Sea turtles nursed back to health after record rescue from cold

By Harriet McLeod

CHARLESTON, S.C., Feb 23 (Reuters) - A veterinarian punched a syringe into the tough, wrinkled neck of an endangered sea turtle named Crowe one day this week at the South Carolina Aquarium and drew dark, red blood to test whether the animal was ready to be sent back into the wild.

The Kemp's Ridley turtle was among the record number of rescued sea turtles stunned by cold water in the U.S. Northeast late last fall. Despite weeks of antibiotics, vitamin injections and fluids, an X-ray revealed Crowe had joint swelling in his flippers and still was not healthy enough for release. Kemp's Ridley is the most endangered of sea turtle species, according to the U.S. Fish and Wildlife Service.

Turtles "beat themselves up in captivity," said veterinarian Shane Boylan, who has been treating the animal at the aquarium in Charleston, South Carolina.

Similar efforts have been underway at 17 aquariums, marine facilities and labs from New England to Florida since more than 200 loggerheads, Kemp's Ridley and green sea turtles fell victim to a pre-Thanksgiving cold snap in otherwise warm waters.

The hypothermic turtles, some of which were emaciated or had pneumonia, initially were brought to Boston's New England Aquarium as part of an unprecedented large turtle rescue by the facility. But the aquarium's turtle hospital is designed to hold no more than 70 animals and was quickly overwhelmed, said Connie Merigo, rescue department manager and senior biologist.

"One hundred loggerheads came in, each weighing 20 to 90 pounds," she said.

The aquarium kept the turtles that were in critical condition and transferred 139 others by van and private plane to various East Coast facilities, she said.


The U.S. Coast Guard flew 35 sick turtles and their medical records on a C-130 transport plane to Florida, where they were divided among several marine facilities.

The South Carolina Aquarium took in 15 sea turtles at its turtle hospital, said Kelly Thorvalson, manager of the aquarium's Sea Turtle Rescue Program. Weeks of treatment followed to reverse the severe effects of cold water stunning.

"Their bodies shut down. Their digestive system shuts down. Their heart rates slow," she said.

Of the 242 sea turtles brought to the New England Aquarium, two dozen were dead on arrival and another two dozen died there, New England Aquarium's Merigo said.

The reason for the record number of cold-stunned turtles remains something of a mystery.

Sea turtles have survived as a species for more than 100 million years and overcome huge odds on their migratory swims over thousands of miles, according to scientists.

Kemp's Ridleys are one of the smallest sea turtles, growing to about 2 feet in length and weighing up to 100 pounds. They nest on the western Gulf of Mexico and range as far as Nova Scotia and Newfoundland. Their population dropped to a critical count of only 702 nesting females in 1985 but government protection has brought the number back to about 20,000.

Atlantic loggerheads, which can live for decades and weigh hundreds of pounds, migrate in a great circle as far as the Azores in the north Atlantic and back to their nesting beaches in the southeastern United States.

Green sea turtles, which grow to be 4 feet long and weigh hundreds of pounds, live and range throughout the world. Their population is threatened mostly by commercial harvesting of their eggs and meat.


They face the risk of drowning in shrimp nets and fishing lines, getting hit by boats or being sickened by ocean pollution. On land, their nesting habitats have been destroyed by coastal development.

Every year, a number of sea turtles get trapped in Cape Cod Bay because the shape of the bay prevents them from swimming south or west without running into land when it begins to get cold. If they swim north, they hit colder water and retreat, New England Aquarium spokesman Tony LaCasse said.

"Instinctively, they might be reacting as a turtle would who is wintering in Georgia and Florida, when you have a cold snap, hunker down and ride it out," he said. "That won't work here."

After a very mild previous winter, a greater number of turtles might have wintered in the Gulf Stream off Massachusetts and then lingered too long closer to shore in the fall, Merigo said.

Overall warming sea surface temperatures may also be affecting the cold-blooded reptiles' cues to migrate south, Boylan said.

"There's no one clear signal for any animal," he said. "Temperature, daylight, electromagnetic fields, they go on what they've got. Sea surface temperatures are changing. The waters are warming up."

Turtles and other animals migrate based on environmental cues that include number of hours of daylight and water and air temperature. Scientists believe sea turtles' migration also follows the lines of the earth's magnetic field.

All 15 turtles transported to South Carolina are expected to recuperate and be released over the next two months, Thorvalson said.

New England's 45 remaining turtles will be released from beaches farther south than Boston this spring, according to Merigo.

"People have this fascination with turtles," LaCasse said. "They identify with struggle and heroically coming back. Hundreds of people come to the beach to watch them released. These turtles, on that release day, are rock stars." (Editing by Colleen Jenkins; and Jeffrey Benkoe)