Sacramento-San Joaquin Delta Historical Ecology Study

The San Francisco Estuary Institute/Aquatic Science Center, in collaboration with the Department of Fish and Game, has initiated a historical ecology study of the Sacramento-San Joaquin Delta. The goal is to develop a clear understanding of what the Delta looked like and how it functioned ecologically and hydrogeomorphically prior to significant Euro-American modification.

The historical reconstruction will document, to the extent possible, patterns of variation and extent of habitats throughout the Delta to better understand species support functions and controlling physical processes within the native landscape. Such information will provide a basis for identifying target locations and physical conditions necessary to restore functional habitat mosaics within the projected future Delta landscape. Given the extensive changes to the Delta, the goal of the project is not to create a literal template from which to recreate the historical Delta. Rather the objective is to understand how ecosystem function varied throughout the system in response to identifiable physical gradients (e.g. salinity, tidal range), to inform the large scale restoration strategies being considered.

Historical analysis has been an important tool for large wetland ecosystem restoration efforts in the U.S. (e.g. South Florida, Puget Sound). In these regions, historical reconstructions have enabled scientists and managers to identify practical strategies for ecosystem management within highly disturbed systems. Similar studies in the Bay Area and coastal California have led to a wide range of important insights into the complex systems we seek to enhance. While there has been some excellent prior historical research in the Delta (e.g. Brian Atwater, The Bay Institute), a tremendous amount of compelling historical information has not yet been compiled or synthesized.