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 2006a multi-nutrient predator–prey model, it is demonstrated that these blooms candevelop through the self-propagating failure of normal predator–prey activity,resulting in the transfer of nutrients into HAB growth at the expense of competingalgal species. Rate limitation of this transfer provides a continual level of nutrientstress that results in HAB species exhibiting grazing deterrents protecting them fromtop-down control. This process is self-stabilizing as long as nutrient demand exceedssupply, maintaining the unpalatable status of HABs; such events are most likelyunder eutrophic conditions with skewed nutrient ratios.”Mitra, A. and K.J. Flynn. 2006. Promotion of harmful algal blooms by zooplanktonpredatory activity. Biology Letters.http://www.journals.royalsoc.ac.uk/link.asp?id=pa6a316clj7hhSunda, W.R., E. Granéli and C.J. Gobler. 2006. Positive feedback and thedevelopment and persistence of ecosystem disruptive algal blooms. Journal ofPhycology (on line August athttp://www.blackwellpublishing.com/journal.asp?ref=0022-3646&site=12. Human Health and HABsRoom: will be announcedConvener: Lorraine Backer and Heléne AnnadotterThe first part of the symposium will address, using Florida red tide as an illustration,how marine harmful algal blooms (HABs) can affect coastal communities. In July,2006, the National Oceanic and Atmospheric Administration, the Florida Fish andWildlife Conservation Commission, Mote Marine Laboratory and the State of FloridaInstitute of Oceanongraphy hosted the workshop and public forum “State of theResearch on Red Tide in the Gulf of Mexico.” At the July workshop, speakersreviewed the progress in understanding this phenomenon in the contexts of Kareniabrevis biophysiology, bloom dynamics and ecology, fisheries and food safety,oceanography, human health, economics, and community education and outreach.Red tides appear to be increasing in the frequency and intensity and are an ongoingthreat to Florida’s Gulf coast communities. In this workshop, there will be a briefpresentation summarizing these community impacts that will set the stage fordiscussion about future directions for research on the effects of marine HABs oncoastal communities.The second part of the symposium will deal with the impact of cyanobacterial bloomson public health and the quality of drinking water. In the past decades, a number ofreports of mass developments of cyanobacteria have appeared globally. A largenumber of documented incidents of death among animals, associated withcyanobacterial blooms, exist. Data on exposure of humans to cyanotoxins arelimited. A range of symptoms among humans exposed to cyanobacteria in drinkingwater or in connection with swimming, have been documented. In most of thesecases, the level of cyanotoxins were never measured. In a few cases, microcystinswere measured but found to be around WHO´s safe level. In these cases, healthproblems such as fever, headache, skin rashes, abdominal pain, and muscle painwere reported. But which toxins and/or organisms are the cause of these differentsymptoms? The discussion will focus on the level of, and the role, of differentcyanotoxins and cyanobacteria-associated organisms for the symptoms reported inconnection with exposure of cyanobacteria in drinking water and during recreation.83