OVERVIEW 



The Southeast Fisheries Science Center (SEFC) coordinated a multi-disciplinary 

 investigation into the cause, extent, and potential effects of higher than previously reported 

 numbers of bottlenose dolphin {Tursiops truncams) strandings which occurred during 1990 

 in the northern Gulf of Mexico. The majority of the funding for this investigation was 

 provided by the National Marine Fisheries Service Office of Protected Resources. The 

 investigation of the Gulf strandings was organized into seven main themes. Four of the 

 themes were concerned with population biology and included: 1) stranding rate and trends; 

 2) population abundance and strandings; 3) age structure of stranded animals; and 4) food 

 habits. The other themes related to extent and causes of mortality, and included studies of: 

 5) environmental factors; 6) biotoxins; and 7) contaminants. Summaries of each theme are 

 provided in the overview; the complete reports on each theme are presented as separate 

 sections. The available pathology reports are summarized in Section DC 



The SEFC took several steps to assist the Southeastern U.S. Stranding Network 

 (SEUS) in stranding reporting and recovery operations during the mortality investigation. 

 Communications were established with Network participants throughout the Gulf to 

 ascertain stranding rates, to alert participants to the ongoing event, and to request collection 

 of a standard set of tissue samples. SEFC personnel participated in stranding recovery 

 operations in Texas and Mississippi. Strandings along the Louisiana coast were documented, 

 and occasionally examined, by SEFC personnel onboard routine U.S. Coast Guard helicopter 

 flights. Strandings on the barrier islands of Mississippi were documented by SEFC pei^onnel 

 conducting offshore surveys for marine mammals. Small boat surveys, funded or conducted 

 by the SEFC, were conducted along the Texas and Alabama coasts to visually examine 

 bottlenose dolphin herds for the presence of "affected" animals. Authorization was obtained 

 to collect, hold, and examine afff-f red animals. However, no affected animals were observed 

 during the surveys. 



The Texas Marine Mammal Stranding Network (TMMSN) was provided with 

 equipment and supplies to deal with the large numbers of animals stranding along the Texas 

 coast. Travel expenses were provided to veterinary pathologists and others assisting the 

 TMMSN. The SEFC also provided funds to cover costs for shipping specimens. 



The Beaufort, Charleston, Galveston, Miami and Mississippi Laboratories of the 

 SEFC and the National Marine Fisheries Service Office of Protected Resources provided 

 support for the investigation. Additional support was provided by a variety of agencies, 

 institutions and other groups and individuals, including: the Armed Forces Institute of 

 Pathology; the University of Miami's Cooperative Institute for Marine and Atmospheric 

 Sciences; Environmental Protection Agency; Florida Department of Natural Resources; 

 Greenpeace; Kansas State University; Louisiana University Marine Consortium; Marine 

 Mammal Commission; National Oceanic and Atmospheric Administration Aircraft 

 Operations Center; Oak Ridge National Laboratories; Sea World Orlando; Smithsonian 



