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Updated: May 11, 2026

Methods for Image-based Surveys of Benthic Macroinvertebrates and Their Habitat Exemplified by the Drop Camera Survey for the Atlantic Sea Scallop
Published on: July 2, 2018
Benthic macrofaunal assemblages of the San Francisco Estuary and Delta, USA
Bruce Thompson1, J Ananda Ranasinghe, Sarah Lowe
1San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804, USA. brucet@sfei.org
Abstract:
The spatial and temporal distribution of macrobenthic assemblages in the San Francisco Estuary and Sacramento-San Joaquin River Delta were identified using hierarchical cluster analysis of 501 samples collected between 1994 and 2008. Five benthic assemblages were identified that were distributed primarily along the salinity gradient: (1) a polyhaline assemblage that inhabits the Central Bay, (2) a mesohaline assemblage that inhabits South Bay and San Pablo Bay, (3) a low-diversity oligohaline assemblage primarily in Suisun Bay, (4) a low-diversity sand assemblage that occurs at various locations throughout the Estuary, and (5) a tidal freshwater assemblage in the Delta. Most sites were classified within the same assemblage in different seasons and years, but a few sites switched assemblage designations in response to seasonal changes in salinity from freshwater inflows.
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