Invasion
Invasion Description
1st Record: Woods Hole/MA/Buzzards Bay-Vineyard Sound (1875, Gray 1879, cited by Gray 1897)
Geographic Extent
Woods Hole/MA/Buzzards Bay-Vineyard Sound (1875, Gray 1879, cited by Ganong 1897, only 2 shells found in 1875, abundant in 1876); Massachusetts Maritime Academy, Bourne/MA/Buzzards Bay (2000, MIT Sea Grant 2007); Cape Cod, Bourne, Wing's Neck/MA/Buzzards Bay (MCZ 182310, Museum of Comparative Zoology 2008); Cape Cod, Bourne, Monument Beach/MA/Buzzards Bay (MCZ 182311, Museum of Comparative Zoology 2008); Old Silver Beach, N of Falmouth/MA/ Buzzard's Bay (MCZ 201361, Museum of Comparative Zoology 2008); South Dartmouth, Sta 1839/MA/MCZ 211135, Museum of Comparative Zoology 2008)
Vectors
| Level | Vector |
|---|---|
| Alternate | Natural Dispersal |
| Alternate | Hull Fouling |
| Alternate | Dry Ballast |
Regional Impacts
| Ecological Impact | Competition | |
| In the Woods Hole area, from 1900 to 1930, Littorina littorea was observed to gradually exclude Ilyanassa obsoleta from cobble shores and wood pilings, and increasingly invading marshes, largely confining I. obsoleta to mudflats (Dimon 1905; Clench 1930, cited by Brenchley and Carlton 1983). However, experimental studies of the mechanisms of competition were not conducted in this region, to our knowledge. In experimental cage manipulations at Nobska Point and Gansett Beach, Woods Hole, MA L. littorea depressed the growth of L. saxatilis (Rough Periwinkle) in the lower intertidal zone, probably due to food competition. However, this effect was not seen in the upper intertidal zone, where L. saxatilis is more abundant (Yamada and Mansour 1987). | ||