The Beaver Restoration Assessment Tool (BRAT) is planning tool intended to help researchers, restoration practitioners and resource managers assess the potential for beaver as a stream conservation and restoration agent over large regions and watersheds. At the heart of BRAT is a capacity model, which estimates the upper limit of dam density (dams per kilometer) for individual stream reaches throughout a drainage network. We focus on predicting where beavers could build dams and to what extent (as opposed to the more general case of where beaver could make a living), because it is the dam building activity they do as ecosystem engineers, which we are typically most interested in.

The BRAT model can be run with freely available national data sets, or with higher resolution data, and is used to identify opportunities, potential risks and constraints through a mix of assessment of existing resources and proximity to infrastructure. BRAT's backbone consists of spatial models that predict the capacity of riverscapes to support dam-building activity by beaver. By combining capacity and potential risk, researchers and resource managers have the information necessary to determine where and at what level reintroduction of beaver and/or conservation is appropriate.

• Getting Started with BRAT
• Report Issues, Ask Questions, and Get Help

Vision

BRAT is a tool for imaging what is possible. At the heart of this is a capacity model that models the capacity of riverscapes to support dam-building activity by beaver. As Ben Goldfarb, in this book Eager, The Surprising, Secret Life of Beavers and Why They Matter elegantly states, “Although BRAT’s primary value is technical, it is, too, an achievement of the imagination, a method for visualizing the magnificently ponded world that predated European trapping — a time machine to the Castorocene”.

The BRAT capacity model outputs ‘paint’ a vision of what watersheds once were, and what they could be if beaver were allowed to return. BRAT provides a vision for what is possible and how partnering with beaver can help increase the resilience of watersheds to drought, fire, and climate change.

What transforms BRAT from a capacity model to an assessment tool is its ability to model: 1) potential risk areas, 2) unsuitable or limited dam building opportunities, and 3) conservation and restoration opportunities. As such, the BRAT model identifies where streams are relative to human infrastructure and high intensity land use, and conservatively shows how that aligns with where beaver could build dams.

The BRAT model helps build realistic expectations about what beaver dam-building may achieve locally on a given stream, and also helps scale-up those expectations at the watershed level. BRAT model outputs can be used to initialize restoration and conservation planning and can also support initial conceptual design and siting of specific restoration actions. BRAT model outputs can also aid with expectation management, and conservation and restoration prioritization.

BRAT As A Restoration Planning Tool

BRAT and its sister R-CAT, can be used to plan and prioritize restoration projects as explained in the video below:

Implementing the Vision

We are actively pursuing funding opportunities to enable us to develop the above tools and disseminate them widely. If you or your organization would benefit from these tools, please feel free to contact us to discuss collaborative opportunities.