Invasion
Invasion Description
1st Record: Bodega Head/CA/Pacific Ocean (1995, Rawson et al. 1999). In 2005-2007, the frequency of M. galloprovincialis and hybrids declined from 70% to about 55%. This change was attributed to lower temperatures, resulting from the Pacific Decadal Oscillation (Hilbish et al. 2010).
Geographic Extent
Gualala Point/CA/Pacific Ocean (1995, Rawson et al. 1999); Bodega Head/CA/Pacific Ocean (1995, Rawson et al. 1999);
Vectors
| Level | Vector |
|---|---|
| Alternate | Ballast Water |
| Alternate | Hull Fouling |
Regional Impacts
| Ecological Impact | Competition | |
| In 1994-1995, at Gualala Point and Bodega Head, purebred M. galloprovinialis comprised 42-45% of the mussels sampled, compared to 40-44% of native M. trossulus (Rawson et al. 1999). Changing environmental conditions (declining water temperatures) due to climate cycles, have probably reduced the frequency of M. galloprovincialis (Braby and Somero 2006; Hilbish et al. 2010). | ||
| Ecological Impact | Hybridization | |
| Mytilus galloprovincialis X M. trossulus hybrids comprised 14% of total mussels sampled in a 1994-1995 survey (Rawson et al. 1999). | ||