The annual occurrence of Karenia brevis in the Gulk of Mexico is one of the most significant harmful? algal blooms (HABs) in the coastal waters of the United States. This HAB species has a large economic,? health, and environmental impact on Gulf coast communities, especially in Florida, through massive fish? kills, deaths of marine mammals and birds, human consumption of toxin-contaminated seafood, and? respiratory effects from aerosolized toxins. Over the past few decades the incidence of K. brevis blooms? appears to be increasing in both frequency and duration. Current government-mandated programs for? monitoring this HAB species must rely on microscopic cell counts. These counts are time consuming, have? low sample through-put, and require highly-skilled microscopists who are experts at identifying and? enumerating Karenia brevis cells of varying morphologies in complex natural phytoplankton assemblages.? There is consensus among HAB researchers and public health professionals that monitoring efforts for? HABs must evolve towards the use of rapid, accurate, sensitive, and objective molecular-based detection? and quantitation methods.? The proposed project will first utilize a combination of molecular techniques, such as Fluorescent In Situ? Hybridization (FISH) and real-time quantitative polymerase chain reaction (qPCR), with traditional methods? (light and fluorescent microscopy) to enumerate Karenia brevis cells in laboratory cultures. The objective of? this initial phase is to test the efficacy of, and where feasible optimize, molecular methodologies with a? short (3-5 hour) processing time for use in natural populations. Second, we will apply a combination of? metabolic measurements (cell division, photosynthesis and respiration rates) and flow cytometry? methodologies in cultures, and then natural popualtiosn, to improve our understanding of how? environmental factors influence the metabolic state of K. brevis. Third, we will attempt to relate these? indices to environmental parameters. The ultimate objective of this research is to facilitate the idenitfication? and enumeration of this HAB species, and develop near real-time indices to assess the metabolic state of? Karenia brevis in various stages of bloom development.? Significance: It is anticipated that the results of this project will enhance our understanding of what? factors contribute to Karenia bloom development. It will also synergistically enhance other collaborative? HAB research programs through a rapid-response sampling program and sharing of samples and data.
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