Jacquie Walters, Ed Standora and Andy Harrison
with diamondback terrapins
You cannot help but like turtles.
My own affection and appreciation for them grew out of an early experience. My older brother caught two painted turtles in a swamp near our home and placed them in a cement-sided window box in our yard. Remarkably, one of them climbed the vertical side of that box and escaped. It must have found the minute cracks in that cement with its sharp toenails.
From that experience I could easily appreciate Aesop's story of the tortoise and the hare. The turtle is the perfect living metaphor for stay-the-course.
Thus I was delighted to visit Ed Standora's lab at Buffalo State College to learn about the work he and his graduate students Jacquie Walters and Andy Harrison are doing with spotted turtles here and diamondback terrapins in Barnegat Bay, New Jersey.
For 40 years Standora has been using biotelemetry to study animal activities, working with sharks and alligators as well as turtles.
The local project Walters finished (with Eric Duma) studied rare spotted turtles in Erie and Niagara Counties for the Department of Environmental Conservation. For that study Walters did the Geographic Information System (GIS) work. Her turtles indeed moved slowly: from 4 to 36 feet per day. In fact, she found that the entire annual home range of an individual turtle varies from about a half acre to just over 3 1/2 acres.
Walters' more recent project used biotelemetry to determine home ranges and movement patterns of diamondback terrapins in Barnegat Bay, New Jersey, using different GIS modeling techniques. Diamondback terrapins are handsome freshwater turtles that were driven to near extinction as a former food source. Their status remains "of special concern" in a number of states. They are perhaps best known as the "Terps" for University of Maryland teams.
Surprisingly Walters found that many male terrapins spent time on land. The female terrapins were the real water travelers, sometimes swimming over four miles in a single afternoon. I doubt that Aesop's rabbit could swim that fast.
Harrison holds a diamondback terrapin
(Notice the recording box on its back)
Harrison's project (with Lori Lester of Drexel University) is to determine the impact of boat traffic on the diamondback terrapins in the same Barnegat Bay area. Each terrapin is outfitted with expensive instrumentation that records swimming depths, acceleration, diving angles, and temperature. He has applied mathematical formulas to turtle movement data, treating them as if they were airplanes flying through the water and measuring their pitch (tipping forward and back) and yaw (tipping side to side). He compares their behavior in the presence and absence of boats by recapturing them and downloading the data from the recording devices, which are much like the black boxes in aircraft.
Little was known about how these turtles interacted with motorboats although many captured individuals showed signs of boat propeller injuries. Harrison's preliminary results indicate that the turtles seek by a variety of means to avoid the boats. They swim away from them or dive to the bottom of the estuaries and dig into the substrate. Such activity increases metabolic costs by both interrupting feeding and demanding extra effort. To respond to this, turtles have to increase food consumption at other times in order to maintain normal growth rate.
The implications for wildlife managers, if Harrison's research this summer supports his early predictions, are evident. It may be necessary to identify and establish areas in which boat traffic is restricted and to enforce reduced speed limits in open areas in order to reduce the severity of collisions. Harrison and Standora have already suggested that special boating restrictions should be enforced near nesting beaches during June and July.
The research lab in New Jersey is situated on 200 acres of undeveloped land adjacent to Barnegat Bay. This estuarine paradise and associated fauna are located less than an hour's drive from the casinos of Atlantic City. Much of the work of Standora and his students is supported by volunteers who learn about their projects on the web. Readers can participate in this or other research projects around the world by contacting www.Earthwatch.org.
Wende Mix, a professor in the Geography and Planning Department, has been instrumental in the spatial analysis of this team's movement data. The Earthwatch project director, Hal Avery, a professor at Drexel University, is a Buffalo State graduate.-- Gerry Rising