Invasion
Invasion Description
1st Record: Marshfield/MA/Green Harbor (Cape Cod Bay) (1994, McDermott 1998)
Geographic Extent
Marshfield/MA/Green Harbor (Cape Cod Bay) (1994, McDermott 1998; O'Connor 2013); Manomet Point, Plymouth/MA/Cape Cod Bay (1998, Whitlatch and Osman 2000); Sagamore, MA/Cape Cod Bay at the east end of the Cape Cod Canal (1994, McDermott 1998; O'Connor 2013); Welfleet/MA/Cape Cod Bay (1996, McDermott 2000)
Vectors
| Level | Vector |
|---|---|
| Alternate | Ballast Water |
| Alternate | Hull Fouling |
| Alternate | Natural Dispersal |
| Alternate | Canal |
Regional Impacts
| Ecological Impact | Competition | |
| Field sampling shows an overwhelming dominance of Hemigrapsus sanguineus over Carcinus maenas, both in numbers and biomass, at a site near Marshfield (Griffen and Delaney 2007; O'Connor 2013). | ||
| Ecological Impact | Predation | |
| The replacement of C. maenas by H. sanguineus in rocky intertidal regions of Southern New England (Long Island to Cape Ann) has resulted in a likely increase in predation rates, due to much higher population densities of H. sanguineus (results of a field survey near Marshfield) (Griffen and Delaney 2007). | ||