Shellfish expert delivers online talk

TOMS RIVER — Dr. Lisa Calvo, a marine scientist and the aquaculture Extension program coordinator for Rutgers University Cooperative Extension Service, detailed New Jersey’s shellfish aquaculture industry during a virtual workshop held in October.
Calvo directs Extension and research efforts at Rutgers’ Haskin Shellfish Lab in Port Norris on the Delaware Bay, where there are a growing number of oyster farmers.
New Jersey has 21 clam farms and 18 oyster farms with a combined worth of nearly $7 million.
New Jersey’s clam farms are worth $2.2 million while its 18 oyster farms are worth $4.4 million.
“When we’re talking about aquaculture, the definition I like to use is from the Food and Agriculture Organization of the United Nations: they define aquaculture as farming of aquatic organisms, including fish, mollusks, crustaceans and aquatic plants,” Calvo said.
“The farming implies some sort of intervention in the rearing process that enhances production, such as regular stocking, feeding and protection from predators,” Calvo added.
In looking at global statistics, Calvo said fishery harvests have remained static through the last several decades while aquaculture efforts are increasing.
“With global population increasing, we’re really going to see the need for additional aquaculture to support food production and all the population growth,” Calvo said. “In the U.S., five species farmed right now are oysters, clams, salmon, mussels and shrimp, but oysters are the top species by value.”
A national strategy set forth by the Obama Administration in 2016 recognized that “aquaculture enhances coastal resiliency, creates jobs and improves food security and human nutrition and can be used as a valuable tool to rebuild some protected species and their habitats.”
Calvo said shellfish farms are located both in the Delaware Bay and on the state’s Atlantic Ocean coast and there are four species currently being cultivated by shellfish farm operators.
“Hard clams are primarily being cultivated in the Atlantic coastal areas and they are primarily grown under nets which protect them from predators,” she said. In 2019, the DEP estimated there are about 6 million clams harvested annually here in the Garden State.
“A new species being evaluated is the bay scallop. Bay Scallops in the wild are found in back bay areas and on the bottom with sea grasses. Rutgers has done some research along these lines and currently there are about 12 different farms growing bay scallops as a trial species,” she said, “so we’re currently looking forward to commercial production in the next year or so.”
While there are wild harvest fisheries for surf clams, they’re also being looked at as an aquaculture species to raise on farms, she said, “and in that capacity, these clams would be sold at a much smaller size; in other states they’re called butter clams because of their very tender meats and delicious flavor.”
Calvo said she and others on the team at Haskin Shellfish Lab are looking forward to having surf clams again and they’re being grown and evaluated on about a dozen working farms.
“Hard clam aquaculture dates back to the 1970’s in New Jersey but the eastern oyster is relatively new, starting in the late 1990’s,” Calvo said.
Calvo organized the bulk of her talk to focus on oyster farming in the Garden State, which has grown rapidly.
“As of 2016, there were 19 farms that reported production of 2.03 million oysters that was valued at $1.37 million dollars at the farm gate. Since that time between 2013 and 2016 we’ve seen about 12 percent growth in production per year.”
In 2019, she said, Garden State oyster aficionados reaped the benefits of this scaling up in oyster farms and new farmers getting their feet with operations in the Delaware Bay.
Oyster farmers carefully monitor three phases of production: a hatchery phase, a nursery phase, and a farm phase. In the farm phase, the farmers transfer their growing oysters to different sized netted bags, working between the tides.
“Once on the farm, young oyster seed will be placed in some type of container, often a plastic mesh bag, and you might start with 10,000 seed in a bag,” she said, noting there are a variety of grow out methods “depending on location and the area you’re farming in.”
Many Delaware Bay oyster farmers use the rack and bag method favored in many parts of Europe. Farmers access the farm by walking onto the beach at low tide, and get their work done before the tide comes back in, usually developing big biceps and forearm muscles over time.
“As oysters grow in size, the farmers can increase the mesh size of the bag and transfer oysters to other bags,” she noted, while deeper waters in the Upper Delaware Bay require a more rigorous gear setup. Calvo showed images of a large cage being pulled up to a hoist on a small ship, filled with fresh oysters.
“Regardless of the method used,” she stressed, “oyster and hard clam farming is a very labor intensive business. It’s very intensive work and typically season is all year long, but the most activity is between April and November.”
Fortunately, there’s been quite a renaissance and accompanying high demand for eastern oysters around the Mid-Atlantic States and elsewhere around the United States.
“The farm-raised shellfish here are of very high quality, consistent and uniform, so our farmers are selling in New Jersey and across the nation,” she said.
In closing, she pointed out the environmental impact oyster farms are having on the Delaware Bay and how oyster farmers are working to market their batches of farm-raised oysters based on their taste, which can vary a great deal.
“Oyster seedlings are filtered by surrounding waters and the flavors of the oysters can be salty, earthy, sweet tasting, that flavor will reflect the unique conditions of the waters and this can change seasonally, so from a dining perspective, oyster eating can become an experience,” she said.
Calvo added they’re a low-fat seafood, high in protein, high in omega-3 fatty acids, rich in minerals like potassium, zinc, iron and magnesium and high in vitamins like B-12 and C.
“They’re not only delicious, they’re also good for you,” she said, offering a quote from Washington, D.C. area restauranteur and author Barton Seaver:
“Eating farm oysters is your patriotic duty: they are not just sustainable, they actually help restore depleted ecosystems. So I tell you, save the world and eat an oyster; redemption on the half shell with lemon and Tabasco!”