Year of Award


Document Type

Professional Paper

Degree Type

Master of Interdisciplinary Studies (MIS)

Degree Name

Interdisciplinary Studies

Other Degree Name/Area of Focus

Wildlife Disease Ecology

Department or School/College

Interdisciplinary Studies Program

Committee Co-chair

Michael Minnick, Richard Douglass

Commitee Members

Jon Graham, Amy Kuenzi


University of Montana


The effects of deer mouse immigration into buildings in response to horse grazing were examined during this study. Treatment (grazing) and control (no grazing) pastures were created to simulate interactions between peridomestic (in or around buildings or structures in close proximity to humans) and sylvan settings. Each pasture was 0.6 ha in size and contained two small buildings. Twelve experimental trials were conducted from April through June 2005; October through November 2005; February 2006; June through August 2007; and May through July 2008. During these trials, mouse movements into buildings were monitored using a passive integrated transponder (PIT) tag transceiver and pit tags on individual mice in control and treatment (grazed) pastures for 9 days. A total of 76 individual mice entered the buildings, with 63 individual mice entering the buildings before grazing, 42 during grazing, and 32 after grazing. In the control pasture, 45 individuals entered buildings, with 39 mice entering the buildings in the period before, 24 during, and 18 after. In the treatment pasture, a total of 31 individual mice were recorded with 24 individuals entering before, 18 during, and 14 afterward. Results revealed no significant two or three way interaction between Timing, Food or Grazing. Regardless of treatment (grazing or food), the average number of mice entering the buildings was greatest before horses were introduced, fewer when horses were present, and the least after horses were removed. There was no significant difference between the number of female and male mice that entered the buildings. There was a significant difference between the number of female and male movements during and after grazing. More male movements into buildings occurred than female movements while horses were present, and more female entrances occurred than male entrances after horses were removed.



© Copyright 2009 Abigail Jean Leary