Seed Predation and Forest Regeneration in a Second Growth Forest
Advisor: Professor Lynn Christenson
For my senior thesis project, I have been examining the effects of small mammal predation on forest regeneration within the Vassar Farm and Ecological Preserve (VFEP). My study incorporated six study sites: three ten meter by ten meter fenced plots to exclude deer and three unfenced plots of the same size. The first phase of my project utilized small mammal trapping to determine the density and diversity of gramnivores (seed predators) within the sites. Five traps were placed haphazardly in each study site and set twice a week for four weeks. After completing this stage, I then looked at specific predation rates and predator preference of five seeds commonly available in the VFEP: American Elm, Black Cherry, White Ash, Northern Red Oak and Sugar Maple. In order to determine which predators preferred which seeds, I covered steel plates with a thin layer of mineral oil and powdered charcoal and placed them around the seeds (see attached picture). In case these plates somehow deterred animals from their usual predation habits, we ran this experiment again without the plates to serve as a control. For the thirds and final phase of this project, I built baskets to collect the seed rain within the plots in order to determine the availability of seeds within the site.
This semester I will work on the analysis of this data, which will include creating a model that simulates the cycle of seed availability, predation and overall regeneration. Using this data, my goal is to be able to accurately predict the fate of a single seed given its genus. This information will further help us to understand the impact of gramnivore predation on the VFEP and allow us to continue with effective conservation and restoration practices.