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About The Diamondback Terrapin Nesting Survey

Diamondback Terrapins are the only salt water turtle which is indigenous to our saltmarsh habitats. Unlike the larger sea turtles which migrate great distances during the year, the Diamondback Terrapin spends its entire lifecycle laying, hatching and hibernating in the same saltmarsh. Once valued as a human food source, they are now considered a threatened species. We study these turtles in Flax Pond and at West Meadow Beach as part of an effort to assess the health of local terrapin populations. Our goal is also to bring in community members so that they can help protect our natural world.

The Diamondback Terrapin Nesting Survey begins at the middle of June and continues through the end of July. Terrapins nest during the day with peak activity around high tides. Researchers and volunteer citizen scientist patrol the beaches during this time to make counts and collect data on the turtles and their nests.

2006 was the first year we conducted the Diamondback Terrapin Survey at West Meadow Beach and Flax Pond. We were able, as a result of walking the beaches during the nesting cycle, to determine where, at both sites, the turtles are most likely to nest. We also learned more about when the turtles are most likely to appear and how to coordinate accordingly.

A Turtle Hides From Volunteers
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Female turtles swim ashore on the high tide and then nest in the High Marsh. Their eggs have been fertilized by encounter with the smaller males in the water prior to laying. Females Diamondbacks, like other sea turtles, tend to return year after year to the same beach for nesting.


The following is a general description of the work volunteers will do to help in the project

  1. This first step is perhaps the most important because it involves observing the turtle without the turtle's awareness of being observed. Diamondbacks have been known to continue their nesting activity if unnoticed or ignored by passersby. However, the terrapins are hyperaware of the potential presence of perpetrators and have a keen sense of when they are watched, often stopping in the middle of digging a nest and moving off to another location. As a result, "test nests", disturbances in the sediments, can be identified at nesting sites. Once the eggs are laid, the terrapin covers the nest so carefully it can be impossible to identify. Thus the scientist observing a nesting turtle must remain hidden from the turtle's awareness but also be alert to the moment she has finished covering her nest.

    A Turtle Covers A New Nest
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  2. The next step is to very quickly approach the nest before the turtle has left it (or it may be otherwise difficult to impossible to find), and mark it with a flag.

    A Turtle By A Flagged Nest
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  3. Then catch the terrapin who is now setting off back to the water she came from, weigh, measure, and record her data on a sheet numbered to correspond with the number assigned the nest flag.

    Volunteers Receive Instuctions On Recording Turtles
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  4. After releasing the turtle, some nests are protected by a wire cage to try to prevent predation, most likely by raccoon.


When nests are predated, it is possible afterwards to find turtle eggshells scattered about the excavated nest. In this fashion, new nesting sites in can be identified. Late in the season 2006, a predated nest identified a new site for researchers. A protected nest at another site in Flax Pond was not predated. Four caged nests at West Meadow beach were also protected from predation.

Newly Laid Eggs That Will Be Protected From Predation
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If you wish to participate, email us at ebkurtz+terrapins@gmail.com

Friends of Flax Pond, P.O. Box 2112,
Setauket, N.Y. 11733 631.941.9404