Meeting Abstract

P3.2  Thursday, Jan. 6  Short- and long-term effects of predation threat on development, growth, and behavior in wood frogs STARKEY, Dakota*; WARNE, Robin W.; CRESPI, Erica J.; Vassar College; Vassar College; Vassar College dastarkey@vassar.edu

In order to investigate the physiological and behavioral effects of predation threat during larval development in amphibians, we conducted a suite of experiments in which wood frog tadpoles were exposed to chemical cues of insect predation on conspecifics. In an outdoor mesocosm experiment tadpoles were exposed to predation cues of Corydalid insect larvae feeding on conspecifics in pulsed, chronic and control (no cue) exposures starting at Gosner stage 32-34 and continued through metamorphosis. In an associated behavioral-neuroendocrine experiment we found that tadpoles moved away from regions where predators were housed, thus validating that tadpoles detect and respond to the cue. To examine the neuroendocrine regulation of these behavioral responses tadpoles were also collected over a 48 hour period during this study for corticosterone assays. Tadpoles exposed to predator cues metamorphosed slightly later than control tadpoles, but there were no differences between pulsed or chronic predator exposures. There were also no differences in body length, condition, or weight at metamorphosis among these groups. Furthermore, no long-term differences in post-metamorphic locomotor or food intake behaviors were detecable. However, body weight was significantly and positively correlated with the number of strikes at prey and number of flies eaten, and negatively correlated to latency to first strike at prey. Taken together, the results of these experiments suggest that the predator cue as administered in these experiments caused a quick behavioral reaction and a modest lengthening of development time, but they did not manifest in long-term effects on body size and behavior. However, environmental stressors that affect the size at metamorphosis may have long-term effects on energy balance physiology and food intake behaviors that can affect overall fitness.