Katie Seymore

M.S. Candidate, Shippensburg University

Conference Travel Grant Type 2 (Joint Aquatic Sciences Meeting)

Community Interactions between Leaf Litter, Caddisflies, and Amphibians in Vernal Pond Mesocosms

“Red maple trees are invading normally oak dominated eastern deciduous forests. This change in dominate species will alter the leaf litter dynamics in forested wetlands, including vernal ponds, changing nutrient contents available in those habitats. It is unknown how the shift from tough, slowly conditioned oak leaves to more supple, faster conditioned maple leaves will influence how organisms breakdown and release the nutrients available in vernal ponds. Furthermore, it is unknown how these changes will influence aquatic food webs. Previous studies addressed this relationship between leaf type and amphibian growth, however, they did not include caddisflies, a major detritivore in vernal ponds that is incremental in making nutrients available to other trophic levels. We conducted a mesocosm experiment investigating how the shift in leaf litter affected the growth and metamorphosis of amphibians when processed by caddisflies. Preliminary results suggest that the shift in leaf substrate is felt further up the foodweb. Maple leaves processed by caddisflies yield larger woodfrogs and had higher rates of survival to metamorphosis than oak with caddisflies and either leaf type in the absence of the detritivore. These results highlight our changing forest could impact wetland communities through their important allochthonous material. Additionally, we caution community biologist in overly simplifying experiments, causing erroneous results.”