The Scott River includes California's largest wild population of coho salmon (Onchorhynchus kisutch); a species listed as threatened under both state and federal Endangered Species Acts. The Center for Watershed Sciences is partnered with California Trout and Western Rivers Conservancy to improve conservation strategies within the Scott River and its coldwater tributaries while maintaining agricultural land-use activities for private property-owners in the region. Monitoring throughout this watershed is focused on determining whether current conditions meet desirable streamflow and water temperature criteria for the success of the species and whether ongoing conservation activities have any positive effect on these conditions.

The purpose of this study is to better understand the spawning migration and timing of rainbow trout in the spring-fed Fall River of Northern California.

The Little Shasta River project is the third phase of CWS’ research in the Shasta basin – moving past baseline assessment and demonstration projects to private landowner collaboration. The Center for Watershed Sciences is partnering with private landowners, California Trout, and The Nature Conservancy to identify how heritage rangeland can be managed to ensure the long-term viability of both rangeland and recover coho salmon populations. Our research shows how science can inform and influence the management of rangeland and environmental resources.

Through consultation with CDFW, California Trout (CalTrout) initiated a “pilot” restoration project within the Carbon Reach of the Hat Creek WTA in October 2015. The focus of this pilot project was the introduction of large woody debris (LWD) structures to help stabilize fine sediment, increase spatial variability in flow velocities and depths, and also provide overhead cover to wild trout. Using high-resolution velocity and topographic data collected prior to and following the installation of LWD structures in Hat Creek, the UC Davis Center for Watershed Sciences evaluated hydraulic and geomorphic changes to the Carbon Reach associated with restoration activities.

The Center for Watershed Sciences is investigating harvested rice fields as potential salmon nurseries that could help boost struggling Central Valley populations. Experimental releases of young hatchery salmon on the Yolo Bypass near Sacramento indicate that parts of the 57,000-acre floodway could make productive rearing habitat at relatively little cost to farmers.

The California Environmental Flows Framework (CEFF) provides an approach for determining ecological flow criteria and guidance for developing environmental flow recommendations that can accommodate a variety of stream types and biological communities, while supporting regulatory and management agency programs aimed at protecting beneficial uses for aquatic life. CEFF applies a Functional Flows approach and provides ecological flow criteria based on the natural variability of ecologically-relevant functional flow metrics. It provides a process for considering physical and biological constraints within a stream system and provides guidance on developing environmental flow recommendations that balance ecological and water management objectives.

Mountain meadow wetlands provide disproportionally important ecological services as compared to the area they cover in the Sierra Nevada by providing wetland-associated biodiversity, attenuating floods, and by contributing to downstream water quality and flow. However, degradation and loss of hydrologic function are widespread in Sierran meadows due to past and continuing anthropogenic effects including grazing management, diversions, roads and culverts, as well as non-native species.