Oral Abstract Details

Author(s):
JR Courter, TD Surasinghe, RF Baldwin, RJ Johnson

Affiliation:
Clemson University, Department of Forestry and Natural Resources

Presentation Type:
Oral

Topic Area:
Monitoring and predicting human influences on landscapes and ecosystems

Abstract Text:
Housing development has been linked to loss of biodiversity but assessment over large areas has been difficult. GIS technology has been recently used, however, to identify areas that face environmental risk associated with development. Our study focused on an eight-country region in upstate South Carolina that harbors important bird and amphibian species and is experiencing a high degree of developmental pressure. We produced two models in our study: 1) a threat analysis based on developmental pressure, habitat preference of focal species, and management authority of the landscape and 2) a range reduction model based on developmental pressure, percent of each species range protected in our study area, and the ability of species to resist disturbance. We selected two bird (Eastern Towhee-Pipilo erythrophthalmus and Swainson’s Warbler- Limnothlypis swainsonii) and two amphibian species (Upland Chorus Frog-Pseudacris feriarum and Shovel-nosed Salamander- Desmognathus marmoratus) as focal species, with each pair consisting of a broadly- and narrowly-distributed species. We used 2000-2008 census data to project the growth rate of housing units for the ten-year period (2000-2010), and used this trend to estimate developmental pressure for 2020 and 2030. We reclassified distribution maps from the SC GAP project to reflect habitat preferences of our focal species and reclassified wild lands to reflect the degree of protection provided by different management authorities. Threat analysis indicated that the north-central region of our study area faced the greatest threat for all four species because of increases in housing units and limited protection provided. The northernmost region of our study area, located within the Blue-ridge ecoregion, faced the least threat because of its high degree of protection by federal and state authorities. Projected range reductions for amphibian species were similar, with Upland Chorus Frog negatively affected by development in unprotected habits and Shovel-nosed Salamander negatively affected by an inability to adapt to human development. Between bird species, projected range reduction for Swainson’s Warbler was greater than that of Eastern Towhee because of its high susceptibility to development pressure. Our results showed that narrowly distributed species had a greater percentage of their ranges protected, yet faced increased threats because of their inability to tolerate human disturbance in rapidly expanding urban areas. Species with similar proportions of their range protected and a similar ability to respond to disturbance, may serve as surrogate species to predict species declines in response to development pressure. We suggest using a threat analysis in conjunction with a simple range reduction model that accounts for biological responses of species, can help identify and compare species at risk from housing development.