The endangered Kemp-Ridley turtles washed up on the beaches of Wellfleet, Mass., on the cape Wednesday night, New England Cable News reported.
"We've actually had 15 sea turtles come in and six more are waiting to be driven up from the cape," aquarium spokesman Tony LaCasse said Thursday.
The turtles come north to feed on crabs during the summer, and many find themselves stranded in the chilly waters of Cape Cod Bay, LaCasse said.
"Sept. 1 it's 70 degrees, Oct. 1 it's 60 degrees, Nov. 1 it's 50 degrees and at that point they're really just floating out in the water," he said.
"This group as a whole really concerns me," aquarium Rescue Rehab Director Connie Mergio said.
All of the turtles are suffering from hypothermia, many have bacteria and algae growing on their bodies, and most are also dehydrated and will likely be diagnosed with pneumonia, she said.
They join 34 other turtles brought into the Boston aquarium's Animal Care Center since Oct. 20.
The aquarium treats as many as 150 cold-stunned sea turtles in a typical year, NECN reported.
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