Invasion
Invasion Description
1st Record: Sausalito/CA/San Francisco Bay (Richardson 1898, cited by Carlton 1979)
Geographic Extent
Sausalito/CA/San Francisco Bay (Richardson 1898, cited by Carlton 1979); CA/San Pablo Bay (1912, USNM 64473, United States Museum of Natural History 2007; Graening and Rogers 2013); Rodeo/CA/San Pablo Bay (1939, Barrows 1939, cited by Carlton 1979); China Camp/CA/San Pablo Bay (2005, Robinson et al. 2011); cargo ship 'Florikan'/CA/Suisun Bay (Llanso et al. 2011); Oakland/CA/Lake Merritt (Light 1961, cited by Carlton 1979; USNM 250154, 1989, United States Museum of Natural History 2007); Point Richmond.CA/San Francisco Bay (Light 1961, cited by Carlton 1979); Dumbarton-Cut-off/CA/South San Francisco Bay (1920, USNM 89805, 1989, United States Museum of Natural History 2007); Antioch/CA/Suisun Bay (Koifoid and Miller 1927, cited by Cohen and Carlton 1995); CA/Grizzly Bay near Suisun Slough (Graening and Rogers 2013)
Vectors
| Level | Vector |
|---|---|
| Probable | Hull Fouling |
Regional Impacts
| Economic Impact | Shipping/Boating | |
| Sphaeroma quoianum burrows into the walls of marsh channels and levees, contributing to erosion, increasing flood threats, and damaging Styrofoam floats in marinas. However, the extent of this damage has not been quantified (Carlton 1979; Cohen and Carlton 1995). Damage to plastic floats was extensive in San Francisco Bay and Elkhorn Slough, CA (Davidson 2012). | ||
| Ecological Impact | Habitat Change | |
| Sphaeroma quoianum burrows into the walls of marsh channels, contributing to erosion, and modifying marsh habitat. Higgins (cited by Davidson 2008) observed that this isopod increased the erosion of sandstone terraces in San Francisco Bay. Carlton (1979) suggested that the isopod was responsible for the loss of 'tens of scores of meters of shoreline since the 19th century'. | ||