Winter distributions of Dinophysis populations: do they help to predict the onset of the bloom?

• Main Authors: Reguera, Beatriz, Díaz, Patricio Andrés, Escalera-Moura, Laura, Cabanas-López, José Manuel, Ruiz-Villarreal, Manuel
• Other Authors: MacKenzie, L. (Lincoln)
• Format: Book Part
• Language: English
• Published: International Society for the Study of Harmful Algae 2015
• Subjects: Dinophysis distribution; Medio Marino; Centro Oceanográfico de Vigo; overwintering cells; Dinophysis acuminata; Dinophysis acuta; Morena; North Atlantic; Northeast Atlantic
• Online Access: http://hdl.handle.net/10508/9617; http://hdl.handle.net/10261/323446

Blooms of diarrhetic shellfish toxin (DST) producers of the genus Dinophysis (D. acuminata, D. acuta) pose the main threat to the sustainable exploitation of cultivated mussels and other bivalves on the Atlantic coasts of Europe. Dinophysis species do not rely on cysts as a seeding strategy. Detection and evaluation of holoplanktonic populations surviving after bloom decline may be the key to predict the initiation of next year’s bloom. Three cruises were carried out on the NW Iberian shelf in February 2013 (DINVER 2013), January 2006 (DINVER 2006) and May-June 1993 (MORENA 93) to explore winter (D. acuminata) and pre-bloom (D. acuta) distributions of harmful microalgal species. Sampling protocols were adapted to be able to detect extremely low densities (1-5 cells l-1) of Dinophysis species. Potential inoculum populations in retention areas, as previously described for other species in upwelling regions, were not found on these cruises. Here we explore retrospectively data from these cruises, identify hydrodynamic patterns, and accompanying microplanktonic communities, in an attempt to untangle a crucial question in Dinophysis population dynamics: how to predict the initiation of the Dinophysis growth season. ISSHA