| Algae | Bonnemaisonia hamifera | 1994 | Definite | Established | Ballast Water, Hull Fouling |
| Tunicates | Botrylloides violaceus | 2004 | Definite | Established | Hull Fouling |
| Crustaceans-Crabs | Carcinus maenas | 1951 | Definite | Established | Ballast Water, Hull Fouling, Natural Dispersal |
| Tunicates | Ciona intestinalis | 1868 | Definite | Established | Hull Fouling |
| Algae | Codium fragile ssp. Fragile | 1995 | Definite | Established | Ballast Water, Fisheries Accidental (not Oyster), Hull Fouling |
| Crustaceans-Amphipods | Corophium volutator | 1977 | Definite | Established | Ballast Water, Dry Ballast |
| Platyhelminthes | Cryptocotyle lingua* | 1972 | Definite | Established | Dry Ballast, Fisheries Accidental (not Oyster), Fisheries Intentional, Hull Fouling, Natural Dispersal |
| Cnidarians-Anthozoans | Diadumene lineata | 2004 | Definite | Established | Hull Fouling |
| Tunicates | Didemnum vexillum | 2005 | Definite | Established | Hull Fouling |
| Algae | Dumontia contorta* | 1997 | Definite | Established | Ballast Water, Hull Fouling, Natural Dispersal |
| Mollusks-Gastropods | Duvaucelia plebeia | 2013 | Definite | Established | None |
| Annelids-Polychaetes | Hediste diversicolor | 1963 | Definite | Established | Ballast Water, Dry Ballast |
| Mollusks-Gastropods | Littorina littorea | 1862 | Definite | Established | Ballast Water, Hull Fouling, Natural Dispersal |
| Algae | Melanosiphon intestinalis* | 1996 | Definite | Established | Fisheries Accidental (not Oyster), Hull Fouling, Natural Dispersal |
| Mollusks-Gastropods | Myosotella myosotis | 1873 | Definite | Established | Dry Ballast |
| Crustaceans-Amphipods | Orchestia gammarellus | 1864 | Definite | Established | Dry Ballast |
| Arthropoda-Insects | Petrobius brevistylis* | 1967 | Definite | Established | Dry Ballast, Hull Fouling |
| Crustaceans-Mysids | Praunus flexuosus | 2004 | Definite | Established | Ballast Water |
| Tunicates | Styela canopus | 2004 | Definite | Established | Hull Fouling |