Investigating bottlenose dolphin health along the Florida panhandle, at the site of a series of Unusual Mortality Events
By Lori Schwacke, PhD, NOAA's Center for Marine Animal Health

In July 2006, NOAA's Marine Mammal Health and Stranding Response Program conducted the second year of our dolphin health assessment research project in St. Joseph Bay, Florida with support from partners including the Chicago Zoological Society's Sarasota Dolphin Research Program, Mote Marine Laboratory, NOAA's Ocean Service, Ocean Embassy, University of North Carolina at Wilmington, Florida State University, Florida Fish and Wildlife Conservation Commission, and several public display facilities such as Gulfworld Marine Park, Dolphin Quest, Disney's Living Seas, the Mirage Dolphin Habitat, and Mystic Aquarium. The research is part of an extensive investigation into several bottlenose dolphin Unusual Mortality Events (UMEs) that have occurred in and around St. Joseph Bay along the Florida panhandle since 1999. Many of the mortalities have been linked to brevetoxin exposure, which is caused by red tide blooms.

The first year of the research project began in April of 2005 to evaluate the health of live dolphins in this area, and 12 animals were handled over a two-week period. The primary objective of the research is to determine if there are differences in health parameters between this population and other dolphin populations along the Florida central west coast which could indicate an increased vulnerability to brevetoxicosis for the panhandle dolphins. Nearly half of the dolphins sampled in the St. Joseph Bay area in 2005 showed blood parameters that were significantly elevated as compared to dolphins sampled from other coastal populations, such as Sarasota Bay. During the July 2006 field season, which also lasted two weeks, 18 additional dolphins were sampled, and preliminary results again indicate nearly half of the animals sampled have out-of-range blood parameters. Whether or not the abnormal health parameters are linked to an increased susceptibility to brevetoxicosis is still under investigation. The long-term research conducted by the Sarasota Dolphin Research Program has significantly contributed to our overall understanding of dolphin health and has provided an important baseline to evaluate and assess dolphins in other areas.