title: Co-occurrence of the West European (Gr.III) and North American (Gr.I) ribotypes of Alexandrium tamarense (Dinophyceae) in Shetland, Scotland.
abstract: An investigation into the diversity of the dinoflagellate Alexandrium was carried out during August 2007 within two fjordic sea lochs in the Shetland Isles, Scotland. The co-occurrence in the water column of the non-toxic West European (W.E. or Gr.III) and the neurotoxic North American (N.A. or Gr.I) ribotypes of A. tamarense was demonstrated using fluorescent in situ hybridisation. A patch of A. tamarense (W.E.) localised at approximately 10 m depth and extending over 6 km was detected in 'Clift Sound' with concentrations locally reaching approximately 1 x 10(4) cells l(-1). A. tamarense (N.A.) was also observed there but despite the presence of toxins in net haul samples collected locally, concentrations were low and near limits of detection. Alexandrium concentrations were approximately 1.5 x 10(3) cells l(-1) in 'Vaila Sound', where both W.E. and N.A. ribotypes were detected with equal relative abundances in some samples. Given the patchiness of A. tamarense populations and their possible organisation in thin layer structures, better vertical resolution through fine-scale sampling will be necessary for population dynamic studies. Implications for the shellfish industry are substantial since harmful microalgae patches may not be detected during routine monitoring. Moreover, the co-occurrence of morphologically indistinct toxic and non-toxic ribotypes will necessitate implementing molecular methods for their discrimination.
authors.affiliation: The Martin Ryan Institute, National University of Ireland, Galway, Ireland. nicolas.touzet@nuigalway.ie
authors.forename: Nicolas
authors.initials: N
authors.lastname: Touzet
authors.forename: Keith
authors.initials: K
authors.lastname: Davidson
authors.forename: Romain
authors.initials: R
authors.lastname: Pete
authors.forename: Kalen
authors.initials: K
authors.lastname: Flanagan
authors.forename: Gary R
authors.initials: GR
authors.lastname: McCoy
authors.forename: Zouher
authors.initials: Z
authors.lastname: Amzil
authors.forename: Majella
authors.initials: M
authors.lastname: Maher
authors.forename: Annie
authors.initials: A
authors.lastname: Chapelle
authors.forename: Robin
authors.initials: R
authors.lastname: Raine
mesh_terms: D056893:Alveolata / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D044822:Biodiversity; D016172:DNA Fingerprinting; D016054:DNA, Protozoan / Q000235:genetics*; D021521:Ribotyping; D012606:Scotland; D012623:Seawater / Q000469:parasitology*
chemical_list: D016054:DNA, Protozoan