in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Dominant [details]
in Celtic Sea (IHO Sea Area) : Common [details]
in English Channel (IHO Sea Area) : Common [details]
in North Sea (IHO Sea Area) : Common [details]
in United Kingdom part of the English Channel (Marine Region) : Common [details]
in Canadian part of the Bay of Fundy (Marine Region) : Rare to common [details]
in North Sea (IHO Sea Area) : Rare to common [details]
United Kingdom part of the Irish Sea and St. George's Channel (Marine Region): Locally common [details]
in Celtic Sea (IHO Sea Area) : Rare [details]
in Aegean Sea (IHO Sea Area) : Common [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Common [details]
in Mediterranean Sea - Western Basin (IHO Sea Area) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in Mediterranean Sea - Western Basin (IHO Sea Area) : Loss of public/tourist amenity [details]
in Mediterranean Sea - Western Basin (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in South China Sea (IHO Sea Area) : Alters bio-geochemical/hydrologic cycles [details]
in South China Sea (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Romanian part of the Black Sea : Human health [details]
in Adriatic Sea (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in North Sea (IHO Sea Area) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in Sweden (Nation) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Genetic impacts: hybridisation and introgression [details]
in Hawaiian part of the North Pacific Ocean (Marine Region) : Adverse habitat modification [details]
in Hawaiian part of the North Pacific Ocean (Marine Region) : Water abstraction or nuisance fouling [details]
in The Coastal Waters of Southeast Alaska and British Columbia (IHO Sea Area) : Adverse habitat modification [details]
in Black Sea (IHO Sea Area) : Alters trophic interactions [details]
in North Atlantic Ocean (IHO Sea Area) : Water abstraction or nuisance fouling [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Baltic Sea (IHO Sea Area) : Water abstraction or nuisance fouling [details]
in North Sea (IHO Sea Area) : Water abstraction or nuisance fouling [details]
in United States (Nation) : Outcompetes native species for resources and/or space [details]
in Aegean Sea (IHO Sea Area) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in Aegean Sea (IHO Sea Area) : Pathogen/parasite or carrier of a pathogen/parasite [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Pathogen/parasite or carrier of a pathogen/parasite [details]
in North Sea (IHO Sea Area) : Alters bio-geochemical/hydrologic cycles [details]
in Australia (Nation) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in Australia (Nation) : Water abstraction or nuisance fouling [details]
in New Zealand (Nation) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in New Zealand (Nation) : Water abstraction or nuisance fouling [details]
in Aegean Sea (IHO Sea Area) : Loss of public/tourist amenity [details]
in North Sea (IHO Sea Area) : Adverse habitat modification [details]
in Norway (Nation) : Adverse habitat modification [details]
in Norway (Nation) : Alters bio-geochemical/hydrologic cycles [details]
in Black Sea (IHO Sea Area) : Other impact - undefined or uncertain [details]
in North Atlantic Ocean (IHO Sea Area) : Other impact - undefined or uncertain [details]
in North Sea (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Ukraine (Nation) : Adverse habitat modification [details]
in United Kingdom (Nation) : Loss of aquaculture/commercial/recreational harvest or gain [details]
in United Kingdom part of the English Channel (Marine Region) : Adverse habitat modification [details]
in South Atlantic Ocean (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Caribbean Sea (IHO Sea Area) : Adverse habitat modification [details]
in Caribbean Sea (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Baltic Sea (IHO Sea Area) : Consumes native species (predator or herbivore) [details]
in Baltic Sea (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in North Atlantic Ocean (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Norway (Nation) : Outcompetes native species for resources and/or space [details]
in Aegean Sea (IHO Sea Area) : Water abstraction or nuisance fouling [details]
in North Sea (IHO Sea Area) : Alters trophic interactions [details]
in Aegean Sea (IHO Sea Area) : Human health [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Human health [details]
in The Coastal Waters of Southeast Alaska and British Columbia (IHO Sea Area) : Alters bio-geochemical/hydrologic cycles [details]
in The Coastal Waters of Southeast Alaska and British Columbia (IHO Sea Area) : Consumes native species (predator ... [details]
in Mediterranean Sea - Western Basin (IHO Sea Area) : Adverse habitat modification [details]
in Aegean Sea (IHO Sea Area) : Other impact - undefined or uncertain [details]
in Ionian Sea (IHO Sea Area) : Other impact - undefined or uncertain [details]
in Mediterranean Sea - Eastern Basin (IHO Sea Area) : Other impact - undefined or uncertain [details]
in Mediterranean Sea - Western Basin (IHO Sea Area) : Other impact - undefined or uncertain [details]
in Celtic Sea (IHO Sea Area) : Other impact - undefined or uncertain [details]
in North Sea (IHO Sea Area) : Other impact - undefined or uncertain [details]
in Aegean Sea (IHO Sea Area) : Outcompetes native species for resources and/or space [details]
in Turkey (Nation) : Alters trophic interactions [details]
in United States (Alaska) part of the Gulf of Alaska (Marine Region) : Outcompetes native species for resources ... [details]
in Aegean Sea (IHO Sea Area) : Alters trophic interactions [details]
in California (State) : Other impact - undefined or uncertain [details]