Invasion
Invasion Description
1st Record: Kittery/Maine/Great Bay-Gulf of Maine (1902, Bryant 1906)
Geographic Extent
Kittery/Maine/Great Bay-Gulf of Maine (1902, Bryant 1906); NH/Bunkers Creek, Oyster River, Great Bay (Batchelder 1926); UNH Coastal Marine Lab/Coast Guard Pier, Newcastle/NH/Great Bay (2003, MIT Sea Grant 2003); Odiorne Point/NH/Gulf of Maine (Griffen and Byers 2006; Griffen and Byers 2008; Griffen and Byers 2009)
Vectors
| Level | Vector |
|---|---|
| Alternate | Dry Ballast |
| Alternate | Hull Fouling |
| Alternate | Natural Dispersal |
| Alternate | Ballast Water |
Regional Impacts
| Ecological Impact | Predation | |
| Interactions among crabs of different sizes often result in predation, either among crabs of the same species or different species. Large C. maenas prey on small Hemigrapsus sanguineus and vice versa (Griffen and Byers 2009). Predation, aggression, and interference behavior have the effect of reducing the predation rates of both species when they co-occur. Crabs for these experiments were collected at Odiorne Point, New Hampshire. | ||
| Ecological Impact | Competition | |
| Interference competition and agression occur between Carcinus maenas and Hemigrapsus sanguineus. In experiments, interference between the two species lowered the predation rates of both species on amphipods (Griffen and Byers 2006). Crabs for these experiments were collected at Odiorne Point, New Hampshire. | ||