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USGS Scientists Study Habitat Features in the San Francisco Estuary to Better Inform Conservation Efforts for Aquatic Species

November 4, 2021

The Pacific coast of the lower 48 US states (Washington, Oregon, and California) has over 400 estuaries of various types. The largest of these is the San Francisco Estuary (San Francisco Bay and Delta) in California.

USGS researcher holding striped bass
A USGS researcher holds a large striped bass (Morone saxatilis). Striped bass were one of the species modeled in the study.

Due to human activity, over 90% of tidal wetland habitat in San Francisco Estuary has been lost. One impact of this loss is its effect on fish and other aquatic organisms. Estuaries are dynamic transitional ecosystems which provide important habitat for aquatic life. Conservation of these species requires knowledge of estuarine features which drive their abundance and distribution.

In an article published in the journal Marine and Coastal Fisheries, California Water Science Center fish biologist, Frederick Feyrer and others discuss how the habitat features of the San Francisco estuary impact populations of aquatic species. In the research leading to the article, USGS scientists studied how stationary and dynamic habitat features of the San Francisco estuary impact populations of aquatic species.  Key findings demonstrated how stationary physical habitat features interact with hydrodynamics and dynamic water quality conditions across varying spatio-temporal scales to drive fish species distribution and abundance.   Most of the species observed, especially native species of special management interest, were associated with tidal wetland habitat.  This suggests that restoration of tidal wetlands is likely an effective conservation tool for native fish species.

To learn more, read the article: Disentangling Stationary and Dynamic Estuarine Fish Habitat to Inform Conservation: Species-Specific Responses to Physical Habitat and Water Quality in San Francisco Estuary.