The goal of my thesis was to identify the climatic and vegetation factors that influence snowshoe hare occupancy in Michigan. My objectives were to: 1) quantify snowshoe hare occupancy as related to climate change and 2) quantify the relationships between patch-level snowshoe hare occupancy and land cover change over time, current land cover, habitat structure, and mesocarnivore presence. In Chapter 1, I determined the most efficient transect configurations for winter track surveys and found that transects 150m in length with 100 or 75m spacing, or 125m in length with 75m spacing provided reliable estimates of hare occupancy. In Chapter 2, I researched climatic variables that are potentially linked to snowshoe hare population performance and assessed whether those factors affected the localized extinction of snowshoe hares . I found that localized extinction was mostly influenced by maximum temperature from May 15 - January 19; as temperature increased the likelihood of localized extinction increased. I also found that the total number of days with measurable snow on the ground affected localized extinction; as number of days with snow on the ground decreased the likelihood of localized extinction increased. In Chapter 3, I evaluated whether land cover change over time, current land cover, and habitat factors affected snowshoe hare occupancy and habitat use. I found that land cover change over time did not affect hare occupancy. Rather, a current land cover covariate (the ratio between forest and open edge) and the habitat covariates of visual obstruction at 1.0-1.5m above snow level and total stem density were important; all 3 parameters were positive but only the transect-level covariates were significant.
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