Modeling the Capacity of Riverscapes to Support Dam-Building Beaver: Utah Statewide Implementation

Beaver dam-building activities lead to a cascade of hydrologic, geomorphic, and ecologic feedbacks that increase stream and riparian complexity and benefit aquatic and terrestrial biota. As a result, beaver are increasingly being used as a key component of stream and riparian restoration strategies. However, predictive spatial models resolving where within a drainage network beaver dams can be built and sustained are lacking. Moreover, a capacity model approach alone is not enough because many places that beaver might build a dam are in direct conflict with humans (e.g., damming of culverts or irrigation canals and flooding of roads). The Beaver Restoration Assessment Tool (BRAT) was developed to fill this void and serves as a decision support and planning tool intended to help resource managers, restoration practitioners, wildlife biologists and researchers assess the potential for beaver as a stream conservation and restoration agent over large regions. In 2012- 2013 we developed the beaver dam building capacity model portion of the tool and tested it in a pilot project in the Escalante and Logan watersheds. Results from the pilot study indicated that the model was effective at predicting beaver dam capacity across diverse physiographic settings. The project described herein improves upon and extends the pilot project to include Utah statewide coverage. The current project also develops and tests the decision support and planning components of the tool thus accounting for where beaver may pose potential nuisance problems, where ‘Living with Beaver’ strategies may be needed, where re-colonization and/ or reintroduction is most appropriate and identifies potential conservation and restoration areas for beaver. By combining the capacity and decision support approaches, resource managers have the necessary planning information to estimate where and at what level re-introduction of beaver and/or conservation is appropriate