276 P. Goulletquer, G. Bachelet, P. G. Sauriau & P. Noel OPEN ATLANTIC COAST OF EUROPE - A CENTURY OF INTRODUCED SPECIES INTO FRENCH WATERS PHILIPPE GOULLETQUER I ., GUY BACHELET 2 , PIERRE GUY SAURIAU 3 & PIERRE NOEL 4 J Shellfish Aquaculture Research of Poitou-Charentes, IFREMER Ronce Les Bains, La Tremblade, France 2Laboratoire d'Océanographie Biologique, UMR 5805 CNRS, Université Bordeaux l, Station Marine d'Arcachon, Arcachon, France 3CREMA (UMR 10 CNRS-IFREMER), Place du Séminaire, L'Houmeau, France 4Laboratoire de Biologie des Invertébrés marins (ESA CNRS 8044), Mu- séum National d'Histoire Naturelle, Paris, France •Corresponding author Philippe. Gou/letquer@ifremer.fr Abstract This paper aims to establish a comprehensive Iist of exotic species introduced into Atlantic French waters over the last century as weil as their origin, and the vecklrs involved in the process. At least 104 nonindigenous species have been recorded in the Atlantic and Channel coastal wa· ters. Among those species, only a few (Bonamia ostreae, Crepidula fornicata) have resulted in highly significant negative impacts and side-effects on the coastal activity. In contrast, the intro- duction of the Japanese oyster Crassostrea gigas can be considered to be successful, sustaining a large industry counting more than 4,000 companies and 150,000 tons of yearly production. Over the last decade, French and European laws have strenghtened the controls over exotic species introductions, limiting their impacts. These new regulations and increased awareness from the scientific community with regard to coastal industry and biodiversity have reduced significantly the cases of deliberate introduction, while the risk analysis requirement has improved the overall management. However, in spite of these improvements, cases remain significant, mostly by acci- dentai and/or increased vectors of introduction such as the ballast waters and sediment. Moreover, global changes should now be considered as a major issue, Iikely inducing future geographic distribution changes over a large European coastal range. Understanding the invasion population dynamics for exotic species remains a challenging research issue currently addressed by the French INVABIO multidisciplinary program. 1 Introduction Comprehensive reviews of introduced species along the Atlantic coastline and the Eng- lish Channel are not yet available. Although preliminary, attempts were made by Gruet & Baudet (1997) and Belsher et al. (1997), focusing on invenebrates and macroalgae of the Atlantic French waters, respectively. Therefore, the present review represeuts a significant update to this matter, as it includes descriptions of the likely vectors respon- sible for the present situation and species status. This review is likely to be an underes- timate, while multiple introduction vectors are also likely, and only a few cryptogenic species have been detennined (Rosenfield & Mann 1992; Carlton 1996; Reise et al. 1999). Due to its geographic range, biodiversity is particularly high along the Atlantic coasts; e.g., > 3,000 species have been recorded at Roscoff. Most of the introductions (e.g., 276 E. Leppii/wski et al. (eds.), Invasive Aquatic Species of Europe, 276--290. © 2002 Kluwer Academie Publishers. Printed in the Netherlands.