Brody Heraghty

Effect of Deer Exclosures on the Height and Abundance of Invasion Vegetation

Abstract

Invasive species are known to impact ecosystems negatively. They result in increased competition for resources and loss of available habitat for native species (Rai, P. K., & Singh, J. S. 2020). Invasive plants have no natural predators and can quickly overpopulate an area. White-tailed deer are a prevalent native herbivore in Vlei Marsh, Rhinebeck, NY, where we investigated the impact of deer herbivory on native and invasive plant species. Deer herbivory negatively alters soil composition, organic material availability for vegetation, and overall stunting plant growth (Stephan, J. G. et al. 2017). Indicator plant species are used to measure the impact of herbivory on ecosystems (Abella, S. R., Schetter, T. A., & Gallaher, T. D, 2017). Areas within the marsh were prepared with exclosures and control plots and used to determine the effects of deer herbivory on plant growth weekly over a five-week period. The three tallest heights of native (Betula pendula, Solidago) and invasive vegetation (Berberis thunbergii) were measured weekly over a five-week period. The weekly average heights of species graphed for each week of data collection and F-Tests were then calculated. Firstly, we found that native species had significantly (p < 0.05) higher growth over time when protected in a deer exclosure rather than being exposed to deer. The invasive species did not significantly (p > 0.05) differ between exclosed or exposed. This indicates that invasive plant species are not integrated into the diets of native white-tailed deer which allows these plants to dominate ecosystems.