Abstracts

Q.2-20: A rake sampling method to estimate biomass of submersed aquatic vegetation for waterfowl in managed South Carolina coastal wetlands

C. Sharp, Department of Forestry and Environmental Conservation, Clemson University
J. Eidson, Department of Forestry and Environmental Conservation, Clemson University
C. Leland, Department of Forestry and Environmental Conservation, Clemson University
T. Turner, Department of Forestry and Environmental Conservation, Clemson University
S. Braswell, Department of Forestry and Environmental Conservation, Clemson University
C. Watson, Department of Forestry and Environmental Conservation, Clemson University
J. Tolson, Department of Forestry and Environmental Conservation, Clemson University
R. Coen, Department of Forestry and Environmental Conservation, Clemson University
N. Masto, Department of Biology, Tennessee Technological University
B. Bauer, Nemours Wildlife Foundation
R. M. Kaminski, Department of Forestry and Environmental Conservation, Clemson University & James C. Kennedy Waterfowl and Wetlands Conservation Center, Clemson University

Presented by Nick Masto - Email: nmasto@g.clemson.edu

Managers of impounded brackish wetlands in coastal South Carolina manipulate water depth, hydroperiod, and salinity to promote growth of widgeongrass (Ruppia maritima) and other submersed aquatic vegetation (SAV) as forage for waterfowl. Researchers need accurate and precise methods to estimate SAV biomass and foraging carrying capacity of these wetlands for wintering waterfowl. These data are critical for habitat conservation planning and management in South Carolina. Therefore, we evaluated two rake sampling methods for predicting total and species-specific SAV biomass within managed tidal impoundments (MTIs) at Bear Island Wildlife Management Area in the Ashepoo-Combahee-Edisto Rivers Basin, South Carolina. We collected SAV from MTIs using a modified rake within 0.086 m2 cylindrical sampler (CS), a non-modified rake within 0.2-m2 quadrat (QS), and by hand within each enclosure after raking to calculate total SAV biomass (i.e., rake + hand grab = total). We used linear mixed models to evaluate rake sampling methods in predicting total (QS and CS) and species-specific SAV biomass (QS). Both rake sampling methods explained 95% of the variation in total and species-specific biomasses. Therefore, we recommend use of our rake-enclosure SAV sampling methods and regression equations to estimate SAV biomass in South Carolina MTIs and elsewhere applicable.