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Originally published in the Historic Nantucket Vol. 43, Number 3. (Fall 1994) p. 77

What It May Become : Aquaculture: Tomorrow's Fishery
by Douglas K. Burch

There's a farm out in Polpis that may very well be the harbinger of the fisheries of tomorrow.

Ten acres of the shallows at the northeastern quarter of the entrance to Polpis Harbor have been home to Martin Ceely's oyster farm since 1980. He states: "We chose this particular location because in order to get a grant to begin with you have to go into an unproductive area where there are not a lot of shellfish for commercial or domestic taking. This whole area had to be surveyed by the state-—a random survey to find out what was here. I knew this place was unproductive and I knew this would be a good place to grow oysters because you've got fresh water coming out of the estuary over to the east and the Polpis Harbor on the south. You get a lot of food early in the spring and a lot of food late in the fall and it sweeps right across here, so it's a very good area to grow oysters. It always was.

"Years ago there was a large natural bed of oysters over in what's known as the meadows at the entrance to Polpis Harbor till they got wiped out. That's the reason I took this area-—knowing that it wasn't productive."

Today, long rack systems of rebar frames supporting plastic bags holding millions of oysters in various stages of development stretch hundreds of feet across the flats. In the early days of the farm large seed was merely placed on the bottom and allowed to grow. Severe wind storms blew most of the seed up on the beach, and more than 80 percent of the potential crop was lost.

Following that disastrous experience, floating racks fastened together with chains served as pens to contain the growing oysters, but once again severe storms broke up the gear and another crop was lost. Today's racks, firmly secured to the bottom, hold together well, can withstand the pressures of all but hurricane-force storms, and have successfully produced an initial crop of mature, market-sized oysters.

There's a lot more to oyster farming than merely planting seed and waiting for it to grow. It takes three to five years to grow an oyster to market size. They don't all grow at the same rate. Ceely explains, "If you start out with a million oysters, and they all live, in three years you'd probably have about two to three hundred thousand ready for market; the fourth year, six hundred thousand; and it would take that fifth year to get the final two hundred thousand to market. The rate of growth depends upon the quality of the water, the food in the water; but what determines one oyster to grow faster than another we don't really know."

Adult oysters are taken from the farm to the town's marine laboratory on Brant Point, where they spawn. The hatchery has been developed at the lab to assure that only disease-free seed is planted in the farm. The larval oysters in the hatchery attach themselves to tiny individual pieces of ground-up oyster shells rather than growing together in a clump, as is often the case in nature. When the larvae have started to develop their shells, the seed is returned to the farm where the growing process takes place.

The farm produces these "single set" oysters exclusively. Single-set oysters are the top of the line, served at raw bars, for Oysters Rockefeller, and for other treats requiring single shellfish as opposed to bulk oysters as in stews and chowders.

Oyster farming is a labor-intensive business. The oysters have to be handled at least five times before they have grown to market size and are ready to be shipped off. The tiny seed oysters, about the size of the nail on your little finger, are put into plastic bags with an eighth-inch mesh. Each eighth-inch bag contains 5,000 oysters. As they grow, they are moved to larger bags, or pens. There are 1,600 oysters in each of the quarter-inch pens, 600 in each of the half-inch pens, and 200 in the final, three-quarter-inch pens, which are removed from the racks and laid on the bottom for the last few weeks of growth.

If the crop holds up well, the return on the yield is sufficiently high so that the whole enterprise is economically feasible. Once the sequence is established and new seed is set as the mature oysters are harvested, the whole three-to-five-year cycle is self perpetuating. If natural perils don't cause too many casualties along the way, the oyster farm becomes a productive and profitable business.

Ceely expects to harvest his first profitable crop of marketable oysters in the summer of 1995, provided that winter storms and temperatures are not too extreme. "Whatever else," he says, "we have to remember that we're dealing with Mother Nature here. We can do everything possible to assure a safe and healthy set of oysters, to protect them from predators, keep them clean and uncrowded; but a bad storm or a long deep freeze can cancel out an awful lot of hard work, just as in any other kind of farming."