Seaweed—The Other Fishery

by Brenda Tredwell

The golden-brown kelp grows in pristine, secluded bays in downeast Maine, and is harvested during the spring and early summer.Photo: Maine Coast Sea Vegetables

Cruising northbound from Belle Isle Strait aboard USCG Nanok, Thaddeus Novak wrote that after his finger was smashed by an anchor, a red line ran up his arm. When the medic wanted to amputate, Nanok’s Norwegian Capt. intervened, applying his “home made cure-all medicine made from sea weed” to the wound. The infection cleared, rescuing Novak from further medical consequence.

The seaweed processed in Rockland is used to make carrageen, a nutrient added to animal and plant foods. This is a high volume low retail value business. In Canada, some seaweed is harvested from boats rigged with cutting machines. The Rockland plant buys seaweed from many places and has been buying more Maine harvested seaweed in recent years.

Seaweed harvested for human consumption is a low volume, high retail value business. It requires a lot of hand work. Of the four most common varieties for human consumption harvested in Maine, kelp, dulse, laver and alaria, kelp and dulse are the most common. Kelp has a long broad leaf and is seen on the beach at low tide. It is harvested in 2-3 feet of water at low tide. Dulse has a smaller leaf and clings to rocks.

The Maine department of Marine Resources (DMR) statistics report 3.54 million lbs. of seaweed was landed in Maine in 2004, a harvest valued at $202,482. The DMR collects mandatory catch information for the licensed fishery. In the Gulf of Maine and Bay of Fundy, over 250 seaweed species grow in intertidal and subtidal zones. Currently, 11 species are harvested in Maine. Harvesters in Taunton Bay plan to work with the Maine Seaweed Council to do a rockweed and kelp assessment, and support sustainable commercial and recreational harvests. “For every two hours of cutting, it takes a crew of four to five of us maybe five hours to flake and cull,” said one harvester, adding, “It’s a pretty niche market.”

At Maine Sea Coast Vegetables in Franklin, Shep and Linette Erhart work with University of Maine’s Department of Food Science and Human Nutrition promoting sea vegetables. In 1971, the Erhardts started wild-crafted seaweed, harvesting 200 Ibs. They currently land 50,000 lbs., gathering from April to October, and employ 40 people. In 1992, their company became the first organically certified seaweed processors in the world. In Asia seaweed is a major component of the typical diet. Lower cancer rates there have been attributed to their consumption of seaweed. It is used in soups, salads, stir fry and as a salt.

The Erharts noticed after the nuclear accident at Chemobyl, Russia, overseas demand rose for kelp. At Vladivlostok, Russia researchers isolated the polysaccharide “U-Fucoidan”(contained in kelp) as a radio active antidote. Studies conducted at Canada’s McGill University supported those findings. Researchers discovered alginic acid (contained in kelp and alaria) “appears to absorb radioactive elements and heavy metals from the human digestive system.” Toxins built up in the body from repeated exposure are absorbed by seaweed and carried out of the system.

Fishermen and boatbuilders exposed to diesel fumes, fiberglass traces, copper bottom paint, and styrene resin might benefit from adding seaweed to their diet. While researchers continue to study seaweed, Erhart cautions, “There is no magic bullet.” Studies are inconclusive, but nutrient rich seaweed is an important source of iodine. In 2000, “A National Health and Nutritional Survey found that over the past 30 years, iodine intake has decreased 50%,” says Erhart. “Iodine, found in every cell in the body, is necessary for all metabolic function. Healthy levels of this element produce thyroid hormones, contribute to healthy fetal development, maintain the prostate and discourage fibroid growth.” Unlike relatively strong table salt, seaweed has several mineral salts that are easier on the body.

The kelp will be dry and ready for storage in 8 to 12 hours. Kelp is 80 to 90 percent water. Photo: Maine Coast Sea Vegetables

Maine Sea Coast Vegetables’ lab tests its harvests for traces of pesticides, herbicides, diesel, range and organic oils, lead, mercury, arsenic, cadmium, yeast ecoli and microbiological contamination. Their monitoring system allows them to mark each package with the date harvested, species, location and harvester.

Larch Hanson of Maine Seaweed Company in Steuben works in flat bottom garveys, a hull design developed in the Chesapeake Bay Oyster fishery with a centrally placed inboard engine that maintains stability while landing in surf. Their hulls are preserved with vegetable oil rather than copper paint and great care is taken while harvesting to keep engine pollutants far from the plants. He takes along a tow boat powered with a four-cycle engine, separate container boats and an eight foot rowboat. Hanson and the other harvesters use the lowest tides occurring on full and new moons to maximize yield during short harvesting windows.

Long broadleaf kelp is cut in April and May. Seaweed must be processed immediately after cutting, and dried within 48 hours in temperatures below 100 degrees F. Small plants are flaked on nets and long ones hung from a line in the sun and wind, then further processed in a solar/fanned drying room with backup wood heat. “Two thousand wet pounds equals two hundred pounds after drying,” Hansen estimates.

Alaria, known as “wakame” in Japan, grows “about a foot a week,” says Hanson. Alaria is challenging to harvest as it grows in rushing surf. There are about 12 days from mid-May to the end of June in Maine, that produce the best product.

The dulse harvest comes during July and August, and is done on offshore islands. Although Hansen said he has harvested out of a canoe in February to supplement a short supply. Less plentiful in the U.S. than on Canada’s Grand Manan, where 95% the world’s dulse supply is harvested, Hanson distributes dulse gleaned from Maine’s coast. Kelp and alaria are more plentiful here.

Alaria is the most difficult to harvest. The footing is treacherous, and one eye is always kept on the incoming wave. Photo: Maine Coast Sea Vegetables

A Texas Researcher studying iodine contacted Maine Seaweed while trying to develop an iodine supplement in order to address perchlorate contamination originating in Nevada—where 250 million gallons of the chemical are leaching into the Colorado River that irrigates crops grown in the Southwest and Mexico. Thirty percent of U.S. produce is affected by contaminants from this water system. Perchlorate blocks iodine from the thyroid, creating metabolic disorders. Hanson also works with cancer researcher Jane Teas, affiliated with the Harvard School of Public Health. Teas uses alaria supplied by Hanson in her studies. The cancer resistant diet link in Japan has been partly attributed to a high consumption of seaweed. Japanese men, 50% more likely to smoke cigarettes than Americans, have a significantly lower incidence of lung cancer than Americans. Additionally, older Japanese women have lower incidence of breast cancer in his 1985 research.

Dr. Yamamoto of Japan administered traditional medicine—a mixture of powdered kelp and hot water—to rats, which inhibited cancer cell growth by 95%. Just as plants and herbs—such as digitalis, opium, and valerian root—provide the base for pharmaceutical grade medicines, underwater resources are being researched. Canada’s National Research Council is studying the applications of natural compounds and their use in disease prevention, while Texas and Virginia Techs have licensed their patent for a seaweed based fertilizer designed to prevent cattle and livestock disease to Acadian Sea Plants of Canada.

University of Maine research scientist Susan Brawley is studying Maine’s potential for seaweed culture. Funded by the Sea Grant Program, Brawley and graduate assistant Nicolas Blouin, work with China’s Academy of Sciences and Cooke Aquaculture, studying the symbiotic effects of cultured seaweed and mussels grown near salmon farming pens. Seaweed reduces nitrogen and phosphorus in the water, acting as a bio-remediator, clearing water of fish waste and excess nutrients. Hypothetically, fish farming excesses will enrich the plants. Similar polyculture experiments continue at St. Andrews, N.B.

Seaweed processing for human consumption has potential for growth depending on changes in domestic eating habits. Americans ordering a seaweed sandwich at the drive-up any time soon is hard to imagine. But as the Asian economy grows, so may demand for a high quality version of one of their favorite foods.