Landscape Restoration Gaps

Landscape Restoration Gaps
Janine Castro (Portland State University)
Reaching Beyond the Reach: Using a Stepping-stone Approach to Restore Connectivity
Decades of time and energy have been spent on river restoration throughout North America. Aquatic restoration projects started small - small in scope, scale, and budget -- but over the last several decades have become dramatically larger and more complex, and hence more expensive. Individual projects have coalesced into programs, and programs have become careers. Yet, the perennial question remains -- what have we achieved? While many of our questions will remain unanswered, there is mounting evidence that larger, more complex projects expand and enhance aquatic habitat. Now, instead of working at the site-scale, projects are frequently implemented at the reach or multi-reach scale. But where do we go from here? How do we reach beyond the reach?
Since 2010, restoration projects in the lower Columbia River have been evaluated by an Expert Regional Technical Group that considers the potential benefits to juvenile salmon. Original criteria favored larger restoration projects but provided little guidance for the spatial distribution of projects along the river. Recognizing this limitation, in 2019 the ERTG developed a landscape framework for restoration to assess and reduce habitat discontinuities. Restoration actions are now evaluated using a landscape ecology approach and a stepping-stone model. Relative distance between restored habitat patches (or gaps) are now evaluated on an equal basis with project size. This approach operationalizes landscape ecology-based decisions for migratory salmon and restores linkages between river reaches. Initial monitoring in the Estuary shows that tighter linkages connecting high quality habitat patches produce synergistic benefits for juvenile salmon.
But how does this relate to beaver? Beaver migrate throughout aquatic systems, but can also migrate through terrestrial systems. If a project goal is beaver recolonization, then we need to ensure that gap sizes between habitat patches are scaled according to beaver life history needs and migration patterns.
Janine Castro is the Project Leader for the US Fish and Wildlife Service Fisheries Office in Vancouver, Washington. She has worked as a Geomorphologist for the Fish and Wildlife Service for 23 years and spent the preceding 10 years working for the Natural Resources Conservation Service. Janine provides national and international training on stream restoration, river science, geomorphology, and public speaking for scientists. Janine is one of the five founding members of River Restoration Northwest, the co-founder of Science Talk, is a co-founder and Technical Director of Portland State University’s River Restoration Professional Certificate Program, and is a member of the Columbia Estuary Ecosystem Restoration Program’s Expert Regional Technical Group, which reviews ecosystem restoration actions in the floodplain of the lower Columbia River and estuary. Janine was a co-author and editor of the first few versions of the interagency Beaver Restoration Guidebook.