Biological invasions represent a major threat for the health of aquatic ecosystems
worldwide. Most of the alien species are molluscs and crustaceans, with a major
contribution by sessile species. However, many planktonic species are known for their
invading capability. Among copepods, in the last few years the calanoid Pseudodiaptomus
marinus has demonstrated its high invasiveness in the Mediterranean and European
Seas. Since 1950s this species, native to the Indo-Pacific region (Sato, 1913), has
widened its distributional range by colonising several coastal and transitional areas of the Northern and Southern Pacific Ocean. Since 2007, the presence of P. marinus has been documented in European waters as well, with a stable increase in the number of recordings. Several documented primary introduction mechanisms have been documented for this species (aquaculture, mariculture, ballast water and biofouling), whose high invasive potential is supported by specific biological, ecological and behavioural traits. Owing to these characteristics, in some counties P. marinus has been introduced in alert list of species considered potential pests. In addition to its invasive attitude, P. marinus is also indicated as suitable for massive rearing and as target species in ecotoxicological studies.
The main objective of EUROBUS workshop is to organise a meeting aimed at building up an European working group (WG) of scientists and institutions working on P. marinus. The WG will be useful to promote knowledge sharing and sustain international collaborations, and might represent a forum through which monitoring in real time the evolution of the distributional range of this calanoid copepod along European coasts. The WG might benefit from the already existing long-term zooplankton monitoring programmes undertaken by different institutions, as well as from the analysis of the zooplankton samples collected during oceanographic cruises. In addition, the WG might provide a basis to define common protocols for sampling, rearing and experimentation. The workshop would also promote the study of the systematics and taxonomy of this species. As different ecophenotypes are recorded for P. marinus, the meeting would represent a forum to discuss about joint initiative to analyse and compare specimens from different areas of the world integrating molecular and morphological descriptions.