Date of this Version
Environmental Studies Undergraduate Student Thesis, University of Nebraska–Lincoln, 2016
Western Tiger Salamander in eastern Nebraska have experienced population declines in recent years. In eastern Nebraska there is a high degree of agricultural production compared to other regions of the state. Pyraclostrobin fungicide, a substance that has been shown to cause numerous deleterious effects to amphibian species via direct contact, is applied to cornfields in large amounts. While a number of experiments have been conducted showing the effects of pyraclostrobin via dermal contact in amphibians, little is known about the effects of fungicide bioaccumulation. In this study, 24 salamanders were split into 4 groups with each group ingesting earthworms which had been exposed to differing concentrations of fungicide. Group 1 was fed uncontaminated worms as a control, groups 2, 3, and 4, were fed worms exposed to 2.3%, 4.6%, and 9.2% fungicide concentrations, respectively. Feeding occurred once per week over 4 weeks. Over the course of the study no mortalities occurred, no skin lesions were found, and the average length and mass gains over 4 weeks did not differ significantly between the control and experimental groups. At this time there is no evidence to suggest that fungicide bioaccumulation via earthworm prey causes any deleterious effects in Western Tiger Salamanders. The results of this experiment were largely inconclusive due to the lack of observable or measurable deleterious effects.