Meeting Abstract

5.2  Friday, Jan. 4  Taking the good with the bad: Varying effects Roundup® on amphibian health. HANLON, S/M*; PARRIS, M/J; University of Memphis; University of Memphis hanloc2107@gmail.com

Organisms are exposed to a variety of perturbations in natural communities. In aquatic systems, pesticides are a common anthropogenic pressure that can negatively affect non-target organisms such as amphibians and alter larval anuran behavior, morphology, or life histories. Glyphosate, especially the commercial formulation Roundup®, is the most widely applied herbicide worldwide and is known to reduce amphibian performance and survival; however, the mechanism of such reductions is currently unknown. We conducted three separate studies on two anuran species to test how: 1) Roundup affects tadpole foraging behavior, 2) application timing alters the effect of Roundup on life history traits, and 3) Roundup affects tadpole mouthpart damage (a potential mechanism for reductions in life history traits). In experiment 1, Roundup significantly altered tadpole foraging behavior. In experiment 2, tadpoles exposed to Roundup later in development experienced increased growth and accelerated development compared to subjects in non-Roundup treatments. In experiment 3, tadpoles exposed to Roundup experienced significantly increased tadpole mouthpart damage (specifically to jaw sheath structures) in a dose-dependent manner. Additionally Roundup at higher concentrations significantly slowed development. Our results suggest that factors such as concentration and application timing may play an important role in understanding how anthropogenic disturbances (e.g. pesticides) affect non-target organisms.