The sighting of the brush-clawed shore crab Hemigrapsus takanoi on the western coast of northern Cotentin confirms the extension of this species into the western part of the English Channel. This new sighting remains enigmatic because the Normanno-Breton Gulf circulation patterns do not appear to promote natural transport of crab larvae from the Atlantic or from the eastern part of the English Channel. It has been suggested that the professional oyster transport could be the origin of this species' presence on this part of the French coast.