Chinook salmon (Oncorhynchus tshawytscha) are a culturally, ecologically, and economically important species increasingly threatened by climate change. The cultural and economic well-being of the Lummi Nation are bound to the health of salmon stocks in the South Fork Nooksack River, where increasing stream temperatures are degrading salmon spawning and rearing habitat. For Chinook and other salmon to survive and reproduce in warming waters, cool-water refuge is critical. This research will assess the effectiveness of engineered log jams (ELJ) construction as a strategy for creating cool-water refuge by promoting the development of deep pools and localized upwellings of shallow subsurface (i.e., hyporheic) water.

The proposed research is a collaboration between the Lummi Indian Business Council Natural Resources Department (LNR) and Western Washington University researchers. The results of this research project will provide evidence-based recommendations that will guide the design of future ELJ projects undertaken by LNR and other management agencies in the South Fork Nooksack and in other warming waters. These recommendations will be directly applicable to the development of effective climate adaptation strategies for threatened Chinook and other salmon populations, as well as the Southern Resident Killer Whales (Orcinus Orca) that depend on them as a food source.