Copper, a young harbor seal rescued in Southport in March 2016 after becoming entangled in fishing line and then treated at Marine Mammals of Maine in Harpswell, was released from Narragansett, Rhode Island, after four months of rehabilitation at the Mystic Aquarium in Connecticut. Credit: Courtesy of Marine Mammals of Maine

PORTLAND, Maine — During all of 2017, Harpswell-based nonprofit Marine Mammals of Maine responded to 40 calls about seals in distress along the Maine coast.

Already this year, the organization has been called about nearly 250 seal pups, either dead or in distress, between Portland and Kittery.

On Tuesday morning, executive director Lynda Doughty sent a staff member out to collect another one. In the past three days alone, the organization has taken reports of more than 30 dead seals, mostly harbor seals, on the beaches between Portland and Kittery, Doughty said.

“It’s been pretty steady most of the summer, and then picked up around the beginning of July, and the last few weeks were a little busier, but the last few days have been even crazier,” Doughty said.

Eleven dead seals were found on Saco beaches Monday morning, the Journal Tribune reported.

In addition to the dead seals, about 10 live seals in distress have been reported, including one on Long Sands Beach in York, which was battling a respiratory infection, ​NECN reported last week.

“This is out of the norm for what we normally see,” Doughty said Tuesday.

Doughty said that mid-August is past the time of year that harbor seal pups usually die in large numbers because they’re unable to thrive after weaning.

The seals have been found in varying stages of decomposition, Doughty said, so her organization’s staff is performing necropsies on the fresher carcasses, hoping to discover a cause.

In June, the Newport Daily News in Rhode Island reported that six seals washed up dead on Sachuest Beach, the first time a dead seal had been found there in three years.

A significant seal die-off in New England was previously seen in the fall of 2011, when 162 seals — about three to four times the normal number — washed up dead between Massachusetts and Maine, according to the Associated Press. Those deaths were attributed to an outbreak of an avian flu, H3N8, that made the jump to seals through bird guano.

Currently, four seals are being cared for at the Marine Mammals of Maine’s Harpswell facility. That’s all they’re permitted for, and the other two New England rehabilitation centers — the Mystic Aquarium and the National Marine Life Center in Buzzards Bay, Massachusetts — are also at capacity, Doughty said.

Marine Mammals of Maine, which runs entirely on donations for its operating costs, told NECN that it has already spent its full animal care budget for the year.

Doughty has alerted the fisheries department at the National Oceanic and Atmospheric Administration (NOAA), which governs her organization and grants its permit, about the increase and is now increasing sampling of the carcasses and looking for potential causes.

Doughty asks that anyone who sees a live or dead seal in Maine to call (800) 532-9551.

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