WESTBROOK – The shutdown of New England’s largest seal rescue and rehabilitation organization as harbor seals begin having their pups has other organizations scrambling to fill the void.

Seals ordinarily would be barking up a storm at the Marine Animal Lifeline’s nondescript facility outside Portland. Instead, the medical ward where sick and malnourished seals received IVs and the pools where they learned to hunt fish are empty. A red ambulance-style truck used for transporting seals rests outside. The gates are padlocked.

“It’s the worst time of the year for this to happen,” said Dianna Fletcher, chairwoman of the nonprofit’s board.

Last month, the National Marine Fisheries Service abruptly yanked the organization’s permit for releasing 81 seals without testing for a pathogen that causes a contagious distemper-like illness. Twenty-one seals that were being rehabilitated were trucked to the Mystic Aquarium in Connecticut.

“We didn’t have a lot of choice about terminating the authorization,” said Teri Frady, an agency spokeswoman.

Lifeline can seek re-authorization, and its board “seems to have a pretty aggressive attitude about fixing problems,” Frady said.

For now, Lifeline’s absence leaves a void on a busy stretch of coast – midcoast Maine to the New Hampshire border – in the state with the biggest seal population on the East Coast.

“It’s going to be a long season,” said Heather Medic, stranding coordinator for the Mystic Aquarium, one of several institutions across New England poised to take seals from Maine if necessary. Statistics suggest it will be.

Lifeline had a capacity for 70 harbor seal pups and its volunteers responded to hundreds of stranding reports each year.

At its peak, the medical staff and its 200 volunteers responded to 529 seals in 2005. Of those, 253 seals were collected and sent to Westbrook for rehabilitation. Last year, the organization rehabilitated about 200 seals.

No other organization comes close. Mystic Aquarium, by contrast, rehabilitates about 20 harbor seals in a busy year, Medic said.

Geography is the reason.

Maine’s coast is the place where harbor seals come to give birth and nurse their pups, from the middle of May through early June.

The last estimate, from 2001, put the number of harbor seals at 99,340 in Maine, according to James Gilbert, a professor at the University of Maine. That compares to fewer than 10,000 before seals became federally protected in 1972.

With all of those seals, it’s natural that some pups will become separated from their mothers. They often end up on beaches, Gilbert said.

When alerted to seal strandings, members of the New England stranding network assess the situation before either rescuing the seal or waiting and observing. Sometimes the mother comes back for the pup, sometimes not.

Greg Jakush, who founded Lifeline, was bullish on taking in stranded pups sooner than later.

But the Maine Department of Marine Resources is going to be taking a wait-and-see approach over the first 24 hours or more if a seal appears to be healthy.

With fewer resources, it’s especially important to wait to see if the mother will come back for the pup, said Linda Doughty, the DMR’s stranding coordinator and a former animal care technician at Lifeline.

Part of the problem is that seals are cute and people quickly gravitate toward them when they appear on a beach.

Often people see a pup alone and shaking, so they call for help. But the baby seal is usually not shaking because it’s cold or sick but because it’s frightened by the crowd of curious onlookers, Medic said.

“People love seals to death. It’s really very stressful,” she said. “A lot of time, seals die from stress alone.”

Furthermore, a mother seal is less likely to return once a pup has been exposed to humans, Medic and Doughty said.

This summer, seal organizations are redoubling their efforts to warn people to stay away from pups. And volunteers from Delaware, Virginia, New Jersey and Massachusetts stand ready to come to Maine to help with stranded seals.

As for Lifeline, it’s unclear if or when the organization will be reconstituted, but Fletcher said she’s optimistic it will happen eventually. Conversations with the National Marine Fisheries Service are continuing, she said.

The toll-free number to report a stranded seal or other marine mammal in Maine is (800) 532 9551.