Date of Award

2011

Degree Type

Open Access Thesis

Degree Name

Master of Science (MS)

Department

Biological Sciences

First Advisor

Stephen C. Richter

Department Affiliation

Biological Sciences

Abstract

Amphibians are in a worldwide decline. Among the many causes for amphibian declines, habitat loss and alteration remains one of the most significant. A lack of federal protection for isolated wetlands that provide habitat for unique species has resulted in the loss of breeding habitat and unregulated mitigation practices. Ponds built for mitigation purposes often do not replicate the lost ponds in structure or ecological processes. A lack of general monitoring has produced a void in knowledge of what long-term role constructed ponds play in shaping amphibian communities. My objective was to compare amphibian communities of natural ponds and multiple types of constructed ponds in the Daniel Boone National Forest, Kentucky. A suite of habitat variables including canopy cover, hydroperiod, upland coarse woody debris, aquatic vegetation, maximum depth, Ohio Wetland Rapid Assessment Score (ORAM), and pond type were recorded to examine relationships between amphibian species and habitat variables. Community comparisons were made using canonical correspondence analysis (CCA) and one-way analysis of similarity (ANOSIM). Stepwise regression models were developed to predict individual species abundance based on the habitat variables. Amphibian communities differed significantly between ponds types (natural, new construction method, old construction method). Additionally, wood frogs (Rana sylvatica) and marbled salamanders (Ambystoma opacum) were almost exclusively found in natural, ephemeral ponds, whereas large ranid frogs (R. clamitans, R. catesbeiana, R. palustris) were only found breeding in permanent, constructed ponds. Habitat predictors for some species showed differing preferences for hydroperiod, canopy cover, maximum depth, ORAM score, and amount of upland coarse woody debris. New construction methods were intermediate between old construction method and natural ponds in terms of habitat variables and amphibian community composition. As amphibian conservation and management become increasingly important in light of rapid declines, the ability to construct habitat and monitor it efficiently will be crucial in preservation of species. The results of this research underscore the need for monitoring of constructed wetlands in order to verify if goals are met and to assess ecological condition.

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