Meeting Abstract

120.1  Saturday, Jan. 7  Development of Climbing Performance and Behavior during Red-eyed Treefrog Metamorphosis– the Effects of Larval Competition LANDBERG, T*; WILLINK, B; NOSS, CF; GREENE, RS; VONESH, JR; WARKENTIN, KM; Murray State University, KY; University of Costa Rica; University of Florida; University of Victoria; Virginia Commonwealth University; Boston University

Anuran metamorphosis involves dramatic, rapid changes in morphology, locomotor performance, and behavior and is a critical period for dispersal from larval habitats. For arboreal species, climbing is the most important locomotor mode for dispersal and foraging. While swimming, jumping, and even parachuting, gliding and adhesion have been studied extensively, climbing behaviors have not. We studied the development of climbing performance and behavior through metamorphosis for red-eyed treefrogs (Agalychnis callidryas) reared at three larval densities. Higher densities yielded smaller metamorphs. Metamorphosis takes ~6 d, with most tail resorption occurring in the 24 h after forelimb emergence. We observed two climbing gaits with distinct footfall patterns – a slow lateral sequence walk and a faster trot. Latency to climb decreased through metamorphosis. Generally, tail length had a negative effect on climbing performance. Climbing speed increased more through metamorphosis for smaller animals from higher densities than for larger animals from low density. Climbing speeds were similar by the end of metamorphosis, so carryover effects of larval competition decreased through metamorphosis. Proximate locomotor costs of emergence from the water early in metamorphosis are greatest with strong larval competition. Nonetheless, the ultimate fitness costs may be reduced by early stage (long-tailed) metamorphs having a reduced propensity to climb and thus potentially relying more on immobility as a defense.