Examining the relationship between Longfin Smelt, zooplankton, and flow in the San Francisco Bay Delta

Project Number
Project Date Range
Funding Agency
Delta Stewardship Council, Delta Science Program
Focus Area(s)
Education, Training and Public Information

The number of longfin smelt in the San Francisco Estuary has been in decline for the past several decades. One of the contributing factors is the decreased flow of fresh water reaching the estuary. However, questions remain regarding how this decreased flow impacts the estuary’s overall ecology; in some cases, decreased flow appears to actually improve ecological conditions. 

This study will clarify how variability in water flow and food availability have impacted longfin smelt populations over the past five decades. Leveraging existing datasets from state and federal agencies, the study will examine whether flow-ecology relationships for longfin smelt have changed over time and whether these changes have been consistent across the San Francisco Estuary.

By clarifying what combinations of flow, habitat and prey availability lead to stable populations, this study will inform ongoing conservation efforts for this threatened species.


Principal Investigators
Parsa Saffarinia
University of California, Berkeley