Final Report: Evaluating how beaver dams and beaver dam analogues maintain wildlife diversity and water sources for livestock during drought and climate change in the Great Basin
Dates
Publication Date
2018-04-06
Citation
2018-04-06, Final Report: Evaluating how beaver dams and beaver dam analogues maintain wildlife diversity and water sources for livestock during drought and climate change in the Great Basin: .
Summary
The increasing threat of drought to the productivity of US rangelands is a socioeconomic and ecological problem that needs pragmatic solutions. The urgency of this issue has fostered partnerships between private landowners and public natural resource managers to find solutions. The use of North American beaver (Castor canadensis) to increase surface water in arid landscapes is one pre-emptive measure that is gaining interest because of the remarkable ability of beavers to impound water. In places where beaver are no longer present, some landowners and managers are installing artificial structures made of rock and wood with the intention of mimicking effects of beaver dams. Although this ecosystem engineering is enticing, few scientific [...]
Summary
The increasing threat of drought to the productivity of US rangelands is a socioeconomic and ecological problem that needs pragmatic solutions. The urgency of this issue has fostered partnerships between private landowners and public natural resource managers to find solutions. The use of North American beaver (Castor canadensis) to increase surface water in arid landscapes is one pre-emptive measure that is gaining interest because of the remarkable ability of beavers to impound water. In places where beaver are no longer present, some landowners and managers are installing artificial structures made of rock and wood with the intention of mimicking effects of beaver dams. Although this ecosystem engineering is enticing, few scientific studies have been conducted to evaluate these practices. As an initial assessment, we conducted an inventory of all beaver-related restoration projects to date in rangeland streams across the western US. Preliminary results suggest that the relocation of nuisance beaver into unoccupied habitats is the most common practice of the nearly 100 projects surveyed. The primary goals of projects were increasing storage of surface water, followed by restoring riparian vegetation, reducing sedimentation, and improving habitat for fish and wildlife. Installation of artificial structures with names like “beaver dam analogues” and “artificial beaver dams” is less common, but increasing since 2005. Some projects installed hundreds of these structures. We found little effort to monitor project outcomes and an incomplete understanding of their ecological and hydro-geomorphic effects. Better monitoring of project outcomes would provide much-needed empirical data and, to meet this need, we developed a biodiversity assessment protocol using environmental DNA (eDNA) extracted from water samples. We sampled 11 streams across a range of project types. Preliminary results suggest this approach provides important biological information about species occupancy as well as possible relative information about stream condition and recovery trajectories.
