health hazard as well as a threat to marine mammals. Therefore, 

 in 1988, the National Marine Fisheries Service initiated a "coast 

 watch" program using weekly satellite data on ocean surface 

 thermal and salinity conditions to monitor red tide blooms 

 reported along the North Carolina coast at that time. In 

 addition, on 8-9 May 1989, the National Marine Fisheries Service 

 and the Woods Hole Oceanographic Institution convened a group of 

 experts at Woods Hole, Massachusetts, to discuss the possible 

 link between natural biotoxins and the recent mass mortalities of 

 bottlenose dolphins and humpback whales along the eastern coast 

 of the United States. The focus of the discussion was on the 

 possible role of dinof lagellate toxins in these events. The 

 objectives of the meeting were to review and assess the existing 

 evidence and to recommend research needs and priorities. 



As regards bottlenose dolphins, the Workshop participants 

 concluded that no single pathological disorder could be 

 identified as common to all dead dolphins. The report of the 

 Workshop noted that a compound eguivalent to, or at least 

 structurally and functionally similar to, the dinoflagellate 

 neurotoxin brevetoxin was found in the livers of some dolphins 

 that died during the 1987 mortality event. Analyses of several 

 specimens of wild-caught menhaden and specimens from dolphin 

 stomachs also contained a brevetoxin-like compound. This 

 supports the hypothesis that brevetoxin-contaminated food fish 

 instigated the mass mortality by suppressing the dolphins' immune 

 systems, thus increasing their susceptibility to secondary 

 microbiological insults. The participants noted that evidence 

 for this scenario was largely circumstantial and that other 

 explanations were possible. 



On the basis of the discussions, the Working Group concluded 

 that implications with respect to marine mammal mortalities, 

 commercial fisheries, and public health were sufficient to 

 justify further investigations into the impact of dinoflagellate 

 toxins on higher trophic levels, and it suggested a series of 

 research and monitoring programs. Specifically, as regards 

 Tursiops populations, the Working Group recommended that tissues 

 be collected from animals stranded on Gulf of Mexico and Atlantic 

 coast beaches or taken incidental to commercial fisheries, that 

 they be analyzed for the presence of brevetoxin, and that funds 

 be allocated for the necessary chemical analyses and assays. 



Proposal for Depleted Designation — Data from population 

 studies done in the late 1970s and early 1980s suggest that there 

 could be two more or less discrete stocks of bottlenose dolphins 

 along the U.S. east coast — a nearshore stock that moves north 

 to the New Jersey/New York Bight area in the spring and south to 

 the Georgia/Florida area in the fall, and an offshore stock that 

 occurs primarily along the 100-fathom depth contour between 

 Georges Bank in the north and Cape Hatteras in the south. Data 

 from animals that died and washed ashore in the summer of 1987 



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