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Hancock Springs A natural lab for studying the roles of physical habitat, nutrient availability, and non-native species to inform river restoration . John Jorgensen Yakama Nation Fisheries.
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Hancock Springs A natural lab for studying the roles of physical habitat, nutrient availability, and non-native species to inform river restoration John Jorgensen Yakama Nation Fisheries
Today’s talk will cover:- The regional problem: Reduced natural production- Factors limiting natural production- An integrated restoration approach- Discussion of Hancock Springs- Summary and Conclusions- Q&A/Discussion
Salmon population declines are often due to cumulative effects of many factors
Biomass Reductions Gresch et al. 2000
Factors limiting natural production“The Big 3”:1. Habitat lossand degradation2. Loss of marine derived nutrients (MDN)3. Deleterious presence of non-native fishes
Upper Columbia Natural Production Restoration Program Goal: To identify, test, evaluate, and implement measures to increase natural production of anadromous salmonids in the Upper Columbia River Basin.
Upper Columbia Natural Production Restoration Program Current Projects: Upper Columbia Nutrient Enhancement Project (Twisp River) Hancock Springs Project (Today’s talk)
Goal: Use Hancock Springs to quantify separate and combined effects of habitat restoration, nutrient addition, and non-native fish removal on natural production of anadromous salmonids. Hancock Springs Project
Obj. 1: Evaluate fine scale responses to a series of restorative treatments Hancock Springs Project
Obj. 2: Understand the contributions of spring creeks in Upper Columbia tributaries Hancock Springs Project
Obj. 3 Use results to guide larger restoration actions Hancock Springs Project
Natural Production in HS Natural Production
Changes Before After
2012 SpawningSteelhead Redds (treatment 7) (control 0)Chinook Redds (treatment 12) (control 1)
Reach 1(treatment ) Reach 2 (Control) DEMCHaMP Digital Elevation Model
Benefits/Opportunities HS provides a thermally and hydrologically stable stream-scale system for evaluating restoration treatments that address the “Big 3” limiting factors, not feasible at larger river scales: Physical habitat restoration Nutrient addition Removal of non-natives (brook trout)
Benefits/Opportunities HS provides the opportunity to quantify effects of various restoration treatments within and between treatment and control reaches in ways not feasible at larger river scales. HS serves as a communal stream scale research facility to help researchers collect data to asses ecological functions associated with restoration measures and to validate ecological models.
Project history/Treatment structure 2005: Habitat in HS was determined to be prohibiting natural production; restoration potential identified 2006-2011: Initial and engineered habitat restoration in Reach 1 completed in 2011.
Treatment structure • 2012-2014: • Physical and biological monitoring in Reach 1 (treatment) and Reach 2 (control) implemented to evaluate responses to habitat restoration. • 1. Do nutrient concentrations appear to substantially limit • natural production? • 2. Does the presence of brook trout substantially restrict natural production?
Treatment structure Subsequent restoration treatments depend on outcomes of 2012 - 2014 nutrient and brook trout assessments Consistent physical habitat and biological monitoring occurs annually in both reaches
Summary and Conclusions Mitigating multiple ecological limitations in altered habitats often requires an integrated approach of multiple treatments Hancock Springs provides a unique and valuable opportunity to study the separate and combined effects of habitat restoration, nutrient addition, and removal of non-natives. Initial results have been encouraging We look forward to collaborating with others to collectively contribute to the science of river restoration and increased natural production.