# | Species | Year | Period | From - To | Reason | Established in the wild | Ref. no. |
1 | Gammarus tigrinus | 1931 | 1925-1949 | Western North Atlantic - Britain | ballast water | Unknown | 003224 |
2 | Hyas araneus | 1986 | 1975-present | Northern Hemisphere - King George Island | accidental with ships | 087513 |