By Marcia Anderson
The seasonal vehicular migration that we make to the shore coincides with the beginning of diamondback terrapin nesting season in the northeast, often causing hundreds of turtle fatalities. Most of the terrapins that are squashed under car tires are pregnant females looking for a place along the shoulder of the road, above the high tide line to dig their nests and lay their eggs.
Terrapins are relatively small, harmless turtles that live in salt marshes along the Atlantic and Gulf coasts of the United States. They are closely related to freshwater turtles and are the only turtles that are adapted to living exclusively in the brackish waters of coastal salt marshes. Their range extends along the Atlantic coast of the United States from Cape Cod to Southern Texas. The Jersey Shore, Long Island and Staten Island have beleaguered “vulnerable” populations of terrapins. In Massachusetts and Rhode Island, terrapin populations are considered “critically imperiled.”
So What? Why is it important to save terrapins? Terrapins are a predator of periwinkle snails that feed on salt marsh grass. Periwinkles are known to destroy thousands of acres of salt marsh, converting marsh meadows into mudflats. Some salt marshes in the United States have experienced explosive populations of periwinkles due to over-fishing of blue crabs, yet another predator. The destruction of wetland habitats may lead to increased flooding, ultimately affecting coastal property values.
Road Kills: Coastal development has led to considerable terrapin habitat destruction of barrier beach islands and sand dune nesting sites due to the construction of communities and roads adjacent to coastal salt marshes. This results in large numbers of road kills from Memorial Day Weekend through mid July. Female terrapins are killed while attempting to cross roads in search of suitable nesting habitat.
Students from the Wetlands Institute, a part of New Jersey’s Stockton State College, and local volunteer residents conduct road patrols during the terrapin nesting season to minimize the number of road kills of nesting females, as well as the removal of potentially viable eggs from the carcasses of road kills. Collected eggs are incubated and, after hatching, are raised at the institute’s “turtle farm” for at least four months. The young turtles are then weighed, measured and tagged with an embedded microchip and then released back into the salt marsh. This highly successful diamondback terrapin conservation project has been conducted in the salt marshes of the Cape May Peninsula since 1969.
The Wetlands Institute has also initiated “The Barrier Fencing Project,” created to help lessen the number of terrapin road kills of pregnant females looking for alternative nesting grounds. After much experimentation with various barriers and fences, they found that six-inch corrugated plastic drainage pipe was proven to be an effective, inexpensive, and easy way to install a barrier. In June 2010 over 7,000 feet of corrugated tubing was installed. Shortly after, road kills were reduced along the entire length of this new safety barrier.
The take-home message: Terrapins are in serious trouble throughout the coastal northeastern regions of the U.S. and it is up to us to ensure their survival. When you see a terrapin crossing the road: slow down, stop, pick her up, cross her in the direction she was traveling, and wish her good luck. Contact the Wetlands Institute for more information on the diamondback terrapin conservation project: http://wetlandsinstitute.org/conservation/terrapin-conservation/.
About the Author: Marcia is the bed bug and vector management specialist for the Pesticides Program in Edison. She has a BS in Biology from Monmouth, second degree in Environmental Design-Landscape Architecture from Rutgers, Masters in Instruction and Curriculum from Kean, and is a PhD in Environmental Management candidate from Montclair – specializing in Integrated Pest Management and Environmental Communications. Prior to EPA, and concurrently, she has been a professor of Earth and Environmental Studies, Geology and Oceanography at Kean University for 14 years.