Hester, Joy M.. Effects of relocation on movements and home ranges of eastern box turtles (Terrapene carolina). (Poster Presentation)

Eastern box turtle (Terrapene carolina) populations are threatened by expanding urbanization, the resulting loss of habitat, and the introduction of threats such as roads, railroads, and pets. Individual box turtles are often captured by humans and relocated substantial distances from their capture location. Additionally, relocating populations of box turtles to a less threatening environment has been suggested as a possible conservation strategy. However, previous studies examining the effects of relocation on box turtles are limited. Thus, we compared the home ranges and movement patterns of resident and relocated box turtles. We radio tracked ten relocated and ten resident female box turtles on the Davidson College Ecological Preserve, in Davidson, NC. All turtles were tracked twice weekly during the active season beginning in May 2004. Geographic coordinates were recorded during each tracking session. Results suggest that the majority of relocated box turtles have larger home ranges and move longer distances than resident box turtles. Additionally, relocated turtles had higher mortality and disappearance rates than resident turtles. Our preliminary results indicate that relocated box turtles do not quickly reestablish home ranges in a new habitat, and may attempt to leave their relocation site, thus raising questions about the success of relocation as a conservation strategy for eastern box turtles.

Gooch, Michelle M., Aubrey M. Heupel, Steven J. Price, and Michael E. Dorcas. The effects of survey protocol on detection probabilities and site occupancy estimates of summer-breeding anurans. (Poster Presentation)

Recent global declines in amphibian populations have created an urgent need for largescale, long-term monitoring efforts and many anuran monitoring programs have been established that utilize volunteer-based calling surveys. Calling surveys can be effective monitoring tools; however, differences among survey protocols often bias survey results. Failure to take into account detection probabilities when monitoring anurans can lead to inaccurate inferences about site occupancy, since non-detections in survey data do not necessarily mean that a species is absent unless the probability of detection is 1. We used a likelihood-based method, in the form of the computer program PRESENCE, to estimate detection probabilities and site occupancy rates for summer-breeding anurans. Using detection data from calling-surveys, we evaluated how detectability and site occupancy for 5 anuran species were influenced by 1) time spent listening at each site, 2) number of surveys per site, and 3) sample- and site-specific covariates. We found considerable variation among species with regards to detection probability and site occupancy across time and survey period. Longer surveys resulted in more species detections and increased detection probabilities; 13% of all species detections occurred after 3 minutes. Covariates had differing effects on occupancy and detectability among individual species. Multiple surveys per site within a season that are longer than 3 minutes are necessary to eliminate biased detection probabilities and provide truer estimates of site occupancy. Our results emphasize the importance of evaluating detection probabilities for any long-term monitoring project.

Price, Steven J., Michael E. Dorcas, Alisa L. Gallant, Robert W. Klaver, and John D. Willson. (SJP and MED) Department of Biology, Davidson College, Davidson, NC 28035-7118, (ALG and RWK) USGS/EROS Data Center, Sioux Falls, SD 57198, (JDW) Savannah River Ecology Laboratory, Aiken, SC 29802. Three decades of urbanization: Estimating the impact of landscape change on stream salamander populations. (Oral Presentation)

Recent studies of land cover change in the Piedmont ecoregion of the United States reveal a substantial increase in the amount of urban land cover and a corresponding reduction in forested land. Small streams in the Piedmont support high densities of salamanders and are often the first habitats to be affected by landscape-altering factors such as urbanization. Our objective was to estimate the change in abundance of stream salamanders near Davidson, North Carolina, a Piedmont locale that has experienced rapid changes in land use. We used United States Geological Survey Land Use/Land Cover trend data to quantify land cover changes from 1972 to 2000 within watersheds of small headwater streams. Salamander abundance was calculated using models that allowed predictions of the relative abundances of Desmognathus fuscus and Eurycea cirrigera based on land cover within each watershed. Our analysis suggests that E. cirrigera populations decreased by 30-50% over the last 3 decades and populations of D. fuscus have decreased by 20-35%. Most of our estimated population reductions occurred from 1985 to 2000, which correspond with a significant increase in urban land cover. Our results suggest that accelerating rates of urbanization and other landscape changes near Davidson, NC and throughout the Piedmont have likely resulted in a substantial decrease of stream salamanders. The impacts of such a decline on ecosystem function is unknown.

Dorcas, Michael E. and Charles R. Peterson. (MED) Department of Biology, Davidson College, Davidson, NC 28035-7118, USA; (CRP)Department of Biological Sciences, Idaho State University, Pocatello, ID 83201 USA. The physiology and ecology of the Rubber Boa (Charina bottae) in southeastern Idaho. (Oral Presentation)

Rubber boas (Charina bottae) are small, secretive snakes found in a variety of habitats throughout the northwestern United States. We studied the physiology and ecology of rubber boas in southeastern Idaho over several years in the field using radiotelemetry and mark-recapture techniques and in the laboratory by examining thermal preference and the effects of temperature on whole-animal physiology. Free-ranging rubber boas remain hidden much of the time but may actively thermoregulate to maintain stable, high body temperatures during gestation and digestion. Rubber boas are often nocturnally active at relatively low body temperatures (6-20 C) resulting in low levels of physiological performance. For example, while active at night, rubber boas experience body temperatures that result in performances only 10% to 40% of maximal. Rubber boas may partially compensate for this performance reduction by physiologically reducing the cooling rates of their heads. Mark-recapture studies reveal that rubber boas can be very abundant in some habitats, outnumbering other more frequently encountered species of snakes. However, female rubber boas reproduce on average every three years and have relatively small litters (3-7 babies). The low reproductive rate of this species apparently requires a high rate of juvenile survivorship and a long life span to maintain stable population sizes.