Comparing the Habitat Connectivity of Fisher and Marten in the Rocky Mountains, Usa

Overview

The connectivity of a species is the ability of its individuals to move, and importantly, to move between populations. We compare the connectivity of American marten (Martes americana), as well as fisher (Pekania pennanti) in western Montana and northern Idaho, to locate potential wildlife corridors that best serve the connectivity of both species. A niche model for fisher was available in the literature. To evaluate joint connectivity, we first constructed a niche-model for American marten using marten location data coupled with environmental covariates (topography, precipitation, snow, temperature, vegetation). Based on the assumption that identified areas of use also serve to facilitate connectivity, both niche models were transformed into resistance surfaces and connectivity nodes were placed randomly in highest ranked areas based on each species’ niche models. We then used Circuitscape to infer connectivity paths for each species. To compare these connectivity maps they were limited to mutually connected lands, and added together to create a single map of mutual connectivity. This was repeated at three thresholds of mutual connectivity. Continuation of this research will reveal the existence of potential wildlife corridors, and show if mutual connectivity in general exists for these species. This study may advise the management of these species, and it may open the possibility for further research into the mutual connectivity of other species.