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(70-66) Effects of trophic uptake of trace elements on banded water snakes (Nerodia fasciata). Hopkins, William*,1, Roe, John1, Snodgrass, Joel2, Staub, Brandon1, Jackson, Brian1, Rania, Lisa3, Sever, David3, Congdon, Justin1, 1 University of Georgia, Savannah River Ecology Laboratory, Aiken, SC2 Towson University, Baltimore, MD3 St. Mary's College, Notre Dame, IN ABSTRACT- Very little is currently known about the accumulation or effects of contaminants on reptiles. To date, most studies examining reptile exposure to trace elements report tissue burdens of field-captured animals, but seldom provide insight into the dose, duration, or mode of exposure involved. For two years, we fed juvenile banded water snakes (Nerodia fasciata) prey items collected from a coal ash-contaminated site containing elevated levels of As, Cd, Cu, Se, Sr, and V. With the exception of Cu, snakes accumulated significant concentrations of elements, usually in a dose-dependent manner. Accumulation varied significantly among liver, kidney, and gonads. Selenium accumulation was most notable, greatly exceeding established toxicity thresholds for other vertebrates. Despite the high concentrations of pollutants accumulated, snakes exposed to the contaminated diet survived through the study and exhibited normal food consumption, growth, over-winter survival and mass loss, metabolic rate, and gonadosomatic index. However, accumulation of trace elements was accompanied by liver histological abnormalities in 30% of snakes ingesting contaminated prey. The results of this study confirm that diet can be a significant route of exposure to trace elements in snakes and indicate that further studies on snakes are warranted to better understand their responses to contaminants. Key words: reptiles, metabolism, trophic transfer, selenium |
