Ecological Archives A025-141-A1
Elizabeth B. Harper, David A. Patrick, and James P. Gibbs. 2015. Impact of forestry practices at a landscape scale on the dynamics of amphibian populations. Ecological Applications 25:2271–2284. http://dx.doi.org/10.1890/14-0962.1
Appendix A. Additional details of study site characteristics for experiments conducted as part of the land-use effects on amphibian populations (LEAP) project.
Although the experimental arrays were similar at each LEAP site, the geographic differences among the three study regions were substantial. The Maine arrays, located at the University of Maine Demeritt and Penobscot Experimental Forests in Penobscot County consisted of mixed coniferous-deciduous forest in a landscape characterized by low-lying forested wetlands surrounded by well-drained uplands (Patrick et al. 2006). The arrays at this site were centered on vernal pools that dry infrequently, but did not dry during the course of the study. In Missouri the arrays were located in the Daniel Boone Conservation Area, Warren County, in second growth oak-hickory forest on hilly terrain with relief ranging from 46–76 m (Rittenhouse and Semlitsch 2007, Rittenhouse et al. 2008, Rittenhouse et al. 2009). Breeding pools at this site were 40-year-old wildlife ponds that dry only in extreme drought years. The South Carolina arrays were located in Barnwell County at the Department of Energy’s Savannah River Site in forest dominated by loblolly pine (Rothermel and Luhring 2005, Todd and Rothermel 2006, Todd et al. 2009). Here the arrays were centered on shallow Carolina Bay wetlands that dry annually. Among the three sites, climate patterns differ considerably, including the length of the growing season which is typically 131 days in Maine, 177 days in Missouri and 183 days at the South Carolina site (National Climatic Data Center data set 9712C; http://cdo.ncdc.noaa.gov/cgi-bin/climatenormals/climatenormals.pl). The amphibian fauna at each site also differs. Maine’s amphibian fauna is characterized by low diversity but high abundance, with R. sylvatica, A. maculatum and R. clamitans accounting for the majority of drift-fence captures (Patrick et al. 2006). Amphibian diversity was higher at the Missouri site (14 species), and was dominated by ambystomatid salamanders (A. annulatum and A. maculatum) (Hocking et al. 2008). In the South Carolina arrays, amphibian diversity in the terrestrial habitat was high, but many species did not use the central pool for reproduction. Drift fence captures at this site were dominated by Bufo terrestris (Todd and Rothermel 2006) and Scaphiopus holbrooki, but included over 25 amphibian species (Todd et al. 2009). Despite strong ecological contrasts among the study regions, amphibians that responded to the cuts exhibited the same broad trends across regions, with clear-cuts typically resulting in reductions in survival and partial cuts generating either neutral or positive responses (Semlitsch et al. 2009).
Literature cited
Hocking, D. J., T. A. G. Rittenhouse, B. B. Rothermel, J. R. Johnson, C. A. Conner, E. B. Harper, and R. D. Semlitsch. 2008. Breeding and recruitment phenology of amphibians in Missouri oak-hickory forests. The American Midland Naturalist 160:41–60.
Patrick, D. A., M. L. J. Hunter, and A. J. K. Calhoun. 2006. Effects of experimental forestry treatments on a Maine amphibian community. Forest Ecology and Management 234:323–332.
Rittenhouse, T. A. G., E. B. Harper, L. R. Rehard, and R. D. Semlitsch. 2008. The role of microhabitats in the desiccation and survival of amphibians in recently harvested oak-hickory forest. Copeia 4:807–814.
Rittenhouse, T. A. G., and R. D. Semlitsch. 2007. Post-breeding habitat use of wood frogs in a Missouri oak-hickory forest. Journal of Herpetology.
Rittenhouse, T. A. G., R. D. Semlitsch, and F. R. I. Thompson. 2009. Survival costs associated with wood frog breeding migrations: effects of timber harvest and drought. Ecology 90:1620–1630.
Rothermel, B. B., and T. M. Luhring. 2005. Burrow availability and desiccation risk of mole salamanders (Ambystoma talpoideum) in harvested versus unharvested forest stands. Journal of Herpetology 39:619–626.
Semlitsch, R. D., B. D. Todd, S. M. Blomquist, A. J. K. Calhoun, J. W. Gibbons, J. P. Gibbs, G. J. Graeter, E. B. Harper, D. J. Hocking, M. L. J. Hunter, D. A. Patrick, T. A. G. Rittenhouse, and B. B. Rothermel. 2009. Effects of timber harvest on amphibian populations: understanding mechanisms from forest experiments. BioScience 59:853–862.
Todd, B., and B. B. Rothermel. 2006. Assessing quality of clearcut habitats for amphibians: Effects on abundances versus vital rates in the southern toad (Bufo terrestris). Biological Conservation 133:178–185.
Todd, B. D., T. M. Luhring, B. B. Rothermel, and J. W. Gibbons. 2009. Effects of forest removal on amphibian migrations: implications for habitat and landscape connectivity. Journal of Applied Ecology 46:554–561.