MARSHFIELD (CBS) – They washed ashore on Cape Cod beaches, hypothermic and in danger. Thursday, four loggerhead sea turtles began their journey back to the ocean thanks to the New England Aquarium and rescue volunteers.

This has been one of the busiest winters for sea turtle strandings on Massachusetts beaches. In total, 415 turtles have been treated at the New England Aquarium’s hospital in Quincy. Hundreds have already been moved to other specialized rehab hospitals.

“We don’t have enough space to house these large loggerhead turtles,” the aquarium’s Connie Merigo said in a statement.

The four loggerheads flown out of Marshfield Municipal Airport on Thursday were between 30 and 80 pound each. They were taken to a sea turtle rescue facility in North Carolina to continue getting stronger.

Pilot Paul Schubert deserves special recognition in the effort. The aquarium says he regularly donates his time, plane and fuel to help rescue endangered turtles.