American lobsters on the lam may constitute an ecological threat to its European cousins, experts say
After more than a dozen findings along the Norwegian coast and an American lobster (Homarus americanus) was caught off Lysekil on the Swedish Skagerrak Coast last fall, the Swedish Board of Fisheries offered an award for anyone handing in a suspect lobster.
The American lobster is seen as a possible threat to the European lobster (Homarus gammarus), since it may carry contagious diseases earlier unknown to the European species. One such is gaffkemia, a bacterial disease that may cause up to 100 per cent mortality within a week if the European lobster catches it.
Eight lobsters were submitted to the Institute of Marine Research at Lysekil, four of which proved to be of the American type. This was established after DNA analysis – since there are great variations in appearance within the two species, it is often difficult to determine which is which from just inspecting them.
Since all four had rubber bands around one or both claws, it is believed that they had fled from holding cages. It is illegal in Sweden to keep lobster in holding cages in the sea, or letting them loose, and the findings have been reported to the police.
Some 150 tons of live American lobster are imported to Sweden annually, and Board of Fisheries experts now point out that as long as such imports are allowed, there is a risk that they are spread to Swedish waters from sheer lack of knowledge.
They added that they thought it is now time for Sweden and other member nations to act in the European Union to prevent the American lobster from spreading to European waters.