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 2006demonstrates that a goodunderstanding of the physicalprocesses which give rise to HABscan lead to robust, but simple,prediction models.O.21-01Wind patterns and HABs inupwelling systemsSession: O.21 - Ecology & Oceanography 2Presentation time: 14:55 - 15:15GC Pitcher 1 , A Fawcett 2 , S Bernard 2 ,AD Cembella 3 , RM Kudela 41 Marine and Coastal Management, CAPETOWN, South Africa2 University of Cape Town, CAPE TOWN,South Africa3 Alfred Wegener Institute,BREMERHAVEN, Germany4 University of California Santa Cruz,SANTA CRUZ, United States of AmericaThe southern Namaqua shelf of theBenguela upwelling system isfrequently subjected to a variety ofHarmful Algal Bloom (HAB)phenomena. Here winds dictatemost physical processes importantto the development of HABs. Thispresentation compares two periodsof study (15 March – 16 April 2005and 7 – 23 March 2006), followingclearly different wind patterns. The2005 study was dominated bydinoflagellates including species ofDinophysis and Protoceratiumreticulatum, responsible for theproduction of DSP toxins andyessotoxins, respectively, while the2006 study was dominated byseveral species of Pseudo-nitzschiaknown to produce domoic acid. Thewind patterns leading to these verydifferent bloom events areexamined in terms of speciesselection and population dynamics.In particular the influence of thewind on the dynamics of the surfacemixed layer, and on local upwellingprocesses determining across-shelfand alongshore flow, and frontaldynamics are investigated.O.21-02The multi-species nature of the2005 Karenia bloom: implicationsfor management and monitoringin FloridaSession: O.21 - Ecology & Oceanography 2Presentation time: 15:15 - 15:35CA Heil 1 , E Truby 2 , J Wolny 3 , R Pigg 2 ,B Richardson 2 , M Garrett 2 , AHaywood 3 , K Petrik 2 , L Flewelling 2 , SCook 3 , E Stone 2 , KA Steidinger 3 , JLandsberg 21 Florida Fish & Wildlife Conservation C C,ST. PETERSBURG, FLORIDA, UnitedStates of America2 Florida Fish & Wildlife Cons. Commission,ST. PETERSBURG, FL 33701, UnitedStates of America3 Florida Institute of Oceanography, USF,ST. PETERSBURG, FL 33701, UnitedStates of AmericaThe severe 2005 Karenia brevisbloom was the first Gulf of Mexico-Karenia bloom in which multipleKarenia species were identified andmonitored routinely. Five specieswere present over the course of thebloom: K. brevis, K. mikimotoi, K.papilionacea, K. selliformis and arecognized, but currently unnamedfifth species, Karenia sp. Kareniabrevis was geographicallywidespread and numericallydominant over the entire bloom.Although K. mikimotoi, the secondmost common species, displayedsimilar geographical andtemperature and salinity ranges asK. brevis, it was not present insignificant concentrations until 4months after bloom initiation.Karenia selliformis, alsogeographically widespread, waspresent only during the final bloomstages. Conversely, K.papilionacea was abundant onlyduring the first two bloom months,79