Invasion
Invasion Description
1st Record: CA/Tomales Bay (1st planted 1928, Barrett 1963, cited by Carlton 1979, occasional reproduction observed, 1974, Span 1978, commercial operations continue to present, Conte 1996)
Geographic Extent
CA/Tomales Bay (1st planted 1928, Barrett 1963, cited by Carlton 1979, occasional reproduction observed, 1974, Span 1978, commercial operations continue to present, Conte 1996)
Vectors
| Level | Vector |
|---|---|
| Probable | Oyster Intentional |
Regional Impacts
| Economic Impact | Fisheries | |
| Commercial oyster operations, using M. gigas began in Tomales Bay in 1928, and continue to the present. Oyster culture here was intially dependent on seed imported from Japan, but now uses seed produced in US hatcheries (Barrett 1963; Conte 1996). | ||
| Ecological Impact | Parasite/Predator Vector | |
| Parasite-Predator vector- Although M. gigas has not become definitely established in Tomales Bay, its introduction has been a possible/probable vector for a number of oyster foulers or predators, including Pteropurpura (=Ocinebrellus) inornata (Japanese Oyster Drill), the parasitc copepod Mytilicola orientalis (widespread), the mussel Musculista senhousia, the bryozoan Schizoporella japonica, and the tunicates Botrylloides violaceus, Didemnum vexillum, and Styela clava (Carlton 1979; Cohen and Carlton 1995). | ||