Invasion
Invasion Description
1st record: Essex/England/Crouch Estuary (1920, Cole 1940; Eno 1997; Gibbs et al. 1991)
n the 1980s, populations of U. cinerea declined drastically, bringing populations in several estuaries close to extinction. The cause appears to be tributyltin TBT) pollution from anti-fouling paint, resultin in imposex- malformation of male and female reproductive organs. Laws curtailing the use of TBT may permit a recovery of U. cinera and native mollusks (Gibbs et al. 1991).
Geographic Extent
Essex & Kent/England/Crouch Estuary (1929, Cole 1942; Eno 1997); Essex/Blackwater Estuary (Eno 1997); Frinton, Essex to Herne Bay Kent/England/English Channel estuaries( Gibbs et al. 1991). Whitstable/England/Thames Estuary (Cole 1942, no longer present, Eno 1997); Gorishoek/Netherlands/Oosterschelde (2007, Faase and Ligthart 2009, established but very localized); Stavenisse/Netherlands/Oosterschelde (2007, Faase and Ligthart 2009); Tuttelhoek/Netherlands/Oosterschelde (2007, Faase and Ligthart 2009); Bergse Diep/Netherlands/Oosterschelde (2007, Faase and Ligthart 2009)
Vectors
| Level | Vector |
|---|---|
| Probable | Oyster Accidental |
Regional Impacts
| Ecological Impact | Competition | |
| Since its discovery in estuaries of Essex and Kent, U. cinerea largely replaced the native oyster drill (Ocenebra erinacea) in the 1930s-50s. Some of the American drill's success was apparently due to its greater tolerance of severe winters, which killed many of the native snails (Cole 1942). Now, both species are rare because of imposex, caused by tributlytin (TBT) pollution (Gibbs et al. 1991). | ||
| Economic Impact | Fisheries | |
| Urosalpinx cinerea was regarded as a major pest when it began infesting beds of the European Oyster (Ostrea edulis) in England. Its biggest effect was on recruitment, since U. cinerea mostly consumes spat. Fishermen used a variety of methods, from hand-picking and dredging, in an attempt to limit drill predation (Cole 1942). | ||
| Ecological Impact | Predation | |
| Urosalpinx cinerea, in English oyster-beds, fed mostly on spat of European Oysters (Ostrea edulis). Spat of about 10 cm were preferred to smaller spat, adult oysters, or to mussels (Cole 1942). | ||