Dt. Zaranko et al., ANOTHER EXOTIC MOLLUSK IN THE LAURENTIAN GREAT-LAKES - THE NEW-ZEALAND NATIVE POTAMOPYRGUS-ANTIPODARUM (GRAY 1843) (GASTROPODA, HYDROBIIDAE), Canadian journal of fisheries and aquatic sciences, 54(4), 1997, pp. 809-814
In 1991, the hydrobiid snail Potamopyrgus antipodarum (Gray 1843), nat
ive to New Zealand, was found 1 km offshore Wilson, New York, in Lake
Ontario. This is the first known occurrence of the snail in eastern No
rth America. Densities of P. antipodarum have increased since its disc
overy, and the snail is expected to spread quickly throughout the Grea
t Lakes area. The biofouling potential of P. antipodarum is probably l
ow; however, its most serious threat may be resource competition with
native molluscs. This species was probably introduced in ballast water
from transoceanic vessels, thus increasing the list of nonindigenous
aquatic organisms introduced into the Great Lakes since the 1800s to 1
40 different organisms. The risk of other species invasions into the G
reat Lakes is still possible, despite the now mandatory ballast water
regulations.