The Carlisle Mosquito Online

Friday, April 17, 2009

Blanding’s Turtle study to begin this season

The Conservation Commission (ConsCom) has approved a research project by Concord herpetologist Dr. Bryan Windmiller that could lead to greater understanding of the population dynamics of the rare Blanding’s Turtle. It could also help a Carlisle population survive and grow. Windmiller met with the commission on April 9 to describe his proposed work and the need to learn more about the turtle’s biology.

Windmiller indicated that Blanding’s Turtle is classified as “threatened” in Massachusetts and may soon also be federally listed. There are about 100 populations currently known in the state. Some of these have been studied for more than 35 years.

Windmiller reported that a population in Concord has decreased by half since 1971. Similar patterns have been found at other sites in Massachusetts. A major reason for the decline may be the failure of enough young to mature.

The young hatch in late September. To increase their chances of reaching maturity some hatchlings are now being raised by the New England Aquarium and the Stone Zoo – at least through the first winter until they are too large for smaller predators such as water snakes and grackles. Predators have generally become more abundant.

There are also fewer nesting sites as more land is developed. Blanding’s Turtles take 20 years to reach breeding maturity. Some have been reported to return to the area where they were born to nest. Nests have been found in lawns and under foundation plantings – hardly optimal locations.

The Carlisle population is found partially on town conservation land, thus requiring ConsCom approval for the research project. Windmiller has the required permit from the state. He will mark individuals, radio-track a subset of these, and locate and protect nests. His goals are to determine survivorship and causes of mortality, movement and breeding patterns. The long-term study will begin this spring. ∆

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