge on the South River, several miles below Annapolis. They load the cockpit with wet suits and oxygen tanks for three divers as well as several video cameras, a monitor and VCR.

One of Paynter's key tools, however, is missing. He also used to carry a dark piston, a two-foot long tube called a YSI Data Sonde that can measure water temperature, oxygen, salinity and pH through a whole tidal cycle. A year ago, he scrawled "Ken Paynter" on the tool, clipped it on a line and left it hanging from a buoy above an oyster bar in the Choptank River. When his crew came to retrieve it 24 hours later, the buoy was still there, but their high-tech tool and all their data were gone. The tool had been unhooked, then stolen or deep-sixed to the bottom of the river.

As Paynter fires up the engines, his crew throw off the lines, and the Crassostrea glides down to the mouth of the river where Paynter kicks his twin engines full out. With 500 horsepower firing, they are soon planing and bouncing across the mainstem of the Bay at 40 miles an hour, headed for the Eastern Shore. After a one-hour, bone-rattling ride, the scientists anchor above Beacon's Bar in the Choptank River, the site where they lost their sampling tool.

As the boat swings in the current, two divers squirm into their wet suits, check their camera gear, and buckle on their oxygen tanks. The chief diver is Tim Koles, head assistant for Paynter's lab at the University of Maryland. For the researchers, Beacon's is one of their best sites for monitoring oyster restoration. Replanted with half a million hatchery-spawned baby oysters (spat), it is now an oyster sanctuary, declared off limits to commercial dredging and tonging. With their underwater cameras they are hoping to get video pictures here that will show the public what restoration could do for an undisturbed oyster reef - and what oyster reefs could do for the restoration of the Chesapeake.

A research professor with a joint appointment at the University of Maryland's College Park Campus and its Center for Environmental Science (UMCES), Paynter had been studying oysters for more than a decade when he decided to find out first hand what the historic oyster grounds of the Bay looked like. He signed up for scuba training in swimming pools, but that left him unprepared for the murkiness he often found along the bottom of the Bay, most of it caused by floating phytoplankton and drifting sediment. Some days the water was so dark, "I was mostly diving blind," he says. He learned to feel his way by hand across oyster bars.

On sunny, windless days, however, especially in late fall when the water clears and visibility jumps out to 30 feet or more, Paynter and his divers would get a glimpse of the Bay's fast-approaching future. And it didn't include dredge hauls of even 50 bushels a day for skipjacks under sail. At least not for long.

Most of the reefs he swam across were broken down now, with shells and oysters scattered thinly across the bottom, so thinly that drifting sediments, stirred up by winds and tides, can easily shift over and bury them. Many of the oysters break open in their hands, exposing empty, meatless shells. These are "boxes" caused by the parasites MSX and Dermo which have spread through most of the Bay's oysters over the last four decades.

As they glide across the larger bars, Paynter and his divers can often see the scars left by skipjack dredging. "You'll see a path where a lot of stuff is cleared out," says Koles, "and if you follow that path to where it ends, you'll find a mound of stuff that was pushed up in front of the dredge." Where the dredge has plowed through, the divers find oysters knocked over so they are no longer upright with their bills open, filtering and feeding on plankton in the water. Many oysters end up sideways or upside down with their bills buried in the mud. "Effectively that kills them," says Koles. "It suffocates them."

Once upon a time those bars looked very different. "Oysters formed vast underwater reefs in the Chesapeake Bay," says Paynter, "reefs probably similar to the coral reefs of the Caribbean - providing structure and habitat to hundreds of organisms." These vast assemblages helped clear the water, filtering out phytoplankton at prodigious rates, turning it into shell and meat and energy for reproduction.

Here's what happened to those reefs: overfishing, sedimentation and disease. Heavy fishing, especially in the late 19th and early 20th centuries, began breaking and scattering the ancient reefs. Watermen claim that dredging helps oyster reefs, creating broader areas of cleaner shell for new oysters to settle on, but most scientists, including Paynter, believe long-term dredging eventually scattered the bars so widely that it interrupted the natural cycles of oyster reproduction.

Oyster recruitment requires a critical mass of oysters, larvae and shell. For a good spawn, male and female oysters need to be living in the same place in large numbers and releasing their gametes into the water above the bars at the same time. If a lot of these gametes meet and mix in the waters, there will soon be a lot of new oyster larvae floating and feeding in the water - and looking around for hard places to settle on, places like oyster shells. But all that tonging and dredging had been thinning out the live oysters and scattering the shells needed for spat set.

Overfishing, according to his theory, also exacerbated the effects of sedimentation - especially during the population and construction booms of the last half century. As builders and developers were putting up new buildings and highways and parking lots all around the watershed, they were sending millions of tons a day of loose sediment into all the rivers flowing into the Chesapeake.

All this sediment could easily cover up oysters that were already lying flat and bars that were already broken down, according to Paynter. A fishing boom may have broken down the old oyster reefs - but a population boom helped cover them up.

Why, with all this tonging and dredging, did oyster recruitment last as long as it did?

One answer, according to Paynter, is oyster refuges - secret, unharvested clumps scattered around the Bay. "One could imagine, especially before divers were common, that there were refugia, bits of oyster population that were too deep for tongs or dredges or were secluded on some sort of shelf or shoulder," says Paynter. The Bay is so large that watermen with their antiquated gear simply never found every pocket of oysters that was sitting out there in all those rivers and coves and creeks. From these undiscovered oysters would come strong spawns and then clouds of larvae cast afloat on the currents, ready to create spatfall on harvest bars nearby. Those hidden refuges would once again kick off enough recruitment to sustain a shrinking number of watermen.

Diseases like MSX and Dermo, however, spelled doom for all these obscure oyster grounds, at least in high salinity locations. "When you think about a disease coming in that is spread through the water column," says Paynter, "then you can imagine these pockets of undiscovered oysters being decimated, simply because they breathe the same water." With oysters dying on the hidden bars as well as on the old harvest bars, there is seldom the critical mass needed for large-scale spawning and spat set.

Ken Paynter hands off an underwater video camera to diver Tim Koles. After naming his boat for the oysters he studies, biologist Paynter captured video evidence that oyster reefs, once restored, can create habitat for all kinds of marine life.

Overgrazing of open rangelands, overcutting of
open forests, overhunting of
wild animals, overfishing of the oceans - all these ecological disasters were, according to Hardin's theory, clear examples of the tragedy of the commons.

The Tragedy of the (Oyster) Commons

The drama of the oyster fishery in the Chesapeake was, according to some, an example of the "tragedy of the commons." Since oyster reefs were a common resource - owned by no one, open to everyone - they were, like all commons, doomed to inevitable ruin. The concept of a "tragedy of the commons" came from Garrett Hardin, an ecologist whose 1968 essay in Science magazine made a fundamental contribution to ecology, population theory, economics and political science.

Overgrazing of open rangelands, overcutting of open forests, overhunting of wild animals, overfishing of the oceans - all these ecological disasters were, according to Hardin's theory, clear examples of the tragedy of the commons. As in Greek tragedy, each disaster was both forseeable and inevitable. Everyone could see catastrophe coming and no one could stop it.

Consider oysters in the Chesapeake. Driven by self-interest, the engine of all economic progress in classic capitalist theory, each waterman in the Chesapeake was locked into a competitive race with every other waterman, a race to fish off all the oysters before his neighbor did. The result of the race, according to the classic script, would be overfishing and collapse of the commons.

But the oyster commons belonged to everybody, and it provided more than money for watermen and oyster meat for the rest of us. There's evidence that reefs created habitat for all kinds of animals. And there are theories that the reefs were also great filters for cleaning the Bay's waters, part of a linked system of filters that included seagrasses and wetlands and woodlands. Oysters were a "keystone" species that helped hold up an entire ecosystem. When those filters go out, then turbid water comes in, along with seagrass dieoffs, anoxia and fish kills. Whatever knocks down oyster reefs alters the ecosystem.

While those reefs lasted, however, they also played a role in sustaining the social ecology of the tidewater region. In dozens of waterside towns and on half a dozen small islands, the oyster business was one of the best ways for hard-working men and women to make a good-enough living off the Bay - some from harvesting, others from shucking, packing or shipping. Until the early 1980's, cold-weather oystering was the "keystone" industry for a way of life that, for many, also included fishing and crabbing in the spring and summer and fall. Down at the end of a long neck of flat woodlands and wide-open wetlands, Deal Island, for example, is home to 900 people clustered around three harbors and three villages and at least six Methodist churches, and it was here that Art Daniels was able to raise his sails every winter and through hard work and summer crabbing raise his five children. His three sons all went to work as watermen, and so did some of their children. His skipjack, some days, has three generations of Daniels men on board. All his children still live nearby.

For most of the 20th century, during decades of rural outmigration to the cities, fishing villages like these created habitat for thousands of men and women who carried on the pace and pleasures and traditions of small town life in supportive communities, close-knit by kinship, work ethic and church. Would these Bayside communities break down and thin out like those underwater oyster reefs?

Rebuilding the Reefs

There was, finally, an unexpected plot turn late in this tragedy as ecological crisis finally forced some old adversaries to work together. In the early 1990s watermen, seafood packers, state managers, scientists and environmental organizations began planning joint restoration efforts. With new funding from the federal government, the states of Maryland and Virginia launched an ambitious program to increase the number of new oysters in the Bay by tenfold over the next 10 years. The two states would begin rebuilding the oyster commons.

The idea was breathtaking in scope, hope and hubris, a deus ex machina designed by scientists, a solution that seemed to fire the energies of dozens of organizations and thousands of volunteers. Hatcheries run by the UMCES Horn Point Laboratory and the Department of Natural Resources have been turning out disease-free oyster spat. The Oyster Recovery Partnership, a non-profit corporation, has been organizing ambitious replanting efforts, using volunteers ranging from grade school kids through college students, working professionals and retirees. The Chesapeake Bay Foundation has been recruiting and teaching citizens how to grow out oysters in creekside and Bayside trays and racks.

Planting oysters: Citizens around the Bay have been helping in the effort to restore oysters. Paynter's research shows that restoration could work, at least in the upper, low-salinity reaches of the Chesapeake and its rivers. After two years in the Choptank, his oysters were flourishing.

These programs have proved immensely popular with citizen activists looking for ways to get their hands wet working to help clean up Chesapeake Bay. Raising baby oysters in a back creek and then dumping them overboard on a depleted oyster bar seemed deeply satisfying work for thousands of citizen volunteers. Now that they are nearly gone, oysters - in a typically American turnabout - have also become a cause célèbre.

But is it possible to ever rebuild the Bay's oyster reefs?

Aboard his cabin cruiser Crassostrea anchored over Beacon's Bar in the Choptank River, Ken Paynter gets his crew ready for another dive. He turns on a video monitor that attaches via a long cable to an underwater camera. Koles snaps his goggles twice, clears his mouthpiece and then leans backwards out of the cockpit, somersaulting slowly down into the river. Seconds later, another diver follows.

Within minutes, Koles is gliding towards the oyster bar with a camera and sending video pictures back up to the boat. As he swims closer, his camera shows shell scattered over mud, then a jumbled, jagged pile of replanted oysters. Watching the monitor on the boat, Paynter sees good evidence that oyster restoration might work - at least in small protected plots.

The bar looks jagged because so many of the oysters on top are sticking straight up, with their bills slightly open. According to Paynter, that vertical stance, seldom seen on a harvested bar, is critical to the survival of a living reef. It's hard for drifting sediment to cover over oysters that are erect compared with oysters lying flat on their sides. Upright oysters can filter more food out of the water, and they create more nooks and crannies where other animals can live. Darting among the oysters in the video are small fish, like blennies and gobies and grass shrimp. Clinging to the oysters are mussels and barnacles with their thin little food strainers waving like tiny flags in a liquid wind.

Paynter's team has put a lot of time into trying to capture video like this, a tough trick in water that is so often murky. Tim Koles first pushed the idea, lining up a loaner camera to test. Since then they have experimented with hand-held cameras, cameras dangled off the back of the boat, and remotely operated cameras that they can move around the bottom via a joy-stick control box. Some of the best footage came from stationary cameras they propped up and left on the bottom. When there are no divers around to spy on them, other animals are willing to come out and appear on camera.

Those video clips show lots of animal and plant life clustered around oyster bars. Blue crabs are climbing on the bars and burrowing in the mud; big rockfish are slipping along the reefs, dozens of other fish are swimming through, looking for food. From dozens of dives Paynter has put together highlight reels that are now widely shown to educate the public, lobby legislators for funds and recruit volunteers for work on restoring the great oyster commons. From the clips, it is clear that reefs can be rebuilt and that they can, like the ancient reefs, create filtering power and habitat for fish and crabs.

It is not so clear whether rebuilt reefs can survive disease, but Paynter is finding some hopeful signs. "Many of those oysters, by the way, are still alive and very healthy," says Paynter, pointing at the monitor. They came from disease-free hatchery seed planted on a bottom scraped clean of parasite-infected oysters. After two years in the Choptank, most are flourishing. That's evidence that restoration could work, at least in the upper, low-salinity reaches of the Bay and its rivers.

But Paynter never found out whether the oysters on Beacon's Bar could survive a third year. The next time he fired up Crassostrea and motored across the Bay, he found the bar scraped clean of oysters.

Shortly afterwards, Daniels sent Paynter the funny-looking, piston-shaped tool he had dredged off the bottom of the Bay. Thanks to the good will of a waterman, the scientist got his high-tech tool back a year after it disappeared. But he lost his prize oyster bar.

The waterman lost more. Soon there were newspaper stories about workboats "poaching" on oyster sanctuaries, reports that Daniels, an associate pastor in a Deal Island church, found insulting. Then came investigations by Maryland's Natural Resource Police. There were, however, no buoys marking the sanctuaries, no witnesses to any harvesting and no charges ever filed.

For Daniels the old century ended with controversy - and the new one opened with disaster. In November of 2000, during the first dredge season of the 21st century, his aging skipjack, City of Crisfield, sank at the dock.

Drowned at the dock: in November 2000, Art Daniels' aging skipjack, the City of Crisfield, filled with water, caught a rail, then rolled on its side and sank in the Cambridge harbor.

This page was last modified September 15, 2003

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