designated the Gulf of California harbor porpoise as endangered 

 under the Endangered Species Act. In 1988, researchers from 

 the Center for the Study of Deserts and Oceans and the 

 Universidad Nacional Autonoma de Mexico began a cooperative 

 program, funded by the Center for Environmental Education 

 (now the Center for Marine Conservation) , to interview fishermen 

 in the northern Gulf of California. The objectives are to 

 obtain better information on incidental porpoise mortality 

 and to advise fishermen and others of the rare and endangered 

 status of the species. If successful, this effort should 

 provide more reliable information on when, where, how, and 

 how many Gulf of California harbor porpoise are being caught 

 and killed in gill net fisheries. It also may suggest ways 

 to avoid or reduce the incidental take. 



River Dolphins (Superfamily Platanistoidea) 



The Platanistoidea superfamily of toothed whales is 

 composed of five species commonly known as river dolphins. 

 It includes the only cetaceans whose natural habitat is limited 

 to fresh-water environments. The species and their distribution 

 are: Platanista gangetica , known as the Ganges or blind 

 river dolphin, found in India, Bangladesh, and Nepal; P. 

 minor , the Indus river dolphin, found in the Indus River 

 system of Pakistan; Inia geof frensis , the boto or Amazon 

 river dolphin, found in the Amazon and Orinoco River basins 

 in South America; Lipotes vexillifer , the baiji or Chinese river 

 dolphin, presently found along the middle and lower Yangtze 

 River in the Peoples Republic of China; and Pontoporia 

 blainvillei , the franciscana or the La Plata river dolphin, 

 found in the South Atlantic coastal waters off Argentina, 

 Uruguay, and Brazil. Pontoporia is the only member of the 

 group that inhabits salt water. 



Although little is known about the population status and 

 ecology of river dolphins, there is reason to believe that 

 all five species may be threatened to varying degrees with 

 extinction due to subsistence hunting, incidental take by 

 fisheries, and/or human-caused destruction and degradation of 

 habitat. Construction of dams and other development in and 

 near important river dolphin habitat pose potentially serious 

 threats to the continued survival of several of the species. 

 The baiji, Ganges river dolphin, and Indus river dolphin are 

 listed on Appendix I of the Convention on International Trade 

 in Endangered Species of Fauna and Flora, and the boto and 

 franciscana are listed on Appendix II. 



On 23 December 1986, the Commission wrote to the National 

 Marine Fisheries Service recommending, among other things, 

 that steps be taken to list the five species of river dolphins 

 as threatened or endangered under the U.S. Endangered Species 



71 



