NCEAS Project 12122

Evaluation of declines of pelagic organisms in the upper San Francisco Estuary

  • Erica Fleishman

ActivityDatesFurther Information
No activities scheduled at this time.

Abundance indices of four important pelagic fishes in the upper San Francisco Estuary (the low-salinity regions of the San Francisco Bay-Delta and Suisun Bay)-delta smelt, juvenile striped pass, longfin smelt, and delta shad-have been declining since 2001. Delta smelt is an endemic species listed as threatened under both the California and United States Endangered Species acts. Protection of delta smelt often determines water management actions in the estuary, affecting more than 22 million people in California and a multibillion dollar agricultural industry. Longfin smelt also is native to California. Striped bass and threadfin shad both are introduced species, but they support valuable recreational fisheries. Because of the ecological, economic, and political importance of these fishes, there is considerable pressure to find causes of the observed declines and provide information that may help reverse these trends. NCEAS will work with the Interagency Ecological Program (IEP) for the San Francisco Bay / Sacramento - San Joaquin Estuary, a team representing three state, six federal, and one non-governmental organization, and with the CALFED Bay-Delta Program to gain a better understanding of the causes and mechanisms behind the organism declines in the San Francisco Estuary. The project team also aims to place these declines in the broader context of estuarine degradation, organism declines, and approaches to dealing with these problems elsewhere in the nation and world. In particular, we are interested in identifying other systems that might serve as models for how to approach issues in California and ultimately might lead to general principles and lessons for estuarine research and management strategies.

TypeProducts of NCEAS Research
Presentations Fleishman, Erica. 2008. Application of synthetic science to pelagic organism declines in the San Francisco Estuary. California Water Law, Continuing Legal Education Conference, Pasadena, California, 2008. Pasadena, California.
Presentations Fleishman, Erica. 2008. New insights from old data. Interagency Ecological Program Annual Workshop, Pacific Grove, California.
Presentations Mac Nally, Ralph; Thomson, Jim R. 2008. Pelagic organism decline in the San Francisco Estuary: Use of multivariate autoregressive analysis to identify potential causes. Ecological Society of Australia, Sydney.
Report or White Paper Stoms, David M. 2008. Changes in land use in the Sacramento-San Joaquin Bay-Delta region since 1990.