MARINE MAMMAL COMMISSION - Annual Report for 1998 



• indications in at least one local area — Sarasota 

 Bay — that contaminants may be causing immu- 

 nosuppression and affecting the life span of 

 dolphins; 



• first-born calves survive poorly, possibly because 

 of accumulation of fat-soluble contaminants in the 

 blubber of pre-reproductive females and their 

 transfer in milk during nursing; 



• high levels of persistent organic contaminants 

 were found in the tissues of many of the dolphins 

 that died during the unusual mortality events 

 along both the mid-Atlantic and Gulf coasts; and 



• apparently large, but still undocumented, numbers 

 of bottlenose dolphins are being killed incidental- 

 ly in commercial and recreational fisheries along 

 the mid-Atlantic and Gulf coasts. 



These and other factors were considered during a 

 December 1996 review of the marine mammal re- 

 search program at the Southeast Fisheries Science 

 Center in Miami, Florida. This Center is responsible 

 for providing the information needed by the National 

 Marine Fisheries Service to conserve bottlenose 

 dolphin populations in the coastal waters of the mid- 

 Atlantic and Gulf states. During the program review, 

 the participants were advised that the Service's region- 

 al office in St. Petersburg, Florida, had drafted a 

 bottlenose dolphin conservation plan but, because of 

 other more pressing issues, it did not expect to 

 complete the plan in the foreseeable ftiture. The 

 reviewers identified a broad range of actions that 

 should be included in the conservation plan. 



Representatives of the Marine Mammal Commis- 

 sion participated in the 1996 review. On 31 Decem- 

 ber 1996 the Commission forwarded to the National 

 Marine Fisheries Service its recommendations for 

 staffing and improving the marine mammal research 

 program at the Southeast Center. The Commission 

 also provided an outline illustrating how the various 

 actions identified by the reviewers could be incorpo- 

 rated into a conservation plan. Many of the actions 

 recommended by the reviewers and the Commission 

 subsequently were undertaken. 



During the Marine Mammal Commission's annual 

 meeting in Portland, Maine, on 10-12 November 

 1998, representatives of the Service presented infor- 

 mation on ongoing efforts to determine the discrete- 



ness, size, and productivity of bottlenose dolphin 

 populations in the coastal waters of the mid-Atlantic 

 and Gulf states, and the threats to them. The infor- 

 mation indicated that, although funding has been 

 limited, programs have been initiated to delineate 

 stock structure and to document sources and levels of 

 human-caused mortality and injury, particularly along 

 the Atlantic coast. With regard to the latter point, it 

 was noted that more than 200 bottlenose dolphin 

 deaths in the southeastern United States in the past 

 year were linked to human activities, mostly entangle- 

 ment in fishing gear. The Commission was advised 

 that the Service had contracted with three scientists 

 familiar with bottlenose dolphins and related conserva- 

 tion issues to prepare a conservation plan for bottle- 

 nose dolphins in the northern Gulf of Mexico and 

 along the eastern coast of the United States. 



On 18 December 1998 the Commission wrote to 

 commend the Service for the actions it had taken. 

 The Commission noted that it continued to believe that 

 a conservation plan is needed and that the individuals 

 retained by the Service to draft the plan are well 

 qualified to do so. The letter suggested that the 

 outline developed by the Commission following the 

 December 1996 program review might be useftil in 

 this regard. The Commission also noted that much 

 potentially useful research was being done by volun- 

 teer organizations, students, and non-government 

 researchers. Because of the limited funding available 

 to the Service, the Commission recommended that the 

 conservation plan indicate how volunteers, students, 

 and non-government researchers could be used to help 

 meet the program objectives. 



The Commission pointed out that available infor- 

 mation suggests that there may be at least four reason- 

 ably discrete types of bottlenose dolphin populations 

 in U.S. Gulf and Atlantic waters: (1) a nearshore east 

 coast population that migrates annually between 

 summering areas north of Cape Hatteras, North 

 Carolina, and wintering areas off Georgia and north- 

 ern Florida; (2) year-round resident populations in 

 places such as Sarasota Bay and surrounding areas; 

 (3) populations that occur in deep waters off both the 

 Atlantic and Gulf states; and (4) intermixing resident 

 and migratory populations that overlap seasonally in 

 places such as the Indian and Banana Rivers in east- 

 central Florida. In this regard, the Commission noted 



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