Resistance-Surface-Based Wildlife Conservation Connectivity Modeling: Summary of Efforts in the United States and Guide for Practitioners

Resistance-surface-based connectivity modeling has become a widespread tool for conservation planning. The current ease with which connectivity models can be created, however, masks the numerous untested assumptions underlying both the rules that produce the resistance surface and the algorithms used to locate low-cost paths across the target landscape. Here we present a process to guide map creation, from conceptualization through validation, that seeks to better consider the complex biological issues inherent to connectivity modeling. Following this organized approach to connectivity modeling will help analysts prevent a plethora of issues common in recently created models, such as the failure to specify the temporal domain, purpose of the mapped connectivity, or the biological rationales for assigned pixel-level resistances. Following these steps will improve both the understanding and biological relevance of constructed connectivity maps.