Monday, November 4, 2013

Giving Turtles a Head Start

By Alix Morris

Why did the turtle cross the road? The original theory for the declining Blanding’s turtle populations in urban areas was that adult turtles were run over by cars. When biologist Dr. Bryan Windmiller and his colleagues began tracking turtle populations in Massachusetts, they found this was not the case. Survivorship of adult turtles was actually quite high. Instead, they encountered a different problem – there were very few young turtles, and almost no hatchlings.

In the wild, under any conditions, turtle eggs and hatchlings are susceptible to a variety of predators, including chipmunks, herons, frogs, and raccoons. When Blanding’s turtles hatch, they have soft and flexible shells for the first year of their life, which offer little protection.

Moreover, hatchlings who are able to survive don’t eat from the time they hatch in the late summer or early fall until the following spring. As a result, they can lose weight during their first six months, further jeopardizing their potential to survive.

“If it’s possible to do something for these guys before they grow, we might be able to help them,” said Windmiller.

Great Meadows National Wildlife Refuge in Concord, Massachusetts has the state’s third largest population of Blanding’s turtles. Yet over the past 40 years, the population of turtles has declined by more than 50%.

In 2003, Windmiller launched a trial method to protect the endangered turtles through the Great Meadows Blanding’s Turtle Conservation Program. Windmiller and his team of volunteers would collect the hatchlings and transfer them to schools, zoos, and aquariums across the state to monitor their feeding and care for nine months – a process Windmiller calls “headstarting.”

Through the headstarting program, the turtles are kept in warm water, which increases their appetite and helps them to grow. The students and researchers who monitor them feed them twice daily.

In captivity, the turtles grow at a rate four times what they would do in the wild. By the end of nine months, they are as large as four-year-old turtles with hard shells. They are then released back into their original habitat. Headstarting increases the survival rate of turtles by 20 times that of wild turtles.

Not all researchers agree with the headstarting program, however.

“Among biologists there’s a divide between people who more readily accept the idea that in the 21st century, if you’re interested in helping to maintain populations of rare and vulnerable species in parts of world where human impact is high, you need to intervene,” said Windmiller. “There are some biologists who are comfortable with that and some who are less comfortable.”

Windmiller hopes that as new and better data comes in from the headstarting project, they will be able to show that not only are they stopping the decline of turtle populations, they are actually reversing it.