PETERSON, J.D.; WOOD, M.B.*; HOPKINS, W.A.; MENDONCA, M.T.; Auburn University; Auburn University; Virginia Polytechnic Institute and State University; Auburn University: Inter-specific differences between larval American Bullfrog (Rana catesbeiana) and Southern Leopard Frog (Rana sphenocephala) susceptibility to Batrachochytrium dendrobatidis infection within a contaminated wetland on the Savannah River Site, South Carolina

Although numerous amphibian populations, world-wide, have been drastically affected by chytridiomycosis, a fungal disease caused by Batrachochytrium dendrobatidis, authors have suggested that some populations may support the presence of this disease without noticeable long-term effects. For the past 25 years, amphibian populations native to the Savannah River Site (SRS), South Carolina have not experienced any drastic population decline events though chytridiomycosis was documented in three adult individuals (two American Bullfrogs, Rana catesbeiana and one Southern Leopard Frog, R. sphenocephala collected there in the late 1970s and early 1980s. Given that so little is known about chytridiomycosis presence within populations at the SRS, we conducted a field survey to identify whether chytridiomycosis is still present within these intensively studied populations. In the summer of 2004, R. catesbeiana and R. sphenocephala tadpoles were collected from three wetlands (2 of which have heavy metal contamination and one without) on the SRS. Batrachochytrium dendrobatidis infection was identified in 62.5% of the R. catesbeiana tadpoles sampled and histologically assessed (N= 50) from a site contaminated with mercury and copper. None of the R. sphenocephala tadpoles sampled (N= 50) were infected regardless of sample site. These data suggest that B. dendrobatidis is still present in some wetlands of the SRS and capable of infecting amphibians. The data also suggest some species may be more susceptible to this infection than others.