BIDDEFORD — Four months after getting stuck in the icy waters of Cape Cod, five loggerhead sea turtles that spent the winter in Biddeford are headed south for a second lease on life.

The turtles, rehabilitated at the University of New England’s Marine Animal Rehabilitation Center, are part of a “Sea Turtle Trek” that will send 46 loggerhead sea turtles to Jacksonville, Fla., to be released back into the Atlantic.

Those turtles are among the 100 loggerheads that got stunned by cold water and stranded on Cape Cod late last year. The event left experts searching for the reason.

“This year we were off the charts in terms of the number of sea turtles coming in,” said Tony LaCasse, spokesman for the New England Aquarium in Boston.

Marine biologists have no idea why there were so many strandings, but some speculate there could be a connection to the warm temperatures of the winter of 2011-12, LaCasse said.

During the latest stranding season – a roughly six-week period in November and December – the New England Aquarium took in 242 rescued sea turtles, including 100 loggerheads.

In a normal year, the aquarium gets about 70 sea turtles, including five loggerheads.

The influx of loggerheads, which weighed 30 to 100 pounds each, created an immediate need for more space to treat them for hypothermia.

A network of rehabilitation facilities, including the marine center at UNE, cared for the turtles when the New England Aquarium’s Animal Care Center in Quincy, Mass., ran out of space.

Juvenile turtles ride the Gulf Stream to Cape Cod in late June and July to feed on crabs.

Those that fail to leave when the water temperature starts to drop in September often get swept into Cape Cod Bay as they try to migrate south.

As the water temperature continues to drop, the turtles get increasingly lethargic and don’t move around much, LaCasse said.

Suffering from extreme hypothermia, turtles wash up on the shores of Cape Cod. Volunteers from the Massachusetts Audubon Sanctuary search beaches around the clock for stranded turtles, which are taken to the New England Aquarium and other marine rehabilitation facilities.

The Marine Animal Rehabilitation Center took in 14 stranded turtles, starting in December. One died and five remain at the center, while the others were taken to Florida to be released, said Kristen Patchett, the center’s rehabilitation coordinator.

She said loggerheads are considered an endangered species worldwide and threatened in U.S. waters.

The five remaining turtles at UNE – which the staff has named Jawbreaker, 100 Grand, Gobstopper, Pop Rock and Abba-Zabba – arrived in Biddeford in mid-December.

Their weights ranged from 34 to 91 pounds.

Asheley Simpson, an animal care laboratory technician at the marine center, said the turtles likely are 5 to 6 years old and could grow to be 250 pounds.

“They have a lot of growing to do still,” she said.

On Wednesday, Simpson helped weigh, measure and tag the turtles in preparation for their trip south.

One of the tags, similar to a microchip that’s used for dogs, allows researchers to access a turtle’s history from a database.

Working with loggerhead turtles is rewarding because it helps the species grow its population, but it’s “bittersweet” to see them go, Simpson said.

“We just need to get them back out in the wild,” she said. “Hopefully, they’ll live long, healthy lives.”

Gillian Graham can be contacted at 791-6315 or at:

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