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 2006Gymnodinium catenatum. In 2004were also registered the occurrenceof Gambierdiscus toxicus. Duringthis last years, in August, wereobserved the highest peak ofdensities of these species namely265463 cells/L of Pirodiniumbahamense var compressum,164305 cells/L of Gambierdiscustoxicus and 158333 cell/L ofGymnodinium catenatum. Theoccurrence of these species may berelated to the environmentalparameters such as temperatureand salinity.PO.10-13Biology and seasonal distributionof Hermesinum adriaticum in theNew River of North CarolinaSession: PO.10 - Ecophysiology &autecologyR. N. Reger 1 , C. R. Tomas 21 UNCW, WILMINGTON, United States ofAmerica2 University of North Carolina Wilmington,WILMINGTON, NC, United States ofAmericaThe New River in southeasternNorth Carolina is a brackish watersystem having a variety ofmicroalgae that annually formblooms. Some bloom species areconsidered toxic; however one raremicroorganism that may play asignificant role in the river’s ecologyhas been overlooked. An ebridian,Hermesinum adriaticum is foundfrequently in the New River duringmonths when water temperaturesare above ~22 °C. This unicellularorganism contains an internalskeleton protruding from both endsof the cell making the cell about50µm by 20µm. Cell populations inthe New River commonly reach40,000 cells/L and once apopulation of 150,000 cells/L wasobserved at French Creek. Lugolspreserved monthly water samplesfrom seven different stations in theNew River collected from 2001-2006 were observed to determineannual abundance and seasonaldistribution of H. adriaticum. Fromlive samples and cells cultivated inthe laboratory, observations weremade on live material to determinegrowth characteristics, including lifecycle stages, feeding and growthbehavior. Also, detailed studieswere conducted using bothscanning and transmission electronmicroscopy. SEM was used toexamine external morphologicalchanges including possible loss ofskeletons, while TEM was used tostudy nutrition, possibleendosymbiotic relationships, andinternal structural changes.PO.13-38Diarrhetic shellfish toxins at theSwedish West Coast 1987-2005Session: PO.13 - Regional eventsA.-S. Rehnstam-Holm 1 , B Karlson 2 , L.-O. Loo 31 Kristianstad University, KRISTIANSTAD,Sweden2 SMHI, GÖTEBORG, Sweden3 Göteborg University, GÖTEBORG,SwedenDiarrheic shellfish toxins haveoccurred and been regularlychemical monitored in blue mussels(Mytilus edulis) at the Swedish westcoast from year 1987. In generalthere is a seasonal variation ofDSTs in mussels withconcentrations low from March toAugust and high from October toDecember. Peaks above the limitfor consumption have in some yearsalso occurred in late June to lateJuly. A rapid intoxication vs. slowdetoxification of mussels iscommon. Temporal and regionaldifferences are large. Mussels268