Getting back the wild oyster
“In the 1960s, there were a thousand bushels of oysters out here,’’ said Bob Prescott, director of Mass Audubon’s Wellfleet Bay Wildlife Sanctuary. He spreads his arms wide and turns.
We are standing on sand flats off the western edge of Lieutenant Island in Wellfleet Bay, and I’m trying hard to imagine such a thing. I see sand in every direction, an undulating toast-colored landscape punctuated by shimmery pools of tidal water reflecting the periwinkle sky.
A dozen of us cluster around Prescott. We are on an Oyster Reef Tour, hoping to learn about the history of wild oysters on the Outer Cape and to observe the reef restoration experiments launched in 2009 by Mass Audubon, The Nature Conservancy, and the National Oceanic and Atmospheric Administration. The project aims to restore a section of an oyster reef that once extended from Boston through New York down into Chesapeake Bay. (The famous Wellfleet oysters of today are farmed on grants in other parts of the bay.)
“The oyster habitat is gone,’’ said Prescott. “There hasn’t been a [stable] oyster reef in Wellfleet since 1770. It was fished out by early harvesters.’’
A compact man with a curly rim of white hair poking out from beneath his baseball cap, Prescott has seemingly boundless energy. Like a true scientist, he poses more questions than he can answer, a fact that does not seem to bother him at all.
“An oyster reef is a massive structure of living organisms, the ecological equivalent of coral reefs,’’ he said. “How do we rebuild it? This is a giant scientific experiment to get us to the point where we can restore habitat.’’
The oysters here in the 1960s were dispersed as strong tides, shifting sands, and prevailing winds changed the landscape. Without a reef, there was nothing to hold the oysters in place.
“It’s a dilemma,’’ Prescott said. “How do you put oysters back in an area where the sand is moving? This is the most challenging aspect of creating a stable reef. How do you put a foundation under a reef? What do you use for substrate?’’
The enormous tidal flow in Wellfleet Bay is part of what makes its oysters so tasty, but it is also problematic for establishing a wild reef. In a mere six hours the sand on which we are standing will be under 10 feet of water.
We traipse across the flats in knee-high boots or sturdy sneakers, attempting to keep up with Prescott, who offers a running commentary on life on this spit of land. What I saw as only sand in fact teems with life. There are horseshoe crab tracks, fiddler crabs, mud snails (“the scavenger of the salt marsh’’), glassy tube worms, a smattering of oysters, razor clams, and the egg masses of lug worms, long gelatinous forms that look like jellyfish.
Prescott lifts his binoculars and points to a small brown animal skittering across the sand. “I’ve never seen a chipmunk out here before!’’
When the scientist leading a tour is excited and surprised by the habitat, the enthusiasm is infectious. We are like 10-year-olds in awe of our surroundings. We have come to learn about oysters, and we do.
The sanctuary, which owns 243 acres of these flats, is experimenting with a series of structures where oyster seeds can attach themselves and thrive. In order to grow, a wild infant oyster needs to attach to a hard surface, such as a rock or a larger shell. Working closely with Massachusetts Department of Fish and Game’s Division of Marine and Fisheries and the Town of Wellfleet, the Mass Audubon staff is utilizing bare concrete balls, concrete blocks, netted mesh bags filled with more shells, and mounds of surf clam shells called cultch, or what Prescott describes as “shell mulch,’’ to discover what will best form a reef structure.
After monitoring the structures for the past two years, they have determined some methods work better than others. One experiment that involved placing shell-filled bags around a cultch ridge mound seemed promising, but with nothing to anchor them, all the shells dispersed. More promising are experiments using circles of cultch, as well as concrete “castle blocks’’ that stack upon each other.
The project this summer is to decide what to do next.
“We’re getting close to proposing the next step,’’ said Prescott. “We need to go big. We’re working with coastal geologists to decide how to proceed.’’
We pause to watch a razor clam partially ooze from its shell and burrow into the sand. Moments later, it jackknifes and disappears beneath the seaweed strewn surface, reminding us that this “laboratory’’ is a living, diverse biosystem.
“The science behind this [reef project] is so interesting,’’ said Celeste Young, a biology teacher in Great Barrington. “I like the statistical analysis and seeing the experiments that failed.’’
Lynn Stelman of San Francisco agrees. “I enjoyed seeing research in action. Seeing the things that work and don’t work. It’s very refreshing.’’
Why should we care so much about restoring the reef? An oyster filters 50 to 60 gallons of water a day, and healthy shellfish populations that are not disturbed act as a filter.
“I believe that shellfish is our salvation to have clean coastal waters,’’ said Prescott. “This is the future.’’
The reef restoration project has been years in the making, and is supported by the shellfish advisory committee and Wellfleet’s Board of Selectmen and its shellfish constable. Prescott is pleased to have brought oyster farmers and scientists together to sit at a table and talk.
“You have to start the dialogue of how to live in this harbor,’’ he said. “Dialogue creates a picture and understanding of how the ecosystem works. It makes for a strong social community. We’ve introduced ‘oyster the natural habitat’ into the conversation, rather than just ‘oyster the product.’ ’’
As we head back across the flats and climb the wood stairs to the van that will ferry us to the Nature Center facility (where there is a wonderful exhibition about the project, with examples of the concrete balls and blocks), the talk turns to eating oysters.
“I don’t know much about oysters and restoration, but now I might have to try and eat one,’’ said Young.
“We’re going to the Beachcomber now for oysters,’’ said Chris Rudomin of Bolton.
I’m ready for a dozen or so myself. This is, after all, the capital city of oysters and it would be a shame not to sample them.
But I pause for a moment at the top of the wood stairs and survey the sandy expanse.
“If this works, in 25 years there will be a whole less sand out here,’’ said Prescott. “You’ll be standing on layers of oysters.’’
Necee Regis can be reached at email@example.com.