Invasion
Invasion Description
1st Records: Napa/CA/Napa Oreek (1874, Smith 1895, 73 fish from Lake Champlain, VT, fishe out); Union City/CA/Alameda Creek (1874, Smith 1895, 12 fish from Michigan, established populaiton);
Additonal stockings occurred in 1879 and 1889-1895 in the San Francisco estuary watershed, and in many other Calfornia watersheds (Smith 1895; Dill and Cordone 1977).
Geographic Extent
CA/Sacramento-San Joaquin Delta (Wang 1986; Cohen and Carlton 1995; Dill and Cordone 1997; Moyle and Randall 1999, rare in Delta, mostly in dead-end sloughs); Walnut Grove/CA/North Fork Mokelumne River (Cavallo et al. 2012); CA/Napa River (Leidy 2007, locally common); CA/Alameda Creek (Leidy 2007, locally common); CA/San Lorenzo, Coyote creeks,; Guadalupe Rivers (Leidy 2007)
Vectors
| Level | Vector |
|---|---|
| Probable | Fisheries Intentional |
Regional Impacts
| Economic Impact | Fisheries | |
Smallmouth Bass have minor, localized importance as a sport fish in California (Dill and Cordone 2007) | ||
| Ecological Impact | Predation | |
| In California, predation by Smallmouth Bassu was correlated with a decline in the native cyprinid Mylodon conocephalus (Hardhead), and may have had adverse effects on other native species (Dill and Cordone 1997). | ||