Recent invasion of the Japanese oyster drill along the French Atlantic coast: identification of specific molecular markers that differentiate Japanese, Ocinebrellus inornatus, and European, Ocenebra erinacea, oyster drills

¹ Laboratoire de Biologie et Environnement Marins (LBEM), Université de la Rochelle, Avenue Michel Crépeau, 17042 La Rochelle cedex, France
² IFREMER, Shellfish Aquaculture Research Laboratory (LCPC), Ronce-les-Bains, 17320 La Tremblade, France
³ Centre de Recherche en Écologie Marine et Aquaculture (CREMA), UMR 10 CNRS-IFREMER, place du Séminaire, BP 5, 17137  L’Houmeau, France

Received: 5 June 2001
Accepted: 30 October 2001

Abstract

The direct amplification of length polymorphism technique (DALP) has been used to distinguish species-specific banding patterns in two marine gastropod oyster drills Ocenebra erinacea (Linnaeus, 1758) and Ocinebrellus inornatus (Récluz, 1851). Ocenebra erinacea is the European oyster drill, common along all European coasts. Ocinebrellus inornatus, the Japanese oyster drill, was recorded in oyster growing areas of the Marennes-Oléron Bay (SW France) for the first time in 1995. This new biological invasion could lead to an increase, which must be evaluated, in the predation risk for cultivated species i.e. oysters and blue mussels, and for littoral fishing resources along the French Atlantic coasts. As a result, since specific identification of early life stages of both species (egg capsules and juveniles) was previously found to be both difficult and unsure using only morphological criteria, four Ocenebra erinacea and two Ocinebrellus inornatus specific molecular markers were identified and sequenced. These markers will facilitate the assessment of respective ecological impacts (reproductive patterns, abundance and spatial distribution of juveniles), resulting from the exotic species versus the native species and will allow us to analyse with certainty demographic profiles of the two oyster drill populations.