Florida Panhandle dolphin die-off appears over, investigation continues
The Miami Herald
12th April 2004
A die-off that claimed 105 bottlenose dolphins in the Florida Panhandle apparently has ended, but an investigation of the cause will continue, officials said Monday.
Ron Hardy, co-owner of Gulf World Marine Park at Panama City Beach, said he recommended that the team investigating the deaths declare it over. He expected the team to make a decision within a few days.
"We haven't had any new animals die now in over a week," said Hardy, the team's on-scene coordinator. "Red tide is still the No. 1 suspect.” Red tide is an algae bloom that kills sea life.
The die-off began March 10 and the last death was reported April 3. Most of the carcasses were found in and along St. Joseph's Bay and nearby waters of the Gulf of Mexico surrounding Cape San Blas. A few, however, turned up as far west as Panama City Beach, about 50 miles from here.
Scientists have found a high level of brevetoxin, a powerful neurotoxin released by red tide, in the marine mammals' stomach contents, urine and faeces, but internal lesions usually associated with the poison have been absent.
"We still have a lot of unanswered questions," said Blair Mase, Southeast stranding coordinator for the National Marine Fisheries Service. "Even though the event is over, the investigation will go on for several months."
Mase agreed that red tide is the chief suspect, but she said scientists also would try to determine if another naturally occurring toxin, domoic acid, common to California waters but rare in the gulf, played any part. The substance also was found in the carcasses.
Two young dolphins died at Gulf World during the same period and another pair became ill but are recovering, Hardy said. He said test results are still pending, but he doubted his dolphins were affected by the same thing that killed the wild animals.