The infestation of the emerald ash borer has led to changes in forest canopy cover throughout southeastern Michigan, thereby altering forest habitat conditions in general. Amphibians are extremely sensitive to any habitat changes, including canopy cover, and rely on ephemeral ponds in forests for breeding. Canopy cover often determines amphibian species richness and abundance. Ash trees are often ubiquitous in these ephemeral pond areas and the extreme ash mortality may impact amphibian populations. We examined the indirect effects of the emerald ash borer infestation on amphibian populations in southeastern Michigan. Study sites were chosen based on a chronosequence of the emerald ash borer infestation to account for time and consisted of an ephemeral pond area with ash mortality and an ephemeral pond area with no ash mortality. Amphibian surveys were performed and individuals were weighed, measured, and sexed. Water analysis including pH, dissolved oxygen, and temperature were performed. Dipnetting was done to determine abundance and species of larval amphibians.
Results/Conclusions
No significant differences were found in amphibian richness or abundance when comparing open ephemeral ponds with ash mortality to closed ponds with no mortality. No significant differences were found in pH or dissolved oxygen content in open versus closed canopy ponds. There was a larger difference in amphibian abundance when a pond area with extreme ash mortality was compared to a closed canopy site. The lack of statistically significant results may be due to the patchy nature of ash trees throughout the forests of southeastern Michigan.
