Invasion
Invasion Description
1st Record: Shelter Cove/CA/Pacific Ocean (1995, Rawson et al. 1999). In 2005-2007, the frequency of M. galloprovincialis and hybrids declined from ~60-70% in 1995 to about 5% in 2005-2007. This change was attributed to lower temperatures, resulting from the Pacific Decadal Oscillation (Hilbish et al. 2010).
Geographic Extent
Mendocino/CA/Pacific Ocean (1995, Rawson et al. 1999, molecular survey); Shelter Cove/CA/Pacific Ocean (1995, Rawson et al. 1999)
Vectors
| Level | Vector |
|---|---|
| Alternate | None |
| Alternate | Natural Dispersal |
Regional Impacts
| Ecological Impact | Competition | |
| In 1994-1995, purebred M. galloprovincialis comprised ~50% of the mussels sampled at Shelter Cove, compared to about ~30% for purebred M. trossulus (Rawson et al. 1999). However, the percentage decline to ~5% by 2005-2007, apparently because of lower temperatures resulting from the Pacific Decadal Oscillation, made M. galloprovincialis less competitive (Hilbish et al. 2010). | ||
| Ecological Impact | Hybridization | |
| In 1994-1995, M. galloprovincialis X M. trossulus hybrids comprised 12-20% of the mussels at Shelter Cove. In 2005-2007, the frequency of hybrids declined sharply, to about 1-2% (Hilbish et al. 2010), apparently due to lower temperatures resulting from the Pacific Decadal Oscillation, making M. galloprovincialis less competitive (Hilbish et al. 2010). | ||