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StephF
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Can young turtles make a big change? By LAURA MOYER Fredricksburg FreeLance Star
CHARLES CITY--Nic Frederick found the first box turtle about where he'd expected, eating a mushroom next to a hollowed-out tree. The second nestled in some wet brown oak leaves, a blood-gorged mosquito on its tail.
The next seven turtles were roughly where Frederick expected them to be, hanging out at swamp edges or hiding in tall grass, having moved only a few yards from where Frederick had tracked them the day before.
But the last turtle, No. 204, was a traveler.
Since its release from captivity a couple of weeks before--along with the other nine--this rambling turtle had crossed a road and crawled hundreds of feet along a mostly flat section of forest.
Frederick tracked it as he had the others, using an antenna that picked up signals from a transmitter affixed to the turtle's shell.
Frederick, a 25-year-old Virginia Commonwealth University biology grad student, has been studying Eastern box turtles for the past year and a half at VCU's Rice center, a 340-acre woodland preserve along the James River about 25 miles east of Richmond.
The creatures are appealing, with helmet-shaped carapaces and mellow demeanors that place them among Virginia's most beloved reptiles.
But they're are also in trouble. And Frederick wants to help.
Eastern box turtles, Terrapene carolina carolina, can live to about the same age as people, but they're slow to reach sexual maturity. And when they do reproduce, it's often only one clutch of three or four eggs per year. Juvenile turtles are highly susceptible to predators, and only a small fraction survive to adulthood.
"If a population like this gets hit by anything," Frederick said, "it's hard to bounce back."
What's hit box turtles is us.
Development has destroyed much turtle habitat and fragmented even more. The simple act of constructing subdivision roads cuts the turtles' breeding territory into tiny wooded islands.
Crossing those roads is more than risky. And yet the turtles try, with predictable results.
In addition, box turtles are popular pets, and they're often plucked from the wild by people who think the removal of just one can't hurt. It can, and it does.
Virginia's box turtle population has been in decline for at least 30 years, Frederick said. They're just not able to reproduce as fast as they're being lost. And in some places scientists have identified "ghost populations," concentrations of mature resident turtles, but almost no juveniles.
Efforts to help out by physically transplanting breeding-age box turtles have been disappointing. Like people, the turtles know where home is, and that's where they want to be.
Rather than adapt to a strange location, turtles will simply head back to where they hatched. Their journeys are so purposeful they may not even stop to eat along the way.
That's where Frederick's research project comes in. Is it possible to move turtles still too young to breed, before a particular territory has become imprinted on them as home?
He's studying two groups of turtles that have spent their early lives in captivity. (They are the descendants of 35 adult turtles rescued some years ago from a construction site.)
Those captive-reared turtles are being introduced at the Rice Center, in Charles City County, with the hope that they will thrive there and add their genes to a known resident population.
Frederick tracks his study turtles several times a week and plots their locations using a GPS.
One cool, cloudy summer day he walked through the woods with helpers Kevin Gallagher, 27, who's doing an independent field study for an undergrad class, and Joey Thompson, a 17-year-old St. Christopher's School intern.
Over 2 hours, they tramped up and down ravines, through mud and over logs to track the turtles. Once they found them, they simply noted their positions and moved on--without unnecessarily handling the animals or disturbing their immediate surroundings.
So far, Frederick said, the turtles seem to be doing well. "There are raccoons out here, and one of these guys has been gnawed on," he noted. But there's been little study-turtle mortality.
And along the way, Frederick said, he's come across 41 resident box turtles. They're not part of his study, but he does weigh them and measure the height, length and width of their carapaces, or upper shells, and plastrons, the flat underparts.
He provides that data to the nearby office of the Virginia Department of Game and Inland Fisheries, which also runs box turtle studies and education programs at the Rice Center.
Box turtles, Frederick said, are important to the cycle of life in the woods. They eat anything and everything--worms, insects, fruits, berries, carrion and fungi. They're believed to be important in dispersing fungi spores.
"They play more of a role than just being cute in the forest," Frederick said.
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