|Document Type:||Journal Article|
|Title:||Restoring salmon habitat for a changing climate|
|Author:||T. J. Beechie, H. Imaki, Jennifer Greene, Alisa Wade, Huan Wu, G. R. Pess, P. Roni, John Kimball, Jack Stanford, Peter M. Kiffney, Nathan Mantua|
|Journal:||River Research and Applications|
|Keywords:||restoration, climate change, salmon habitat, stream flow, stream temperature|
An important question for salmon restoration efforts in the western US is “How should habitat restoration plans be altered to accommodate climate change effects on stream flow and temperature?” We developed a decision support process for adapting salmon recovery plans that incorporates (1) local habitat factors limiting salmon recovery, (2) scenarios of climate change effects on stream flow and temperature, (3) the ability of restoration actions to ameliorate climate change effects, and (4) the ability of restoration actions to increase habitat diversity and salmon population resilience. To facilitate the use of this decision support framework, we mapped scenarios of future stream flow and temperature in the Pacific Northwest region, and reviewed literature on habitat restoration actions to determine whether they ameliorate a climate change effect or increase life history diversity and salmon resilience. Under the climate change scenarios considered here, summer low flows decrease by 35-75% west of the Cascade Mountains, maximum monthly flows increase by 10-60% across most of the region, and stream temperatures increase between 2-6°C by 2070-2099. Based on our literature review, we found that restoring floodplain connectivity, restoring stream flow regimes, and re-aggrading incised channels are most likely to ameliorate stream flow and temperature changes and increase habitat diversity and population resilience. By contrast, most restoration actions focused on in-stream rehabilitation are unlikely to ameliorate climate change effects. Finally, we illustrate how the decision support process can be used to evaluate whether climate change should alter the types or priority of restoration actions in a salmon habitat restoration plan.
This article includes maps of predicted climate change effects on stream flow and temperature in the PNW, assesses which kinds of restoration actions might ameliorate specific climate change effects, and provides a simple decision support framework for deciding whether restoration plans or actions should be altered to accommodate climate change.