Interim Report on the Bottlenose Dolphin (Tursiops truncatus): Unusual Mortality Event Along the Panhandle of Florida, March-April 2004

摘要

This interim report outlines the initial findings and the ongoing analyses in the investigation of the bottlenose dolphin (Tursiops truncatus) mortality event that began in March 2004. One hundred and seven (107) bottlenose dolphins stranded dead along the Florida Panhandle between March 10 and April 13, 2004. Hundreds of dead fish and marine invertebrates were also discovered in the area. The National Marine Fisheries Service formally declared the dolphin deaths an Unusual Mortality Event (UME) after consulting with the Working Group on Marine Mammal Unusual Mortality Events. A multi-agency investigation was initiated and is being conducted by federal and state marine wildlife officials working in partnership with private research organizations and universities. Analyses conducted to date found brevetoxins naturally occurring neurotoxins produced by Karenia brevis, the Florida red tide, at high levels in the stomach contents of all dolphins examined to date and at variable levels in the tissues of these animals. Metabolite concentrations in tissues of fish or dolphins are not yet completed. The concentrations of brevetoxins observed in the analyzed subsample of the stomach contents are greater than or equal to those observed in previous marine mammal mortality events associated with Florida red tides (Karenia brevis blooms) in the Gulf of Mexico.