Date of Graduation

2003

Document Type

Thesis

Degree Type

MS

Committee Chair

James T. Anderson

Abstract

The goal of this study was to evaluate the relative success of mitigation wetlands in West Virginia in supporting vegetation, invertebrate, and wildlife communities. Eleven mitigation wetlands were compared to 4 naturally occurring reference wetlands. For all vegetation species sampled, species richness (no. species/quadrat; P = 0.035), evenness (P = 0.033), and diversity (P = 0.025) were higher in mitigation than reference wetlands. Mean weighted averages per quadrat were similar between mitigation and reference wetlands (P = 0.242). Differences in vegetation composition between wetland types were reflected through ordination using Detrended Correspondence Analysis (DCA). Both mitigation and natural wetlands met criteria for hydrophytic vegetation according to the 1987 U.S. Army Corp of Engineers Wetland Delineation Manual. Overall invertebrate familial richness, diversity, density, and biomass were similar between mitigation and reference wetlands (P > 0.05). Within open water habitats, benthic density was higher in reference wetlands, but nektonic biomass was higher in mitigation wetlands (P < 0.05). Mitigation wetlands generally contained more abundant individual taxa than reference wetlands. Bird species richness (P = 0.711), diversity (P = 0.314), and abundance (P = 0.856) were similar between mitigation and reference wetlands. Waterbird (P = 0.013) and waterfowl (P = 0.013) abundance were higher in mitigation than reference wetlands. Frog species richness (P = 0.023), Wisconsin index value (P < 0.001), and abundance (P < 0.001) were higher in mitigation than reference wetlands. American bullfrog (Rana catesbeiana; WI: P = 0.033; A: P = 0.038), green frog (R. clamitans; WI: P = 0.012; A: P = 0.018), and pickerel frog (R. palustris; WI: P = 0.003; A: P = 0.005) were higher in mitigation wetlands. Habitat Suitability Index (HSI) scores for all 8 species combined were similar (P = 0.489) between wetland types. Red-winged blackbird (Agelaius phoeniceus; P = 0.001) and beaver (Castor canadensis; P = 0.037) HSI values were higher in natural than mitigation wetlands. All other speciesí SI values were similar between wetland types. Differences in vegetation and invertebrate community composition and structure likely contribute to differences in wildlife communities between wetland types, although Canonical Correspondence Analysis revealed no correlation between environmental variables and wildlife abundance. These data indicate that mitigation wetlands in West Virginia currently meet and exceed reference standards, although more time is needed for wetland stabilization. Numerous management strategies should be incorporated to facilitate colonization and proliferation of diverse wildlife taxa among current or future mitigation wetland.

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