Date of Award
Zoo and Conservation Science-BS
Biology & Earth Science
Dr. Sarah Bouchard
First Committee Member
Dr. Sarah Bouchard
Second Committee Member
Dr. Michael Hoggarth
Third Committee Member
Dr. Robin Grote
Leaf Litter, Gray Tree Frog, Predation
Biology | Zoology
Plant litter is an important resource for consumers, particularly in freshwater environments where it influences the development processes of larval amphibians. Leaf litter alters the physiochemical environment by lowering dissolved oxygen while increasing nitrogen, tannin, and phenolic acid levels. Many anuran species show plastic responses to the threat of predation. This is communicated through a kairomone when a tadpole is consumed, allowing surviving tadpoles to alter their behavior and morphology to evade predators. The purpose of this study was to analyze the interactive effects of leaf litter and predation on gray treefrog tadpoles (Hyla versicolor). The chemical output of the leaf litter was manipulated by soaking a subset of each litter type to remove leachates. Larvae were reared in outdoor mesocosms with one of the following leaf litter types: un-soaked red maple, soaked red maple, un-soaked pin oak, soaked pin oak, or no leaf litter. Half of the tanks contained caged dragonfly larvae (Plathemis lydia) predators. We measured elements of water quality, tadpole growth, tail morphology, froglet size, and time to metamorphose. Maple leaf litter reduced water clarity and introduced more nitrogen than oak leaves. Predation decreased growth rate in maple tanks, and increased growth rate in oak tanks. Both maple and oak elicited bigger tails under predation, however larvae in oak leaf litter showed the greatest shift in tail morphology by developing deeper tails under predation. These results suggest the physiochemical properties of maple and oak leaf litter elicit different responses from predation threats. This study has important implications of the physiochemical relationship between leaf litter and predation cues, and the combined effect on the growth and development of Hyla versicolor tadpoles.
McCauley, Dani, "The Effects of Leaf Litter On Predation Cue Response in Gray Tree Frog Tadpoles, Hyla Versicolor" (2020). Distinction Papers. 83.
Available for download on Thursday, May 20, 2021