Snowshoe hares (Lepus americanus) are a critically important prey species for Canada lynx (Lynx canadensis). Determination of snowshoe hare distribution and abundance is needed in western Wyoming for lynx conservation. We used linear regression to examine the correlations between snowshoe hare density, as determined by mark-recapture estimates, and fecal pellet plot counts on both uncleared and annually cleared plots on the Bridger-Teton National Forest, western Wyoming. We found significant correlations between hare density estimates and fecal pellet counts for both uncleared and annually cleared pellet counts; however the relationship was much stronger for annually cleared pellet counts. Adjusting the buffer size by omitting hard habitat edges (not used by hares) around the trapping grids improved correlations between hare density and fecal pellet counts further. We recommend pellet counts from annually cleared plots be used when precise estimates of snowshoe hare abundance are required. Though precision is sacrificed when using uncleared plots, they are useful as a coarse index of habitat use by hares. The derived regression equations should be used to identify foraging habitat for lynx in western Wyoming. In addition to snowshoe hares, in western Wyoming red squirrels (Tamiasciurus hudsonicus) and grouse (Bonasa umbellus and Dendragapus obscurus) are used by Canada lynx. Whether young forests or older multi-storied forests contain more snowshoe hares, red squirrels, and grouse in western Wyoming is currently unknown. We estimated snowshoe hare density, and indexed red squirrel and forest grouse abundance in 3 classes of 30-70-year-old lodgepole pine (Pinus contorta) and 4 classes of mature multi-storied forest with a spruce (Picea engelmannii)-fir (Abies lasiocarpa) component. We recorded landscape and forest structure characteristics to understand how these influence lynx prey abundance. Overall, snowshoe hares, red squirrels, and forest grouse were more abundant in multi-storied forests than young forests. Forest attributes that predicted prey abundance were often more prevalent in multi-storied forests. Results from this study suggest that multi-storied forests with a spruce-fir component were disproportionately important to snowshoe hares, red squirrels, and forest grouse in western Wyoming. Canada lynx conservation efforts should focus on maintaining, enhancing, and promoting multi-storied forests in this region.

Wildlife biologists and land managers tasked with the recovery of the endangered Lower Keys marsh rabbit (LKMR; Sylvilagus palustris hefneri) were in need of a current population estimate as well as a method to estimate the LKMR population annually. Habitat loss and fragmentation from population growth and development have threatened the existence of the LKMR. Establishing and understanding long-term habitat availability for the LKMR is important for determining causes of historical population declines as well as designing and implementing successful recovery plans. I conducted a range-wide pellet survey and a mark-recapture study to estimate the LKMR population. I evaluated the fit of 5 models and considered the variation in behavioral response model the best model. I correlated (r2 = 0.913) this model's rabbit abundance estimates to pellet density in 11 patches and generated a range-wide population estimate of 317, a western clade population of 257, an eastern clade population of 25, and translocated LKMR populations of 35 and 0 on Little Pine and Water keys, respectively. This prediction equation provides managers a quick, efficient, and non-invasive method to estimate LKMR abundance from pellet counts. To quantify the amount of habitat loss and fragmentation that occurred over the last 50 years, I systematically delineated and compared potential LKMR habitat using 1959 and 2006 aerial photographs. Additionally, I investigated if other factors could have reduced the amount of suitable habitat available for the LKMR with a comparison of habitat loss and fragmentation on a developed island and an undeveloped island. Range-wide, I found that number of habitat patches increased by 38, total class area decreased by 49.0%, and mean patch size decreased by 44.3%. Mean shape index increased by 4.2% and mean proximity index decreased by 13%. Both the 1959 and 2006 connectance indices were low while the 2006 set decreased 12.1%. I observed the same patterns of habitat loss and fragmentation on both the developed and undeveloped islands as I did in the range-wide landscape analysis. I found that LKMR habitat has declined in area and become more fragmented over the last 50 years. Habitat loss and fragmentation by development have directly endangered the LKMR; however, sea level rise and woody encroachment also could have historically caused habitat loss and fragmentation. Although development in LKMR habitat was halted, sea-level rise and woody encroachment could continue to alter LKMR habitat.