It's shaping up to be a bad year for turtles.
For the past two years, the number of diamondback terrapins killed on Cape May County roads has increased - and researchers want to know why.
Road kills shot up nearly 51 percent from 2007 to 2008, according to statistics from the Wetlands Institute in Middle Township. So far this year, turtle deaths are on pace with last year's 575 documented road kills.
Almost halfway through a six-week spring nesting period, 269 turtles were crushed by cars along 40 miles of local roads patrolled by the nonprofit Wetlands Institute, which researches and keeps detailed records of road kills.
"We're sort of the middle of the season, so I'm not sure what the ultimate outcome is going to be," said Roger Wood, director of research at the Wetlands Institute.
The terrapins - who have the unfortunate inclination to lumber across roads bustling with seashore traffic - tuck their heads and legs when they sense the danger of a fast-approaching car. Each spring, hundreds of pregnant turtles are crushed in Cape May County on their quest to lay eggs on high land, which is often a coastal road embankment.
Wood and researchers, which include summer college interns, are trying to solve the perplexing problem.
"We're trying to figure out what factors might cause it, but we're not making any really good progress," he said.
Fencing along causeways - including Stone Harbor Boulevard and Avalon Boulevard - has drastically reduced road kills in those specific areas, Wood said.
Elsewhere, turtles have not been so lucky.
There are a number of possibilities.
There may simply be more turtles. For years, conservationists have incubated eggs from dead turtles and released the young turtles into the salt marshes. A student researcher will explore the size and range of recent road kills, Wood said, to determine whether more small and young turtles are being killed.
It may be the weather, which has been especially wet this year. The amount of rainfall in June is more than double the normal, according to the National Weather Service; however, the number of road kills shot up dramatically last year when it was drier, Wood said.
What about traffic?
Last year, researchers repeated an experiment from four years prior to monitor traffic along a stretch of Stone Harbor Boulevard, a popular spot for nesting terrapins.
Wood said traffic hadn't changed much.
"We found that a vehicle would pass by once every four seconds one direction or another," he said. "On weekends or holidays, a vehicle went by ever 2 seconds. We did a little calculation: The odds of a terrapin getting across the road in that circumstance is pretty close to zero."
Pregnant terrapins are charged with a daunting task. Each year, females leave the marshes to lay their eggs on high land. Decades of development on dunes and barrier islands destroyed much of the terrapins' habitat, and now they nest in the embankments of coastal causeways.
This year, some terrapins avoided the roads altogether, building 14 nests and laying 145 eggs in the clay-like surface of a few Central Avenue tennis courts in Sea Isle City.
City residents Susan and Steve Ahern, who noticed the unique tennis-court habitat, help turtles when they can - sometimes helping them across a road.
"We've taken over so much of their habit, I feel like we kind of owe it to them to do what we can," Susan Ahern said.
They are also fascinated by the turtles.
"To stand there and watch how they manage to dig their nests and cover it up - they use their back legs and feet like hands. They're so powerful," she said.
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