Two gray seals swim near the shoreline of Duck Island at the Isle of Shoals on the Maine-New Hampshire border. Credit: Rich Beauchesne | Portsmouth Herald

KITTERY, Maine — At any given time, approximately 600 seals splash, bathe and feed around a modest mass of rocks six miles off the coast of Maine, the northernmost of the Isles of Shoals.

These seals, both gray and harbor species, have made a resurgence in local waters over the last two decades following the imperative enaction of federal protections. Prior to the 1970s, the species had essentially been extirpated in Maine and Massachusetts, after being hunted for their pelts, and killed as competition for fish, said Jennifer Seavey, executive director of Shoals Marine Laboratory on Appledore Island, a joint program between the University of New Hampshire and Cornell University.

Since 2011, Seavey and her staff have been monitoring the seal resurgence at Duck Island, an effort led by Andrea Bogomolni, a researcher from Wood’s Hole Oceanographic Institution. The work is conducted with undergraduate interns, and each summer, two students learn the monitoring methods, which are done by boat and with very specific tracking technology and procedures.

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The monitoring program runs from May to August, Seavey said, and the interns take to the water approximately 30 times, the boat running a specific transect around the island. Photographs are taken on the same transects each time, where the laboratory uses the unique pattern on the seals’ fur to identify them as individuals.

“The metrics they are looking for are survival, entanglement, injuries or health indicators, entire counts of population,” Seavey said. She called Duck Island a “haul-out” site, a surface that has the right circumstances of minimal human impact and the elevation seals desire.

“There’s kind of a nice combination of ideal conditions on Duck Island and it makes it a very important location, well-populated site for the Gulf of Maine,” she said.

The average count of seals in the area is approximately 600, Seavey noted, but that number can reach as high as 900 and as low as nine.

“There’s some variability but it’s pretty consistent,” she said. “The number one thing leading to a very low count is activity in the water by boats and people, especially if they’re closer than 150 feet.”

The seals are protected under the federal Marine Mammal Protection Act, which states the public cannot disturb a marine mammal. Seavey called it “a serious level of protection,” but it wasn’t always in place.

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The protections were enacted in 1972, long after marine mammals had been hunted and killed for years, essentially erased from the New England waters. The act was in response to increasing concerns among scientists and the public that significant declines in some species of marine mammals were caused by human activities, according to the National Marine Fisheries Service.

Now, penalties for violation of the Marine Mammal Protection Act can be up to one year imprisonment, civil penalties up to $11,000, and forfeiture of the vessel involved, including penalties for that vessel up to $25,000, according to NOAA. In 2017, a Maine boat captain was sentenced to three days in jail and ordered to pay a $1,000 fine for shooting and killing a seal off the coast of Acadia National Park, as reported by the Portland Press Herald.

“It’s believed there were no gray seals left at all, and almost no harbor seals,” Seavey said of the New England waters prior to 1972. “This comeback has really been kind of delayed. Gray seals were only breeding in Canada, it took them a while to come back. In the late ’90s through today we have more of a resurgence of them, and that’s why people are really starting to notice them.”

In a survey release in 2017, David W. Johnston, assistant professor of the practice of marine conservation ecology at Duke University’s Nicholas School of the Environment, said 30,000 to 50,000 gray seals were now estimated in the waters off the southeastern Massachusetts coast.

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Harbor seals can live up to 30 years and weigh 285 pounds, while gray seals can live up to 50 and weigh 800 pounds. In tracking entanglements, Seavey said harbor seals are often more entangled than gray seals, and their survey results show it can be as high as 14 percent of the harbor seals, and 11 percent of the gray seals.

Seavey said one of her staff’s remaining questions is where exactly the seals go in the wintertime, when they aren’t hanging around Duck Island. They’re hoping to purchase a high-resolution digital streaming camera and “put one of those on Duck Island itself so we can remotely, without any impact, monitor what they do in the winter.”

The presence of seals at Duck Island is also a good indicator of overall ocean health, she said, as there is clearly enough food in the region to increase their numbers.

The Shoals Marine Laboratory’s work with the seals is “highly regulated.” Its federal permits require it to send annual reports of its work and tag every photograph taken.

Seavey called the return of the seals “a rare celebration,” as the public tends to hear a lot of sad environmental stories.

“Who doesn’t love seals?” she said. “They’re such curious animals and you can just tell that they’re intelligent. They’re just fascinating. And I think this is a rare positive story in the conservation world.”

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