摘要：In the Dutch province of Zeeland, fouling species on a mussel line form a diverse assemblage of mainly exotic evertebrate species. This differs strikingly from the situation in the estuaries of eastern Prince Edward Island, Canada. Despite the fact that about the same species are present, monocultures of exotic tunicate species dominate there. The import of mussels has been strictly regulated in The Netherlands, aiming at a reduction of the introduction of invasive species among which tunicates.
