Diamondback Terrapins Focus of Barnegat Bay (Via HerpDigest)

Diamondback Terrapins Focus of Barnegat Bay (NJ) Study

Wareton, NJ (AP) August 29, 2010- A blend of science, conservation and technology goes into an ongoing 20-year study of diamondback terrapins and the conditions affecting their mortality.
"Overall we are extremely pleased with the progress of this study," Drexel University Professor Hal Avery said. "Our students are working on many diverse projects."

Avery heads the 20-year university study, which is based at the Lighthouse Environmental Center in Waretown and involves the section of the E.B. Forsythe National Wildlife Refuge off Barnegat Bay.
In its fifth year, the project includes studies of turtle migration patterns, population and spawning and is funded by Earth Watch of Maynard, Mass.

Avery said volunteers this year came from the United States, Japan, Canada and Britain. On Friday, the team came across one of the hazards faced by terrapins: a commercial crab trap.

"We call it a ghost trap as it has broken off from a number of traps and was found floating in the bay. These traps could kill terrapins that climb inside it and drown," Avery said.

Ironically, a crabber reported that morning finding a crab trap containing a terrapin that had been tagged for study.

Avery and team members Abby Dominy, a Drexel University graduate student, and Lise Theriault, an Earth Watch volunteer from New Brunswick, Canada, went off by boat to meet up with team members in another boat who were investigating the crabber's find.

The adult female terrapin was alive and well with the three other researchers: Dr. Edward Standora of the Department of Biology, Buffalo State College, Buffalo, N.Y., Julianne Winters, a Drexel University doctoral student who has been with the project for three years, and Earth Watch volunteer Ellen McKnight of New York City.

"They had been looking for that turtle for several weeks," Avery said.

The crabber who alerted them had seen the small orange transmitter antenna that was attached to the turtle's shell bobbing in the water in the crab trap. Standora designed the radio units used to track the turtles.

"There are all sorts of debris from recreation and commercial crabbing," Avery noted. "It creates a potential hazard for them."

Winters said she is studying the impact of bulkheading, which often blocks turtles seeking to return to the area where they were hatched. As part of her studies, she blocked an area and observed their behavior.

"They are spending more time moving around and are then facing more risk," Winters said.
Avery and his team then met up with another team in a bay salt marsh area where Drexel student Lori Lester was using a sonic telemetry device that plays recorded boat engine sounds.

"By measuring their neuro activity, we discovered they can hear, and that was exciting," Lester said.
This summer, her tests demonstrated that turtles placed in a small trench in the marsh did not respond to recorded boat sounds.

"There was no reaction. They just swam right past the speaker. If it were an actual boat in its path, the turtle could have been killed."

Assisting Lester were Drexel University graduate student Elise Winterberger of Bucks County, Pa., and Earth Watch volunteers Eileen Bayer of Maine and Rachel Seary of Wales. They were using a sensor that measures temperature and depth readings.

Avery celebrated his 50th birthday last week with his colleagues, students and volunteers at the Lighthouse Center.

"We really are a family here, and it's fascinating to see the progress of our Ph.D. students who have graduated and who have become full investigators," he said.