March 25, 2019
Down East Latest News | Russia Investigation | Bangor Metro | Maine Bicentennial | Today's Paper

More man-made contaminants discovered in Maine’s harbor seals

Sharon Kiley Mack | BDN
Sharon Kiley Mack | BDN
Seals bask on small rock islands in the sun in the Bay of Fundy between Eastport and Campobello Island in August. Heavy fog this summer off the coast of Maine hampered University of Maine researchers from tracking seals that were equipped with radios earlier this year.

LUBEC, Maine — Some of the most endearing and popular sights off Maine’s coast are the harbor seals. These curious but cautious mammals will silently give a boat the eye, and if it veers too close, will slip off tiny rock outcroppings — where they are bulky and clumsy — to reveal their grace and finesse in the water.

Seals may now be tourist attractions and are federally protected, but they were once considered fisherman’s foes. A 300-pound adult female harbor seal will eat 6 percent of her weight each day — that’s 18 pounds of herring, scallops, urchins and nearly all other fish. Up until 1905 in Maine and 1962 in Massachusetts, bounty hunters were paid $1 for every seal nose they turned in.

But, in a major new study, Maine seal researchers have discovered that the seals’ hearty appetite for fish portends a potentially dangerous bite.

Landmark studies at the Blue Hill-based Marine Environmental Research Institute are proving that Maine harbor seals’ bodies are full of man-made toxic compounds — compounds found in cars, homes and schools.

“It is very scary,” MERI’s Director, Dr. Susan Shaw, said this week. “When we start seeing these chemicals in our oceans, we are really in trouble.”

Shaw has been a worldwide leader in this research. In 2000, MERI launched a long-term research project, Seals As Sentinels: Assessing the Impacts of Toxic Contaminants in Northwest Atlantic Seals, which is an ongoing series of studies examining toxic environmental contaminants in pinnipeds — primarily harbor seals — and their prey fish.

Shaw said that research continued this summer and even more chemicals — newly manufactured fire retardants — were found in the seals.

MERI’s research found that levels of toxic chemicals in Maine’s harbor seals are among the highest in the world. Their bodies contain persistent organic pollutants and toxic metals such as mercury, polychlorinated biphenyls , dioxins, DDTs and other pesticides.

Shaw said that many of these toxic compounds are so persistent that once they enter the ocean environment, they can recycle in the food web for decades. “These seals are eating the same fish we eat — herring, hake, flounder, mackerel.”

MERI’s finding of brominated flame retardants, including the widely used flame retardant Deca-BDE, in seal tissues influenced the Maine Legislature’s decision to ban that chemical compound as of 2010.

However, the companies that manufacture such compounds since have switched to elements other than Deca — chemical cousins, Shaw calls them. “These compounds are nearly identical to the banned Deca. They just have new names, such as Firemaster 550. We are now picking up those novel, toxic compounds in the seals and they are building up in the tissues of the seals,” Shaw said.

Shaw said such fire-retardants are found in many items including furniture, sneakers, lumber, bed padding, automobile headliners, carpeting and baby strollers. As the products break down, she added, the chemicals are released as contaminated dust in the air.

“Without such studies,” Shaw said, “we would never know which chemicals are increasing in tissues and which pose the greatest health threat to marine animals and people. Information gained from MERI’s novel compounds study is cutting-edge and will inform and guide future public policies to protect our oceans and human health.”

Shaw said that the toxic soup that is being created in the world’s oceans indicates that these chemicals are not only rising to the top of the ocean’s food chain — seals — but are present in fish meant for human consumption as well.

The presence of flame retardants in seals “points to the weaknesses of our country’s regulation of toxic chemicals,” she said.

In August, Shaw was a speaker at the Brussels Flame Retardant Science and Policy Meeting, which was intended as an exchange of information between academic and government scientists and nongovernmental organizations. “There is a big debate between the scientific and flame retardant industry as to the safety of these chemicals,” she acknowledged.

Chemical companies that opposed the Deca ban in Maine maintained that the chemical is safe, well-researched and extremely effective at stopping or slowing the spread of deadly fires.

Chemtura of Middlebury, Conn., one of the country’s largest manufacturers of fire retardant chemicals, states on its website: “Chemtura is committed to the concept of Sustainable Development, which is to minimize the imprint that our operations and businesses leave on our collective health and safety and that of the environment, both for ourselves and for future generations.” A spokesman for the company refused to comment Thursday.

In a statement on its website, the European Flame Retardant Association states: “Many studies have been carried out and show that modern flame retardants, when appropriately applied, can be used in consumer products without significant risk to human health or the environment.”

The results of this summer’s research by MERI scientists is still being compiled, Shaw said, but once the data is processed, MERI will be asking the Legislature to ban all flame retardants in the state of Maine.

“Maine is an environmental leader and once they are banned here, other states will follow,” Shaw said. “The hope is that will drive the federal government to ban them, as it did with Deca.”

Throughout Down East, other researchers are also looking closely at harbor seals.

Earlier this year, University of Maine scientists attached tiny radio transmitters — each about the size of a roll of pennies — to 24 harbor seals in Rockland and in Chatham, Mass., with a plan to survey the adult population along the coast.

Mother Nature, however, had other ideas. Heavy fog hampered the research and ruined an entire season of work.

Dr. James Gilbert at the University of Maine in Orono said this week that the last seal population survey was conducted in 2001 and this year’s plan was to conduct aerial surveys in May and June, using the radio signals to find the seals, photograph them and count the population. Those counts would then be used to estimate the overall population.

“But we got fogged out,” Gilbert said this week. “We only got one and a half days in the air and we were unable to track any seals at all.” The researchers tried into August to conduct the surveys with no success. Gilbert said it is particularly disappointing since the seals are now shedding their fur during the seasonal molt and they will also shed the radio transmitters.

A survey taken in 2001 indicated there were at least 100,000 harbor seals in North Atlantic waters ranging from Canada to New Jersey, Gilbert said. The greatest numbers are off the coast of Maine, where they can easily be spotted lazing on ledges and small rocky islands. In 1972, a count on Sable Island, Nova Scotia — an important birthing area — showed that 120 pups were born that year. Now, scientists estimate 70,000 pups are born on that protected island every spring, he said.

Gilbert said seals are federally protected by the U.S. Marine Mammal Protection Act of 1972 which makes it illegal to chase, shoot, kill or harass seals. The act also mandates a population survey every three to five years. Maine, however, has been unable to complete another since 2001.

Gilbert said it is important to keep track of the seal population because it has a unique life history — seal mothers only nurse their pups for 24 days and then cease all parental support. There is also the interaction between people and seals which needs to be taken into consideration, he said. Gilbert said that the population count could also be important information when considered alongside MERI’s research. The seals’ migration patterns — harbor seals that summer in Maine have been found as far south as South Carolina — are also a topic of study.

Have feedback? Want to know more? Send us ideas for follow-up stories.

You may also like