CRR number 334 – 'Status of introductions of non-indigenous marine species to the North Atlantic and adjacent waters 2003–2007' – brings together and summarizes all observations of such species that were reported annually by ICES Working Group on Introductions and Transfers of Marine Organisms (WGITMO) over the given period. The records are aimed at assisting the efforts of countries in preventing, managing, controlling non-indigenous organisms, as well as building an understanding of the organisms that may disperse from one country to another.
The incidences documented are of five taxonomic groups: pathogens, phytoplankton, algae and plants, invertebrates, and fish, recorded in coastal, marine, and brackish areas. For each group, information is organized by region, primarily the northeast and northwest Atlantic, Baltic, and Mediterranean. This is intended to provide insight into the species' distribution and dispersal. Several species of algae, crustaceans, and molluscs were the most problematic. Taxonomic identification, particularly of small organisms, remains challenging, but is critical in identifying and thus managing these species.
The intentional or accidental introduction of non-indigenous marine species can have serious ecological and economic impacts, contributing to the global loss of biodiversity, negatively affecting coastal communities, and potentially impacting on human health.