Friday, December 30, 2011

Unusual turtle stranding season putting aquatic care center to the test

December 30, 2011

QUINCY — Juggernaut, a 55-pound loggerhead turtle, poked his head out of the water in the pool at the New England Aquarium Animal Care Center. He stretched his neck and snapped a piece of filleted herring from a pair of forceps.

Large white scars, where skin had been peeled back to bone, covered most of his head. Similar wounds marred portions of his shell and his large front flippers. Sometime in early December his metabolism ground to a halt, shut down by cold water temperatures. He floated at the mercy of the wind until washing ashore on a bayside Orleans beach on Dec. 11.

Aquarium staff theorized that Juggernaut's wounds may have come from being bashed around on rocks or other underwater obstructions as he neared shore. Still, he was luckier than most of the turtles who lingered too long in Cape Cod Bay waters this year. Massachusetts Audubon Society figures show that 35 to 40 percent of turtles recovered this year were alive, compared with 45 to 50 percent last year. And fewer were recovered. A total of 129 turtles came in for treatment at the center last year, with only about 40 this year.

Most turtle strandings happen on the Cape and a high percentage of those turtles are Kemp's Ridley, the most endangered sea turtle in the world. Over the past 20 years, the aquarium has rehabilitated and released more than 800 sea turtles. Five of the seven sea turtle species are listed as endangered by the U.S. The five all are occasional or regular visitors to Cape waters.

Aquarium spokesman Tony LaCasse said one theory posits that Kemp's Ridley, the smallest of the sea turtle species, may get caught in localized currents along the Outer Cape in the summer and are swept into Cape Cod Bay.

With land on virtually three sides of the bay, some may find it impossible to find their way back out, LaCasse said.

Unseasonably warm temperatures this year delayed the onset of turtle-stranding season, which usually begins after Halloween and reaches its peak at Thanksgiving. As of early December, only eight turtles had arrived at the care center, as opposed to 108 at the same time last year.

"They've found a lot of long-dead turtles. (Some) are decomposed, and that is unusual," La-Casse said.

It might seem counterintuitive, but an early cold snap that immobilizes turtles, forcing them to the surface, combined with steady winds pushing them shoreward is probably the best thing that could happen to tropical turtles who linger too long in Cape Cod Bay.

"They still have body fat, and no pathogens," LaCasse said.

With record warm weather continuing through most of the fall and into the first week of winter, bay waters remained warm enough that many turtles tried to wait out the cold, hunkered down on the bottom. They burned through their reserves of fat and became susceptible to diseases.

While many of the 34 turtles being treated in the aquarium's care center look to be in better shape than what they typically see this time of year, their blood tests revealed more internal infections.

"They are a little sicker," said aquarium biologist Kerry McNally.

LaCasse estimated the aquarium's marine animal rescue operations cost between $300,000 and $500,000 annually, paid mostly by admission fees to the main exhibition building in Boston. With more attention paid to protecting nesting sites, reducing fishing impacts and rescue of injured animals, some turtle populations are showing signs they are rebounding.

That's why the aquarium decided to invest in its new care center, which focuses mostly on turtle rehabilitation, LaCasse said.

In one of the labs of the 5,500-square-foot facility located in the old Fore River Shipyard in Quincy, McNally and senior biologist Katie Pugliares checked turtle vital signs and weight, took blood samples and cleaned wounds. The goal was to get turtles swimming and eating on their own.

These turtles are solitary creatures and generally don't play well with others.

"As they eat, they get bigger and more aggressive," McNally said. Typically, healthy turtles are moved to Southern aquariums for release.

But slower progress this year fighting infections will likely delay their release until spring or summer.

Photo: Kemp’s Ridley turtles rescued from the cold on Cape Cod beaches swim in tanks at the New England Aquarium Animal Care Center. -- Cape Cod Times/Christine Hochkeppel

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