PETERSON, J.D.**; ASHE, V.A.; MENDONCA, M.T.; Auburn University; Auburn University; Auburn University: Sublethal effects of coal combustion residues on Southern Leopard Frog (Rana sphenocephala) growth and corticosterone content throughout metamorphosis

Coal combustion residues (CCR) have become a major global pollutant due to increased usage of energy derived from coal burning power plants. 57 million tons of CCR, containing high concentrations of contaminants, are released into aquatic settling basins each year. Numerous organisms, including anurans, inhabit these basins and wetlands, which puts them in close contact with CCR contaminated substrates. Previous research has shown that CCR pose major threats to wildlife and their natural environments due to the large amounts of trace elements (As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Se, Sr, V and Zn) found in water, sediments, and biota from CCR disposal systems. While chronic exposure to CCR is not always lethal, it has been shown to have a detrimental effect on development and morphology in larval anurans. In the current study, Southern Leopard Frog (Rana sphenocephala) tadpoles were exposed to CCR substrates throughout metamorphosis and effects on growth and developmental rate, oral morphology, and corticosterone content were determined. Tadpoles exposed to CCR took significantly more days to complete metamorphosis and hind and forelimb development and weighed significantly less upon completion of metamorphosis when compared to control tadpoles. We also found significantly more oral malformations in tadpoles exposed to CCR. These malformations varied in severity from loss of the most anterior tooth row to loss of all tooth rows and the anterior jaw. Whole body corticosterone content will also be reported. Changes in larval growth, developmental rate, malformations, and corticosterone content may provide insight into the impact these stressors have on key bottleneck events in anuran life history.