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Waters LG, Wolcott TG, Kamykowski D, Sinclair G
Deep-water seed populations for red tide blooms in the Gulf of Mexico
The rapid appearance of a red tide bloom in surface waters of the Gulf of Mexico (GOM) cannot always be linked to a specific sequence of environmental events, indicating that these blooms have more than one potential origin. Waters and co-workers suggest some blooms forming under upwelling conditions along the West Florida Shelf may be seeded by Karenia brevis populations that were behaviorally trapped near the benthos by limited nutrients and light. In a biophysical model, simulated K. brevis exposed to a near-benthic nutrient layer exhibited benthically-oriented diel migration. Vertically migrating Lagrangian drifters demonstrated that natural light could sustain such a population, while near-benthic nitrate/nitrite levels measured at a site in the GOM exceeded those necessary for minimum population growth.