Ten Maine-based aquaculture and fisheries professionals visited Aomori Prefecture at the northern tip of Japan’s main island of Honshu from 1 to 10 October to observe scallop farming techniques. The trip was subsidized by the United States-Japan Foundation.
Hugh Cowperthwaite, fisheries project director at Coastal Enterprises Inc. (CEI), based in Portland, assembled and led the delegation. CEI, an investment company specializing in funding socially responsible business, plans to buy Japanese machinery to expand scallop farming in the state, and observing the machines in action was a part of the itinerary.
Other members were Don Hudson, chair of the Maine Aomori Sister-State Advisory Council; Dana Morse, extension associate, Maine Sea Grant College Program; Sebastian Belle, executive director, Maine Aquaculture Association; Chris Davis, executive director, Maine Aquaculture Innovation Center; Nate Perry, Pine Point Oyster Company LLC; Gordon Connell, F/V Zephyr, commercial fisherman; Marsden Brewer, F/V Lindsay Marie, commercial fisherman and aquaculturist; Robert Brewer, commercial fisherman and aquaculturist; and Matthew Morretti, president of Wild Ocean Aquaculture LLC.
The three machines CEI intends to purchase using a grant from the Maine Technology Institute are all made by Mutsu Kaden Tokki Co., Ltd., based in Mutsu City, Aomori. They are meant to save labor in the “ear-hanging” method of suspended-line scallop aquaculture.
While some scallop aquaculture is carried out in Maine, in the past, aquaculturists in the state have relied on the method of keeping the scallops in cages or trays. The Japanese, on the other hand, drill a small hole through the shell near the hinge. They push a series of plastic pins through a rope and then attach a scallop on each side of the rope by running the pin through the hole in the scallop shell. The rope is then suspended from a float.
Two trials in Maine using the ear-hanging method and have shown good growth: Maine Scallop Company has a crop of scallops on ear-hung lines in Casco Bay, and Maine Sea Grant’s Dana Morse is studying growth rates, biofouling and water temperature and assessing the yield and market value of ear-hung scallops on the Damariscotta River. But drilling and attaching the scallops by hand is too labor-intensive to be economically viable. The machines will be tested to automate the process.
The three machines, funded by a USD 68,500 (EUR 62,160) Maine Technology Institute grant, are a scallop aquaculture cleaning machine for 45,270 (EUR 32,000) to remove biofouling such as seaweed and barnacle growth, a scallop-drilling machine for 11,320 (EUR 10,270), and an automatic age-pin setter for 11,900 (EUR ). The plastic pins have different colors so that the age of the scallops can be easily seen. The total cluster grant to CEI’s Fisheries Project, is USD 134,189 (EUR 121,760). Over a two year period, CEI will work with Portland-based Maine Scallop Company to demonstrate the financial feasibility of growing sea scallops using the Japanese “ear-hanging” technique.
Even if the technique is adopted, there will still be significant differences between the Maine and Aomori businesses. American regulations allow only the adductor muscle to be sold, as it is less affected by red tide toxins than other parts of the animal. Japanese, on the other hand, often eat the whole scallop, apart from the digestive gland, grilled on the half-shell. And Japan produces the sea scallop species Patinopecten yessoensis, while the Atlantic deep sea scallop Placopecten magellanicus is farmed in Maine.