Mapping Regional Wildlife Habitat Connectivity

We developed a wildlife habitat connectivity map for the Oregon portion of the Regional Conservation Strategy boundary. To make this map we solicited species experts for the Northern red-legged frog (Rana aurora), American beaver (Castor canadensis), and Douglas squirrel (Tamiasciurus douglasii) in order to determine the salient habitat requirements for each species. We then created GIS models of each specie’s probable distribution over the study area. The models are composed of landcover, maximum size of a canopy gap the animal will cross, maximum distance from water, aversion to development and much other data. The intention was to create a model that shows the spatial distribution of habitat as well as areas that are not habitat but through which the animal will travel and areas that are a barrier to the animal’s movement. We used these models to create raster layers that depicted the permeability of the landscape to animal movement and then modeled movement pathways in Circuitscape, a program that uses circuit theory to determine how well a set of points are connected based on a resistance surface. We used all of the Metro managed properties as the anchors for the connectivity modeling. We ran the model for all three surrogate species and then combined the models into a map of regional wildlife habitat connectivity. This effort will be repeated in the next several years for an additional 30-40 species as part of a larger effort by OCAMP to map statewide wildlife habitat connectivity.