| Nematodes | Anguillicola crassus* | 2005 | Definite | Established | Fisheries Accidental (not Oyster), Natural Dispersal |
| Crustaceans-Crabs | Carcinus maenas | 1909 | Definite | Established | Ballast Water, Dry Ballast, Hull Fouling, Natural Dispersal |
| Algae | Colpomenia peregrina* | 2011 | Definite | Established | Hull Fouling |
| Crustaceans-Amphipods | Corophium volutator | 1934 | Definite | Established | Ballast Water, Dry Ballast |
| Crustaceans-Crabs | Hemigrapsus sanguineus | 2008 | Definite | Established | Hull Fouling, Natural Dispersal |
| Mollusks-Gastropods | Littorina littorea | 1873 | Definite | Established | Ballast Water, Hull Fouling, Natural Dispersal |
| Bryozoans | Membranipora membranacea | 1998 | Definite | Established | Ballast Water, Hull Fouling, Natural Dispersal |
| Mollusks-Bivalves | Teredo navalis | 1960 | Definite | Established | Hull Fouling |