12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006fragilis was found from June toSeptember coinciding with mucilagephenomena. Towards the end ofsummer, Gonyaulax cells wereoften found inside aggregationsalong with diatoms and heliozoans,while on many occasions only thethecae were found. Furthermore,the examination of preserved watersamples collected in 2004 revealedthat G. cf. fragilis was also presentin summer 2004 when mucilagephenomena were also intense. Thehighest abundances of Gonyaulax(7.92x10 3 cells/L) were found onAugust 2005 in integrated watersamples, while their abundance in2004 did not exceed 1.40x10 3cells/L.PO.13-32DSP shellfish toxicity in relationto occurrence of Dinophysis fortiiand D. caudata bloomsSession: PO.13 - Regional eventsŽ Nincevic Gladan, I Marasovic, SSkejic, M BužancicInstitute of Oceanography and Fisheries,SPLIT, CroatiaTemporal and spatial distribution ofDinophysis species in relation toDSP shellfish toxicity was studied atsix areas with 13 sampling stationsalong the eastern Adriatic coastfrom January 2001 to December2005. Seven potentially toxicDinophysis species were recordedincluding D. acuta, D. acuminata, D.caudata, D. fortii, D. rotundata, D.sacculus, and D. tripos. Dinophysisspecies differed in seasonaloccurrence. Dinophysis acuta, D.acuminata and D. sacculus weremore abundant in spring and autum.Dinophysis rotundata and D. triposoccurred in high abundance duringwinter and spring, while higherabundance of D. rotundata in NWAdriatic usually occurred in earlysummer. Dinophysis caudata andD. fortii showed maximumabundance in summer and autumn.Dinophysis species showed strongseasonal variability and differentspatial distribution. Diarrheticshellfish toxins outbreaks wereusually associated with thepresence of D. fortii and D. caudata.Dinophysis fortii was alwaysassociated with shellfish toxicitywhile D. caudata blooms werepresent during both periods withand without shellfish toxicity,indicating D. fortii as the most DSPtoxic species in these areas.PO.06-07The emergence and dynamics ofred tide blooms caused byCochlodinium polykrikoides inthe Peconic Estuary, NY, USASession: PO.06 - Population dynamicsR Nuzzi 1 , CJ Gobler 21 Suffolk County Department of Health Serv,YAPANK, United States of America2 Stony Brook University, SOUTHAMPTON,United States of AmericaThe dinoflagellate Cochlodiniumpolykrikoides is well known forforming harmful red tide blooms inAsian waters to the detriment offisheries and aquaculture there. Inthe US, C. polykrikoides bloomshave been less common. Here wereport on the emergence of a C.polykrikoides blooms in the PeconicEstuary, NY, USA, during the latesummer and early fall of 2004 and2005. During both years, bloomsachieved cell densities exceeding10 7 /L and chlorophyll levelsexceeding 100μg/L throughoutmuch of the estuary, althoughbloom waters were characterized byextreme patchiness. Highresolutionspatial and temporalsampling during 2005 suggested251