Monitoring the 2007 Florida east coast Karenia brevis (Dinophyceae) red tide and neurotoxic shellfish poisoning (NSP) event

In September 2007, reports of respiratory irritation and fish kills were received by the Florida Fish and Wildlife Conservation Commission (FWC) from the Jacksonville, Florida area.Water samples collected in this area indicated a bloom of Karenia brevis, the dinoflagellate that produces brevetoxin, which can cause neurotoxic shellfish poisoning.For the next four months, K. brevis was found along approximately 400 km of coastal and Intracoastal waterways from Jacksonville to Jupiter Inlet.This event represents the longest and most extensive red tide the east coast of Florida has experienced and the first time Karenia species other than K. brevis have been reported in this area.This extensive red tide influenced commercial and recreational shellfish harvesting activities along Florida's east coast.Fourteen shellfish harvesting areas (SHAs) were monitored weekly during this event and 10 SHAs were closed for an average of 53 days due to this red tide.The length of SHA closure was dependent on the shellfish species present.Interagency cooperation in monitoring this K. brevis bloom was successful in mitigating any human health impacts.Kernel density estimation was used to create geographic extent maps to help extrapolate discreet sample data points into 5 km 2 radius values for better visualization of the bloom.