| dc.description.abstract | Around 1940, the polychaete ragworm Hediste diversicolor (Muller, 1776) (formerly Nereis diversicolor) was imported to Caspian Sea from the Azov Sea in the Berdyansk region (Ukraine ). Soon the species became established over a large area along the Caspian Sea coast. Then, after 1995, the species was found at offshore oil production locations approximately 30 km off the coast. The questions are: bow did the species spread out to the offshore locations, and could this colonisation at the offshore locations possibly represent any environmental concern? The present report includes a brief review of the available knowledge related to the biology of this ragworm species. Our objective is to provide a collection of knowledge which can assist the process of addressing the above noted questions. Based on the reviewed information we also suggest in short bow this topic should be approached in terms of practical surveys. I.e., the very first topic which needs to be clarified is whether or not H. diversicolor populations are present in the area between the shore locations and the offshore platform locations. Since the species has a lirnited dispersal capacity a gap in presence would indicate that the dispersal out to the offshore locations has been assisted by human actions, and we would in that case initially consider ballast water in tankers to be the most likely vehicle for species dispersal. Furthermore, a full elucidation of such a dispersal process is possible, and would best be obtained by means of using analyses of population specific molecular markers in representative polychaete samples collected from each of the populations studied (offshore and coastal). Lists of expert and expert laboratories which have competence within these analyses are included in the present report. | en_US |
