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	Turtles in 2000

Tracking Blanding's Turtles in Central New Hampshire

by Laura Deming

This summer, Audubon biologists spent the first of two field seasons tracking Blanding's turtles in central New Hampshire wetlands to find out where these reptiles go during the course of their active season. This project, which is funded by the U. S. Environmental Protection Agency, is a cooperative effort involving New Hampshire Fish & Game's Nongame and Endangered Species Program, the University of New Hampshire, the Office of State Planning, and the New Hampshire Natural Heritage Inventory Program. Within the overall goal of identifying and protecting wetlands in the southern part of the state, Audubon will be working closely with New Hampshire Fish and Game Nongame biologists to identify and evaluate central New Hampshire wetlands that provide habitat for Blanding's turtles and vernal pool amphibians. (There's more about turtle conservation in our Turtle Conservation Fact Sheet.) Blanding's Turtle Photo by Marquis Walsh, NH Fish & Game Dept. A vast number of species rely on wetlands for all, or part of, their life cycles, including invertebrates, such as dragonflies and whirligig beetles, and vertebrates, such as fish, frogs, salamanders, turtles, some snakes, and many species of birds and mammals. All of them are threatened by destruction and degradation of wetland habitats. Certain species, however, are especially vulnerable to habitat loss, because they have specific habitat requirements or are relatively uncommon. Conservation of these species means identifying and protecting the types of habitats upon which they depend. One species of conservation concern is the Blanding's turtle, one of six native turtles in New Hampshire. Researchers have observed that Blanding's turtle populations have declined dramatically over the past few decades. Although these declines are probably partly due to collecting for the pet trade, the main threat to these turtles is loss of habitat to development. This species spends a great deal of time on land, traveling among various wetlands in search of food. An individual Blanding's turtle may travel several miles over the course of the summer, visiting marshes, beaver ponds, slow-moving streams, and other sites where it can find food. They depend on aquatic habitat for much of their lives, but they also require undeveloped uplands for traveling safely. Upland habitat, especially in the southern part of the state, is rapidly being converted to residential and commercial developments. Remaining areas of undeveloped lands are becoming increasingly isolated from one another by roads, which can present major barriers for turtles and other small, slow-moving wildlife. Blanding's turtles are fairly common in the Midwest, ranging from Nebraska to western New York, and from southern Ontario to central Illinois. Eastern populations are disjunct from those in the Midwest and occur in isolated pockets in eastern and northern New York, eastern New England, and Nova Scotia. Because eastern Blanding's turtle populations are small and very localized, they are especially vulnerable to habitat destruction and human disturbance. Turtle Release Photo by Marquis Walsh, NH Fish & Game Dept. Natural factors also contribute to this turtle's precarious status in eastern New England. Blanding's turtles have a relatively low reproductive rate compared to other species, such as painted or snapping turtles. New Hampshire's cold climate cause turtles to have a shorter active season than turtles have in areas farther south, so they grow more slowly and reach maturity at a later age than individuals in more southern populations. Blanding's turtles in Maine and New Hampshire may not reach reproductive age until they are 12-15 years old, and females may lay only 5-13 eggs per clutch. The loss of a reproductive-aged adult to the pet trade or on the road can severely impact a population, which may consist of just a dozen or so breeding individuals. The objective of the turtle telemetry study is to determine what types of habitats individual adults use over the summer, from the time they emerge from hibernation, through courtship, mating, nesting, foraging travels, until they eventually return to overwintering sites. This information will be the foundation of a habitat model for the Blanding's turtle that can be used to identify important habitat for this species in other parts of the state. It will also indicate how much area a single adult requires, and, perhaps, the area needed to preserve an entire population. Other species that are of concern are those that rely on vernal pools for breeding. Vernal pools are small, temporary wetlands that typically flood and dry on an annual basis. Although vernal pools vary tremendously in size, dominant vegetation, and location in the landscape, they all have one feature in common: they do not support fish populations. For this reason, they provide suitable breeding sites for species that reproduce in relatively low numbers and therefore cannot sustain predation by fish. Certain amphibians, such as wood frogs and spotted, blue-spotted, Jefferson's, and marbled salamanders, are obligate vernal pool species, meaning that they require this type of wetland to breed successfully. Some of these species can be found breeding in more permanent wetlands, but they do not occur in areas where there is insufficient vernal pool habitat. Turtle Radio Tracking Photo by Marquis Walsh, NH Fish & Game Dept. Because vernal pools are often completely dry, they are usually not recognized as important wildlife habitat and may be filled in or otherwise destroyed. Uplands surrounding these pools are also extremely important, as all of the amphibians and many of the invertebrates that breed in the pools actually live in upland forests during the rest of the year. The salamanders that breed in vernal pools are called "mole salamanders" because they live underground in burrows except for the two or three weeks in spring when they are in the pools. Studies have shown that even partial loss of forested habitat around a pool can cause severe declines-and even complete devastation-of wood frog populations. Since wood frog eggs and larvae are important food sources for other species, such as Blanding's turtles, their disappearance from a pool may signal the end of a thriving vernal pool community. Protecting vernal pools and other habitats for reptiles and amphibians can be best accomplished by involving local citizens through education and outreach. The task of preserving and managing ecologically important lands will most often be the responsibility of town planners and private landowners. Over the next year, we will be working closely with the towns of Hopkinton, Dunbarton, and Weare to locate vernal pools and turtle habitats. In order to accomplish what we have set out to do, we will need lots of help, particularly with field surveys for vernal pools and turtle habitat. To this end, we will be conducting workshops and volunteer training sessions for interested individuals early in the spring of 2001. If you would like to help out, or are interested in attending a workshop, please contact Laura Deming in the Conservation Department at 224-9909 and keep your eyes open for upcoming announcements of workshops this spring.