Evaluating the influence white-tailed deer have on wetland vegetation types with respect to wetland birds at Shiawassee National Wildlife Refuge, Saginaw, MI.

摘要

White-tailed deer (Odocoileus virginianus), can be keystone herbivores in forest ecosystems and greatly impact forest conditions. Results of previous deer herbivory research could cause biologists concern when managing wetlands as suitable habitat for migratory waterfowl since high levels of herbivory can negatively impact plant communities. There is a knowledge gap on how deer use of wetland vegetation types may affect bird use of those same wetlands. Our objectives were to 1) evaluate white-tailed deer habitat suitability within a landscape dominated by wetlands, 2) quantify and compare use of wetland vegetation types by white-tailed deer to use by wetland bird communities, and 3) quantify white-tailed deer herbivory within various wetland types. We classified 1 x 1 m aerial imagery data in ArcGIS v10.0 and developed a white-tailed deer habitat suitability index (HSI) model. We conducted driving during crepuscular hours alternating morning and evening sampling times per week from May - August 2011 and 2012 in 3 wetland types. We constructed exclosures and paired them with open areas in moist soil, perennial marsh, lakeplain prairie, and bottomland hardwood forest vegetation types where we measured horizontal cover, vertical cover, species richness, total above ground biomass, and seed biomass. Wetlands provide highly suitable deer habitat, deer are using wetlands but not impacting wetland bird communities, and deer herbivory is not negatively impacting the composition and structure of wetland plant communities. These results are being used to help guide management decision making at Shiawassee National Wildlife Refuge.