Sarah M. Yarnell

Sarah M. Yarnell is an Associate Professional Researcher at the Center for Watershed Sciences, University of California, Davis, and a part-time lecturer in the Department of Earth & Planetary Sciences. Her work integrates hydrology, ecology, and geomorphology to study river ecosystems, with a focus on environmental flows, montane meadow restoration, and amphibian conservation. She is a leading expert on the Foothill yellow-legged frog (Rana boylii) and has pioneered sediment transport modeling for evaluating instream habitats.

Education: Ph.D. in Hydrologic Sciences (UC Davis, 2005), M.S. in Geology (UC Davis, 2000), B.S. in Environmental Biology & Management (UC Davis, 1995).

Research interests include the impacts of hydrologic regimes on aquatic biota, functional flows for river ecosystems, and the ecological importance of snowmelt processes. She collaborates with government agencies and NGOs on projects such as the California Environmental Flows Framework, meadow restoration in Sierra Nevada and Cascade ranges, and beaver dam analogue techniques. Her teaching includes field-based courses like Ecogeomorphology.

Key projects span 20+ years, addressing topics like fish sensitivity to baseflows, functional flow criteria development, and post-fire meadow recovery. She advises students through the Hydrologic Sciences Graduate Group and engages in interdisciplinary teams to advance water management strategies.