A visualization and analysis of the Salmon Creek Watershed for resource managers and community outreach

Thesis (Master's)--University of Washington, 2018Intermittent streams are low-order creeks that experience seasonal reductions in flow; upon flow reduction, pools of water are separated by dry stream bed. These residual pools are important habitat during dry months for the aquatic organisms living the watershed. The Salmon Creek Watershed is located in central coastal California and creek flow becomes intermittent over the summer months; Endangered Species Act listed species Coho salmon (Oncorhynchus kisutch) and Steelhead trout (Oncorhynchus mykiss) spawn and rear in the watershed. This study contains to two reports that examined juvenile salmonid habitat over the course of a 5-year drought that occurred in this region. The first report- Assessing late-summer juvenile salmonid abundance- A report for the Gold Ridge Resource Conservation District- used Poisson regressions to determine which variables – dissolved oxygen, temperature, surface area, maximum depth, and three variations on cover- were most important for late-summer juvenile salmonid abundance. Surface area and depth were most important for both steelhead trout and coho salmon abundance, supporting previous research. Management efforts should focus on lower creek reaches to support habitat during low flow periods and habitat connection to upper reaches. The second report- A GIS story of Salmon Creek- visualized and assessed the Salmon Creek Watershed Council’s data archive. Surveying has been ongoing since 2013; and this report looked at years 2013,2015,2016, and 2017. From the data, three different map types: time-series maps, ecological observation maps and watershed wide views. I identified that three of the consistently surveyed creeks- Nolan, Fay and Tannery- showed reductions in dry lengths from 2015 to 2017. The ecological observation maps were designed as community outreach tools to garner community interest and support in protecting critical habitat for the salmonids. The Watershed Council’s continuous survey of the creeks provides valuable information for managemen