What is BRAT?
The Beaver Restoration Assessment Tool (BRAT) is a decision support and planning tool intended to help researchers and resource managers assess the potential for beaver as a stream conservation and restoration agent over large regions and watersheds.
The BRAT model can be run with widely available existing data sets, and is used to identify opportunities, potential conflicts and constraints through a mix of an assessment of existing resources and a scenario-based assessment of potential futures. The backbone to BRAT are spatial models that predict the capacity of riverscapes to support dam-building activity by beaver. The beaver-dam building capacity model uses both existing and historic vegetation layers to show current capacity and historic capacity.
Capacity is estimated using the following five inputs:
The BRAT model can be run with widely available existing data sets, and is used to identify opportunities, potential conflicts and constraints through a mix of an assessment of existing resources and a scenario-based assessment of potential futures. The backbone to BRAT are spatial models that predict the capacity of riverscapes to support dam-building activity by beaver. The beaver-dam building capacity model uses both existing and historic vegetation layers to show current capacity and historic capacity.
Capacity is estimated using the following five inputs:
- a perennial water source
- availability of dam building materials
- ability to build a dam at baseflow
- likelihood of dams to withstand a typical flood
- likelihood that stream gradient would limit or completely eliminate dam building by beaver.
Where have we used BRAT?
significance of project
By combining capacity and decision support approaches, researchers and resource managers have the information necessary to determine where and at what level reintroduction of beaver and/or conservation is appropriate.
How the data can be used
BRAT has been applied in the following areas: Areas we have contracts in place to apply this tool:
- John Day
- Northern California
- State of Idaho
- Greater Yellowstone area
- Nevada
- Wyoming
- Parts of Utah
