CONSERVATION OF DAVIDSON'S AMPHIBIANS AND REPTILES:
HISTORICAL AND CURRENT PATTERNS
Michael E. Dorcas
Davidson College
Over the last few decades, many amphibian and reptiles have experienced dramatic declines, both in the United States and worldwide. Because amphibians and reptiles are often susceptible to environmental degradation, the status of herpetofaunal diversity is likely to reveal the environmental well being of a habitat as well as the consequences of habitat destruction or other forms of environmental deterioration. Documentation of biodiversity is the first step in sound management of animal populations and comparisons with historical distributions allow interpretation of distributional changes over time. The objective of this project is to document the diversity, distribution, and status of amphibians and reptiles in the vicinity of Davidson, NC and to interpret these data in a historical context.
To document the diversity of amphibians and reptiles near Davidson, I will establish monitoring sites both on and off campus. Study sites have already been selected in the cross-country trails area of campus and several ponds on private property near campus have been surveyed for possible use in the study. Because of the clandestine nature of most species of amphibians and reptiles, a variety of survey and trapping techniques are necessary to adequately sample local amphibian and reptile populations.
On the Davidson campus, we (my students and myself) have already set out coverboards (artificial cover) which are checked frequently for resident herpetofauna and we have set up drift fences equipped with pitfall traps to sample local species of amphibians and reptiles. Other techniques we have begun using include turtle traps to sample turtle populations in local ponds and the use of automated recording systems for monitoring frog and toad populations. Expansion of our sampling for other species of amphibians and reptiles in the Davidson Area requires additional resources and information on historical distributions of amphibians and reptiles in the Davidson Area. For example, one of the field sites we have been sampling is a historical site for Bog Turtles (Clemmys muhlenbergii), a federally endangered species that requires protection throughout its range. We hope to find that Bog Turtles are still resident at this site, but more sampling is required.
For each capture/observation, we will record the animal's locality with a global positioning system. These data will be incorporated into a relational database and combined with spatial data (topographic data, satellite imagery, etc.) in a geographical information system (GIS; ArcView 3.1, ESRI). Historical distributional data will be collected from the North Carolina Museum of Natural Sciences (in Raleigh), digitized and incorporated into the GIS for analysis. Collecting historical data from the museum will require several trips to Raleigh to verify species identifications and to record data not yet entered into their databases. The director of the museum, Dr. Alvin Braswell, has agreed to help in any way possible.
In addition to the immediate information gained about historical changes in animal distributions, long-term results of this study will be important to future conservation efforts in the Davidson area. Publications of my own and my students resulting from this project will include peer-reviewed journal articles in addition to popular articles.