SREL Reprint #3776

Efficacy and costs of restoring wetland breeding habitat for imperiled amphibians in the Southeastern U.S.

E. Tucker Stonecypher1,2, Linda S. Lee2, Scott M. Weir3, Elizabeth G. King1, Charles E. Davis4,
and Stacey L. Lance2

1Odum School of Ecology, University of Georgia, Athens, GA, USA
2Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, USA
3Dawson Solutions LLC, Helena, MT, USA
4United States Department of Agriculture, Forest Service, Savannah River, Aiken, SC, USA

Abstract: Herbaceous isolated wetlands in the North American Southeastern Coastal Plain are important breeding sites for many imperiled amphibians. However, most are degraded from alterations to historic fire disturbance and hydrologic regimes. Without fire, encroaching woody vegetation can transition wetlands to more terrestrial conditions and negatively impact amphibian breeding habitat, yet few studies have experimentally tested the efficacy, cost, or temporal requirement of current methods to restore herbaceous wetland vegetation. Here, we tested the interaction of manipulating wetland canopy and leaf litter/duff to promote herbaceous vegetation within one year (i.e., one breeding season) in degraded herbaceous wetlands in South Carolina. We assessed plant response via herbaceous cover, composition, and species similarity to the wetland seed bank and then related treatment performance to treatment cost. Removing trees combined with burning, disturbing, or removing duff significantly increased herbaceous cover and proportions of wetland plants and graminoids. Removing trees alone did not improve herbaceous cover compared to closed-canopy controls, and manipulating duff alone had limited positive effects on plant cover and composition. The most expensive yet effective treatment was Tree Removal-Duff Removal, while Tree Removal-Duff Disturbance was the most cost-effective. At a minimum, we recommend removing trees and burning to kickstart herbaceous recovery. Promisingly, comparisons of our data with previous seed bank studies from these same wetlands indicate there was limited seed bank attrition during 30 years of woody encroachment. Results from this study should aid practitioners in choosing wetland restoration techniques to better conserve at-risk species in the Southeastern Coastal Plain.

Keywords: Cost-benefit; Duff; Isolated wetland; Herbaceous; Fire ecology; Rana capito

SREL Reprint #3776

Stonecypher, E. T., L. S. Lee, S. M. Weir, E. G. King, C. E. Davis, and S. L. Lance. 2024. Efficacy and costs of restoring wetland breeding habitat for imperiled amphibians in the Southeastern U.S. Wetlands 44(65).

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).