FN Archimer Export Format PT C TI Investigating an avian source of shellfish faecal contamination in the Thau lagoon (the Mediterranean, France) OT Étude d'une source de contamination fécale d'origine aviaire des coquillages de l'étang de Thau (Méditerranée, France) BT AF DEROLEZ, Valerie SERAIS, Ophelie CAPRAIS, Marie-Paule LE SAUX, Jean-Claude MESSIAEN, Gregory AS 1:;2:;3:;4:;5:; FF 1:PDG-DOP-LER-LERLR;2:PDG-DOP-LER-LERLR;3:PDG-DOP-DCN-EMP-MIC;4:PDG-DOP-DCN-EMP-MIC;5:PDG-DOP-LER-LERLR; SI SETE BREST SE PDG-DOP-LER-LERLR PDG-DOP-DCN-EMP-MIC UR https://archimer.ifremer.fr/doc/00025/13593/10659.pdf LA English DT Proceedings paper DE ;Escherichia coli;origine aviaire;coquillage;contamination fécale;étang de Thau;oiseau de mer;bactériophage;dépistage de la source microbienne;temps sec;Escherichia coli;avian source;shellfish;faecal contamination;Thau lagoon;seabird;bacteriophage;microbial source tracking;dry weather AB Microbes regularly contaminate Thau lagoon shellfish. Between 1997 and 2007, 18% of the analyses carried out in dry weather recorded more than 230 Escherichia coli / 100 g of bivalves (Ifremer French microbial monitoring network), leading the administration to restrict the shellfish harvest area, including suspension of production. This study aims to determine, the contribution of seabirds, which roost at night on the Thau lagoon shellfish growing frames, to shellfish faecal pollution in dry weather.Data were collected in 2008 from both the drainage area (pollution input) and the lagoon (water quality and microbial monitoring, seabird counts) in dry weather. The data showed that, with no watershed input or lagoon resurgence, microbial contaminants were present in shellfish under oyster farming structures used by seabirds, particularly at night, as roosting areas. Shellfish contamination levels were higher under roosting areas than under control structures. Initial results of F+ specific RNA bacteriophage genotyping in shellfish samples suggested contamination of animal origin. PY 2009 PD JUL CT 7th International Conference on Molluscan Shellfish Safety, 14-19 June 2009 ID 13593 ER EF