August 1, 2004
Oyster farming thrives on the Damariscotta River
by Muriel L. Hendrix
In the past five years, the number of people raising oysters in Maine has more than doubled, and the industry is still growing. This never could have happened, say several growers who have had oyster farms in the Damariscotta River since the early 1980s, without Dr. Herbert Hidu and the tenacity of the people who worked with him.
"There were a lot of people who beat down the brush," says Sam Chapman; "people who plowed through the woods aimlessly."
Hidu was hired in the early 1970s by the University of Maine to establish a shellfish aquaculture program funded by Maine Sea Grant at the Ira C. Darling Marine Center in Walpole. Hidu's broad experience as a pioneer in shellfish aquaculture included work in several places along the Eastern Seaboard and at the National Marine Fisheries Laboratory in Milford, Connecticut, with Victor Loosanoff, a Russian scientist who has been described as the "guru of shellfish biologists." Hidu's presence at the Darling Center served as a magnet for graduate students interested in hatchery and growout techniques for all types of shellfish aquaculture.
"Hidu was very innovative, always looking for new ideas," says Carter Newell of Pemaquid Oyster Co. "His basic thing was for his students to be independent. He told me what I needed to do and then I did it." Chris Davis, also of Pemaquid Oyster and a teacher at the Darling Center, adds that Hidu was very good at designing scientific experiments. "He had a good sense of what was worthwhile and what would be a waste of time," he says. Everyone remembers Hidu's energy and enthusiasm. Chapman, who was hired by Hidu in 1972 to manage the new aquaculture center, describes him as "an adult teenager all his life. Anything you did, he made a competition out of it," he says. "He really kept people hustling."
"The oyster work Herb founded really got the oyster industry started in the state of Maine," Chapman adds. From the beginning, he says, Hidu wanted to develop oyster and other shellfish aquaculture opportunities for fishermen as an additional way for them to make money working on the water. However, says Chapman, "At first, only retired people had the time and money to make oyster aquaculture work. But now, because of the availability of seed oysters and the way the technology has evolved, anybody with a boat and motor and access to a clean area can grow oysters."
The industry had to go through years of experimentation with techniques for hatchery culture and nursery and growout methods before this became possible. Early researchers and farmers tried out oddly shaped floating nurseries made of wood, plastic and various types of screening; stacked growout trays, trays planted on the bottom and oysters planted loose on the bottom. Finally, most settled (for awhile, at least, and with several variations) on a combination of surface and bottom culture. They use floating bags in the early stages and plant oysters directly on the bottom for final growout. "We always joke about the technology graveyard - all the stuff we've gone through," says Newell. "We've struggled for so long."
The earliest wave of growers focused on the European or Belon oyster, Ostrea edulis, which in those days sold for around 50 cents apiece, whereas the American or Eastern oyster, Crassostrea virginica, brought only 15 or 20 cents apiece. In the late 1970s, when a winter die-off decimated 90 percent of the European oyster crop, almost all of the early growers decided to move on to other ventures, and a new wave of oyster farmers came on the scene: people who had done graduate work with Hidu.
On the Damariscotta River, they include Dick Clime of Dodge Cove Sea Farm, who started in 1976 with European oysters and made the transition to American; Newell and Davis, two of originally six and now four partners at Pemaquid Oyster Co., who began raising American oysters in 1985 and opened their own hatchery in 1996; and Bill Mook of Mook Sea Farms, who in 1982 worked in and then ran a hatchery in Bristol, opened his own hatchery in 1985 and later began raising oysters to maturity.
In the early days of oyster aquaculture, growers built much of their equipment out of materials they scrounged or bought at hardware and department stores. Many still do this, although commercial equipment is now available. Davis says for about 15 years Pemaquid used homemade wooden nursery trays built of hackmatack with window screening held on by oak laths. "They weighed 15 pounds dry and about 60 pounds when they were waterlogged, fouled with marine animals and plants, and full of oysters," he says. Pulling them for cleaning (fouling clogged the mesh and prevented water from circulating freely through the trays to bring phytoplankton to the oysters) was backbreaking work.
On a trip to New Brunswick in the late 1990s, Newell and Davis discovered commercially produced plastic mesh ("ADPI") bags that could replace the wooden trays. These weigh two pounds when they're put in, and two pounds plus the weight of the oysters when they come out. They are easy to maintain, requiring a simple flip once a week so marine organisms that latch onto them will dry out and fall off. (The wooden trays sank too low in the water to allow organisms to dry.)
In the early 90s, American oyster farms were seriously threatened by a die-off caused by juvenile oyster disease (JOD). "We lost more than 90 percent of our crop," says Davis. "Everyone suffered from it." Fortunately, there hasn't been a similar die-off since. Davis attributes that to more careful management techniques such as ensuring that oysters, which, if possible, are put into ADPI bags in May, have grown large enough to withstand disease by the end of July and early August, when JOD is most prevalent. Pemaquid also has experimented with putting out seed oysters in August, after the greatest risk of JOD has passed, and with using alternative remote sites for nursery oysters, places where JOD has not been detected.
Mook says he believes surviving oysters, having grown in waters containing JOD, have gained some immunity and genetic resistance to the disease. Researchers continue to work on developing strains of oysters resistant to JOD.
Clime of Dodge Cove Marine Farms, who was issued one of Maine's early aquaculture leases, says he and a partner started out raising the European oysters on lantern-shaped nets, which were at that time used by the Japanese for scallop aquaculture. Keeping these nets clean was a major challenge. They used a power spray to wash off the organisms, working their way down the line of 1,500 lanterns. "It was like painting the Golden Gate Bridge," Clime says. "You'd start at one end and by the time you reached the other, you had to start again." Also, they found the European oysters were more time-consuming, and less economical to raise than American oysters because they could not survive winter water temperatures in the upper Damariscotta where the Dodge Cove lease was located. The lanterns had to be moved each winter to deeper waters, then brought back up the following summer.
Newell of Pemaquid Oyster says a paper by Hidu led him to a site Pemaquid still uses for growout. "I dug out this old paper Hidu had written where he assessed the best places to grow the different types of oysters up and down the Damariscotta River," he says. "It turned out the best spot for American oysters was in front of Mary Parmley's house." Parmley, now 80, has had a lease on that spot since the early 1980s; one of Pemaquid Oyster's leases is nearby.
Newell says Pemaquid had the first upweller on the river because he attended a formal dinner given for the Shellfish Growers Association in Britain at the Tower of London. (Because upwellers, often used for the first stages of nursery growth, pump more water past small seed than the tide can carry, they deliver more nutrients and speed up growth.) "I was sitting next to John Bayes, who invented the upweller," Newell explains. "Bayes drew the design for an upweller on a napkin, and I brought it home."
Recently, as part of the Fishermen's Retraining Project, fishermen have had the opportunity to learn techniques of oyster (and other shellfish) aquaculture. In 1998, Maine Aquaculture Training Institute (MATI), started by the owners of Pemaquid Oyster, established a 10-week training course. It offers classroom instruction by industry experts and takes prospective shellfish farmers on field trips along the East Coast to observe shellfish aquaculture operations. Jesse Leach of Penobscot completed the first MATI course and has been a leader among traditional fishermen in transferring a lifetime of fishing skills to this new venture. About 50 people have completed the course; close to one-half are growing shellfish.
Davis, who teaches many of the classes for MATI, is also working with Maine Sea Grant on an Oyster Gardening Project for citizens of Damariscotta and Blue Hill. (WWF, June 2004)
Despite setbacks, oyster aquaculture has come a long way from its beginnings under Hidu's tutelage. Approximately 30 growers and seven hatcheries were listed in 2003, up from 10 growers and a couple of hatcheries in 1993. The Damariscotta River oysters, which are sold either directly or through distributors to restaurants and seafood markets from Toronto to Atlanta, currently retail for about $1.00 apiece locally. "We can't grow enough to meet the demand," Davis says.
Hidu, who retired in 1992, has moved on to new challenges. "A lot of people linger with their old careers when they retire," he says. "I couldn't do it halfway." He has turned to a new sort of farming, raising hostas, a hobby he says "is getting out of hand." He also spends a good bit of time painting, hiking and says he considers himself "a professional golfer."
First of two articles. Next month: challenges and opportunities facing the oyster aquaculture industry and profiles of several growers.
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