Assessing Urban Habitat Connectivity: Using Circuit Theory to Model Blanding\u27s Turtle Movement

Abstract

With the burgeoning growth of urbanization, urban landscapes have become more heterogeneous and less suitable for nonhuman organisms. This translates into isolated patches of suitable habitat interrupted by anthropogenic infrastructure. The loss of continuous habitats has created a myriad of negative ecological effects, including loss of genetic diversity, overexploitation of local resources, and local extinction. In response to these concerns, ecologists have begun modeling habitat connectivity in order to connect isolated habitat patches and facilitate animal movement throughout highly fragmented urban areas. Although this modeling is critical, there is no standard model used. One model, based on circuit theory, has shown promise over the last ten years. In this model, animals are treated as ‘current\u27 flowing through the ‘resistors\u27 of the landscape. We selected a highly fragmented area - the Twin Cities Metro Region - in order to test the applicability of circuit theory to our target species: the Blanding\u27s Turtle. We concluded that the model is highly effective at incorporating several different resistance layers based on existing landscape features while accurately predicting high- movement pathways. Our final output models contain important insight on dispersal patterns for the species, and have the potential to aid in future conservation efforts