The collapse of pelagic fishes in the upper San Francisco estuary

By: , and 



Although the pelagic fish community of the upper San Francisco Estuary historically has shown substantial variability, a recent collapse has captured the attention of resource managers, scientists, legislators, and the general public. The ecological and management consequences of the decline are most serious for delta smelt (Hypomesus transpacificus), a threatened species whose narrow range overlaps with large water diversions that supply water to over 25 million people. The decline occurred despite recent moderate hydrology, which typically results in at least modest recruitment, and investments of hundreds of millions of dollars in habitat restoration and environmental water allocations to support native fishes. In response to the pelagic fish collapse, an ambitious multi-hyphen;agency research team has been working since 2005 to evaluate the causes of the decline, which likely include a combination of factors: stock-recruitment effects, a decline in habitat quality, increased mortality rates, and reduced food availability due to invasive species.

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Publication type Article
Publication Subtype Journal Article
Title The collapse of pelagic fishes in the upper San Francisco estuary
Series title Fisheries
DOI 10.1577/1548-8446(2007)32[270:TCOPFI]2.0.CO;2
Volume 32
Issue 6
Year Published 2007
Language English
Publisher Taylor & Francis
Contributing office(s) California Water Science Center
Description 8 p.
First page 270
Last page 277
Country United States
State California
Other Geospatial Upper San Francisco Estuary
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