Invasion
Invasion Description
1st record: Halifax /Nova Scotia/Atlantic Ocean (Ganong 1887)
Geographic Extent
Newfoundland/Conception Bay (Bequaert 1943); Placentia/Newfoundland/Placentia Bay (1947, USNM 592331, US National Museum of Natural History 2007); Baddeck, Cape Breton Island/Bras d'Or Lake (USNM 123326, late 1800s, US National Museum of Natural History 2007, W. H. Dall collector); Cape Breton Island, North Ingonish/Nova Scotia/Bras d'Or Lake (MCZ 192670, Museum of Comparative Zoology 2008); North Sydney/Nova Scotia/Sydney Harbour (Blakeslee et al. 2008; 2008, Choi et al. 2016); Scatarie Island, off Cape Breton Island/Nova Scotia/Atlantic Ocean (White et al. 2010); Mulgrave/Nova Scotia/Strait of Canso (Blakeslee et al. 2008); Marie Joseph Park/Nova Scotia/Atlantic Ocean (Blakeslee et al. 2008); Halifax /Nova Scotia/Atlantic Ocean (1857, Ganong 1887; Blakeslee et al. 2008; 2008, Choi et al. 2016); 18 mi. E.S.E. of Halifax, Lawrencetown/Nova Scotia/Atlantic Ocean (MCZ 229355, Museum of Comparative Zoology 2008); North Boundary Queensland/Nova Scotia/Outlet Of Tidal Creek, Atlantic Ocean (USNM 664591, US National Museum of Natural History 2007); Nova Scotia/Mersey River (1959, USNM 657040, US National Museum of Natural History 2007)
Vectors
| Level | Vector |
|---|---|
| Probable | Natural Dispersal |
| Alternate | Hull Fouling |
| Alternate | Dry Ballast |
Regional Impacts
| Ecological Impact | Herbivory | |
| Grazing by Littorina littorea may control the recruitment of Codium fragile ssp. fragile in the upper intertidal, where this alga is also stressed by ultraviolet, freezing, and dessication. Grazing by L. littorina has less effect in the lower intertidal, where Codium suffers less damage and grows at a faster rate (Scheibling et al. 2008) | ||
| Ecological Impact | Parasite/Predator Vector | |
| The introduction of Littorina littorea to the Northwest Atlantic is believed to have also introduced the digenean trematode Cryptocotyle lingua. Common Periwinkles, collected at 4 sites on the Atlantic coast of Maritime Canada, were infected with C. lingua (Blakeslee and Byers 2008). The rediae (first parasitic stages) have infected not only L. littorea, but also native populations of L. saxatilis (Rough Periwinkle) and L. obtusata (Smooth Periwinkle) (Blakeslee and Byers 2008; Blakeslee et al. 2008). The trematodes cause extensive damage to the host's digestive and reproductive systems (Wood et al. 2009). The rediae of C. lingua metamorphose into cercariae, which have a swimming tail and infect fishes (Stunkard 1930; Sindermann et al. 1962). When infected fish are eaten by birds or mammals, the metacercariae grow in the final host's digestive tract and and reproduce (Stunkard 1930; Sindermann et al. 1962). Thus, the introduction of the Common Periwinkle has added a new parasite to 3 trophic levels. | ||