Short-term response of deer mice (Peromyscus maniculatus) and white-footed mice (Peromyscus leucopus) to invasive shrub control

Invasive plants are becoming an ever-increasing challenge in the Midwest due to the threat they pose to native species and the environment. Thus understanding the impacts of these plants on native plants and animals is important to properly manage land. Autumn olive is an exotic invasive shrub that has invaded both the ground and shrub layer in prairie and young forest habitats. It has the ability to spread quickly and reduce the quality of native habitat, therefore is often subjected to invasive control methods. Deer mice (Peromyscus maniculatus) and white-footed mice (P. leucopus) are two species residing in habitat impacted by autumn olive. This study examined the short-term effects of removal of autumn olive on deer mice and white-footed mice in three protected nature preserves in northeast Indiana. Objectives of this study were to determine how invasive shrub control impacts the habitat, and how the two mice species respond to the change in habitat caused by invasive shrub control. Removal of the autumn olive from treatment sites during summer of 2013 was carried out using two invasive control techniques: mowing, and manual stump cut followed by herbicide application. Shrub and ground layer percent cover were used to determine differences in plant composition of each site. Two-way ANOVA analyses and nonmetric multidimensional scaling (NMDS) were used to quantify interactions between plants, plant composition, and Peromyscus distribution throughout all sites and trapping periods. To monitor Peromyscus populations, I trapped mice for 10 days during June 2013 (prior to autumn olive removal), and again for 10 days during July 2013, May 2014, and July 2014 (post-removal). I calculated abundances of deer and white-footed mice using capture-mark-recapture (CMR) methods and the Jolly-Seber POPAN model in program MARK. I found that that presence of autumn olive may be a predictor in the abundance of white-footed mice, and suggest that a higher intensity manipulation due to management efforts may lead to larger short-term increases in the abundance of both deer and white-footed mice. Studying mice population changes due to invasive control provides a broader insight on how land management techniques impact all native wildlife populations along with native plant populations