Course cultivates shellfish lovers who want to grow their own
Amber Tonry has never eaten an oyster,
raw or otherwise, but she will get her chance later this year when the
oysters that she and her husband Rick are raising in the Damariscotta
River get big enough. The Tonrys are taking a new University of Maine
course that is teaching people how to grow the prized shellfish for
their own use, just as they would raise tomatoes or lettuce in their
University of Maine Cooperative
Extension Associate Dana Morse, who is affiliated with the Maine Sea
Grant College Program, and Chris Davis, an oyster grower and director of
the Maine Aquaculture Innovation Center (MAIC), are the instructors for
the oyster garden course held in Damariscotta and Blue Hill. Starting in
March 2004, they focused on oyster biology, water quality and
aquaculture regulations. When the 18-month course ends this fall,
students will have a broad view of how humans affect coastal ecosystems,
and the practical skills to grow a valuable shellfish.
To help defray the cost to students, Maine Sea Grant, the Maine State
Planning Office and MAIC provided financial support, working in
partnership with the Damariscotta River Association, Pemaquid Oyster
Co., and Bagaduce River Oyster Co. The course is designed for
noncommercial oyster growers; Davis teaches a separate course for people
starting an oyster business.
Last summer in the
Damariscotta River near Dodge Point, the novice oyster farmers
aboard the Seaducktress deployed their spat
in plastic floating trays.
The tiny oysters, each
less than a quarter-inch long, were held in the black trays by
orange bags like the one being emptied by Lincoln Brown.
By the end of the first
summer, many of the oysters were nearly 2 inches long. They wintered
in a wet lab at the Darling Marine Center before returning to the
river this summer.
Retired professor Donald
Huffmire and Savick Harvey check on the floating nursery.
Photos by Dana Morse
and Linda Healy
The oyster gardening students bring a
variety of experiences to the task. They include a commercial fisherman,
a high school biology teacher, a retired university music professor, and
a grandmother and her grandson. Morse remembers the excitement of the
first class gatherings. "They wanted to get their babies in the water
and watch them grow," he says.
In mid-summer, the students got their chance. They received about 1,000
spat, baby oysters less than a quarter-inch long that were produced at
UMaine's Darling Marine Center in Walpole, Maine. Students placed their
spat in containers, also called "bags," made out of sturdy, fine-mesh
plastic. Attached to plastic floats, the bags are designed to stay on
the surface of the water and provide oysters with constant exposure to
their primary food source, the microscopic plankton that flow back and
forth with every passing tide. Students were responsible for mooring
their bags in an estuary or bay at a location specified in their
short-term state permits.
For the next five months, students tended the bags weekly, keeping them
free of fouling by algae and occasionally dividing their growing crop
into new bags to avoid overcrowding. By late fall, the oysters had grown
to nearly 2 inches long.
Morse traces the first oyster garden program to the Chesapeake Bay,
where, in the 1980s, the goal was to restore overharvested reefs.
Subsequently, the idea spread to North Carolina, New Jersey and New
York's Long Island Sound. Some programs aimed at oyster reef
restoration, while others served people who simply wanted to eat their
own homegrown shellfish.
"One of the main things they (instructors) found was that it was really
engaging to people," says Morse.
"They were getting an education in biology and ecology." Among the
topics covered in the UMaine course is phytoplankton. Sarah Gladu,
coordinator of Cooperative Extension's volunteer phytoplankton
monitoring program, taught students how to collect phytoplankton with a
net and identify them with a handheld microscope.
For Amber Tonry, participating in the UMaine course seemed a natural
extension of living by the shore. The Tonrys are lobstermen and operate
their boat, the Sea-ducktress, from their dock near Dodge Point on the
Since the Tonrys were on the water on a daily basis, they were able to
check on their bags regularly. During the 2004 Oyster Festival in
Damariscotta, they also took people out to get a firsthand look at their
crop. "It's amazing to see how easy it is. You have to tend them once a
week, but they pretty much take care of themselves," says Amber.
Mark DesMeules, executive director of the nonprofit Damariscotta River
Association (DRA), is also taking the class. DesMeules says his whole
family, including his children, love to eat raw oysters.
The oyster garden course dovetails nicely with the DRA's mission to
educate people about the health of the river and estuary, DesMeules
says. "(The course) helps people become more knowledgeable about the
river as an ecosystem and about the importance of clean water. We've had
discussions about how land use affects water quality and about invasive
species. With this project, we're using a native oyster (the American or
Eastern oyster, Crassostrea virginica). European oysters have been put
into the river, and we don't really know if that could be a problem or
While raising oysters gives people a new understanding of the coastal
environment, the course also has led participants to consider competing
uses of the river. Among lobstermen, kayakers, shoreland owners,
aquaculturists and others, the potential exists for conflicts. Coastal
waters are a public resource, and students got a taste of how public
policies address one aspect of this issue — oyster aquaculture — through
the state permit application process.
"How many oyster leases can you have? You also have fishermen who need
access to their docks. Shoreland owners like the views from their homes.
Kayakers really don't want to be paddling through lots of oyster bags,"
Oysters go into a period of hibernation during the winter, and growers
typically remove them from the water or anchor them to the bottom where
they are safe from ice and the occasional Arctic chill. Before ice began
to accumulate on their bags last winter, most class participants stored
their oysters in tanks at the Darling Center. Others put them in
refrigerators or down on the sea floor.
By this past May, the young oysters were back in the sunlight at their
lease sites, where they continued feeding and growing. Students were
learning about oyster predators such as birds and the diseases that can
threaten their crops before they mature.
This fall, the oysters should reach about 3 inches in size — and be
ready to eat. While they could continue to grow (American oysters can
reach up to 8 inches long), Morse and Davis plan to host an oyster feed
to celebrate the students' success.
by Nick Houtman
for more stories from this issue of UMaine Today Magazine.