CHAPTER III 



SPECIES OF SPECIAL CONCERN 



The Marine Mammal Commission, in consultation with its 

 Committee of Scientific Advisors on Marine Mammals, reviews the 

 status of marine mammal populations and makes recommendations to 

 the Departments of Commerce and Interior on research and 

 management actions needed to achieve the purposes of the Marine 

 Mammal Protection Act and the Endangered Species Act. During 

 1989, the Commission continued to devote special attention to 

 several species of marine mammals designated as endangered or 

 threatened, including West Indian manatees, Hawaiian monk seals, 

 California sea otters, humpback whales, right whales, bowhead 

 whales, and Gulf of California harbor porpoise. Given the 

 serious conservation issues involving several other marine mammal 

 species or populations, the Commission also focused attention on 

 North Pacific fur seals, Steller sea lions, bottlenose dolphins, 

 Hector's dolphins, and polar bears. A review of the Commission's 

 activities regarding these species and populations follows. 



West Indian Manatee (Trichechus manatus) 



West Indian manatees occur on the east coast of North and 

 South America from the southeastern United States to northern 

 Brazil. They prefer the lower reaches of rivers and protected 

 coastal waters along the mainland coast of the western Atlantic 

 Ocean, the Gulf of Mexico, and the Caribbean Sea. They also 

 occur around the Greater Antilles from Cuba to Puerto Rico. The 

 species is endangered throughout its range. 



The largest known concentration of animals is centered in 

 the rivers and coastal waters of Florida, where at least 1,200 

 animals occur. Remaining populations outside the United States 

 are thought to be small and declining in numbers due to poaching, 

 incidental take in gillnets, loss and degradation of habitat, and 

 other threats. Thus, the long-term survival of a viable 

 population of manatees very well may depend on the success of 

 efforts to protect animals in the southeastern United States. 



Survival of manatees in the United States, however, also is 

 in grave doubt due to: (1) the killing and injuring of 

 increasing numbers of animals by vessels on Florida's waterways; 

 (2) degradation of remaining manatee habitat by intense coastal 

 development; and (3) periodic episodes of high natural mortality. 

 The first two factors are direct outgrowths of rapid human 

 population increases in recent years. 



As indicated on the table on the following page, known 

 manatee mortality has increased in recent years and is continuing 



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