Meeting Abstract

P2-34    Amphibians as Biomonitors in Rice Agroecosystems Born, AS*; Grajal-Puche , A; Propper , CR; Northern Arizona University asb382@nau.edu

Biodiversity is declining globally as a result of multiple external pressures including environmental pathogens, pollution, and habitat loss. Wetland habitats are ecosystems with high species endemism and biodiversity. Much of the worlds natural wetland ecosystems have been converted for agricultural purposes including rice cultivation. Rice field ecosystems now represent most the earth’s remaining wetlands. The growth of agricultural intensification has brought new stressors to these ecosystems including pesticide usage. One way to determine the overall health of these ecosystems is through monitoring amphibians inhabiting the rice fields. We hypothesized that amphibian health would differ between organic and conventional rice farming practices. To test this hypothesis, we compared several morphological measures indicative of developmental disruption in the Sierran treefrog (Pseudacris sierra) across fields utilizing both rice farming techniques. Adult frogs were captured along nightly transects and evaluated for weight, snout-vent length (SVL), and hind-limb measures of fluctuating asymmetry (FA), to determine if there were differences between animals inhabiting fields with differences in pesticide usage. Except for larger body size in one of the organic fields, we observed no difference in any values between conventional and organic farming practices, suggesting that either adult frogs move readily between field types, making determinations of developmental patterns of disruption difficult to determine, or these measures are not sensitive enough to detect differences that may exist across habitat types. In the future, evaluating FA and other morphological outcomes in tadpoles directly growing in each field type may help determine whether either agricultural practice leads to environmental stress during development.