NEWS JOURNAL (Wilmington, Deleware) 19 August 03 Fence helps, but turtles still dying - Other solutions sought for Del. 1 south of Dewey (Molly Murray)
Special fences designed to keep diamondback terrapins off a stretch of Del. 1 near Delaware Seashore State Park have helped reduce the number of turtles from being run over this summer, state environmental officials said Monday.
But after three years of monitoring female turtle mortality, officials said a more permanent solution is needed to keep the turtles safe in what they have termed a 1.8-mile "high kill zone" just south of Dewey Beach.
Many female turtles are killed on the highway in June and July after crawling from Rehoboth Bay, across a narrow sand spit, through the salt marsh, and across the highway on their way to the open sand dunes along the ocean beach where they lay their eggs.
State officials now are considering options such as different fencing, creating beach nesting habitat on the west side of Del. 1 so the turtles don't have to cross the highway, or creating passages beneath the road so turtles could swim to nesting areas, said Chris Bennett, a natural resources specialist with the state Division of Parks and Recreation.
"The plan is to try a whole array of options," Bennett said. He said the uncertainty results from the lack of knowledge about turtle populations in Delaware's Inland Bays, and whether they would use new nesting areas or a tunnel system to the dunes on the east side of the busy road.
The state has been trying for several years to protect the turtles.
In the summer of 2001, officials identified the short stretch of Del. 1 north of Old Inlet Bait and Tackle Shop as a big problem area and built a low wooden fence to keep the terrapins on the bay side of the highway. They saw an 11 percent decrease in mortality from 102 dead terrapins in 2001 to 90 in 2002.
But the fence was not entirely successful.
"In fact, what we're learning is that nesting females will do almost anything to get to nesting habitat," said Carrie Houssock, who spent the last two months monitoring turtle movement. "In one experiment, we encircled a female with snow fence and within seconds she had figured out how to turn on her side and slip between the slats."
This year, state officials installed an opaque material on the back side of half of the existing wooden fence, hoping to block the turtle's view of its destination. Studies had shown that if the terrapins were unable to see their destination, they wouldn't attempt to cross the barrier.
"Although it's difficult to tell conclusively if the fabric was effective, the data suggests that it's working," said Alex DeWire, another DNREC worker who helped monitor turtle movements this summer.
Six dead terrapins were found in the area where both fabric and fencing were installed, compared with 35 in the area where there was fencing only, he said.
One option to be studied by the state would involve adding more sand to some test areas on the west side of the highway to see if the turtles would use them as alternative nesting habitats, Bennett said. The turtles prefer sandy areas above the high tide line where there is little vegetation, he said.
But that option may be difficult to implement because there is little suitable habitat for beach nesting on the west side of Del. 1.
And that option shares a problem with the idea of creating a path for the turtles under the road.
"We don't know that they would use it," Bennett said.
Fence helps, but turtles still dying