Chapter 11 — Species of Special Concern 



suggested that, at that time, pollutants were not a 

 significant threat to the vaquita. 



The greatest known threat to the vaquita appears to 

 be incidental catch in gillnets, especially large-mesh 

 nets used in fisheries for the endangered totoaba 

 (Totoaba macdonaldi), other finfish, sharks, and sea 

 turtles. The totoaba fishery began in the niid-1920s 

 and peaked m the 1940s. By the early 1970s, the 

 totoaba catch had declined so dramatically that the 

 Mexican Government closed the fishery in 1975 to 

 allow the recovery of the stock. Nevertheless, illegal 

 totoaba fishing continues, and vaquita mortality due to 

 incidental take is still high. To assess the status of the 

 totoaba stock, the Mexican Government began autho- 

 rizing experimental gillnet fishing in 1985. Between 

 1985 and 1991, at least 121 vaquitas were reported 

 killed in fishing nets, including at least 52 in the 

 experimental totoaba fishery. Due to under-reporting 

 by fishermen, however, the true number is probably 

 much greater. 



Several protective measures have been taken for 

 both the vaquita and the totoaba. Both are listed 

 under Appendix I of the Convention on International 

 Trade in Endangered Species of Wild Fauna and Flora 

 (CITES) — the totoaba in 1977 and the vaquita in 

 1979. In 1978, the Government of Mexico designated 

 the vaquita as rare and in danger of extinction. That 

 same year, the International Union for the Conserva- 

 tion of Nature and Natural Resources (now called the 

 World Conservation Union) listed the species as 

 vulnerable in its Red Data Book. It is presently listed 

 as endangered. In 1979, the totoaba was listed as 

 endangered under the U.S. Endangered Species Act; 

 following a recommendation by the Marine Mammal 

 Commission, the vaquita received the same designa- 

 tion in 1985. 



In 1988, a study of fishermen's knowledge of and 

 interactions with the vaquita in the northern Gulf of 

 California was conducted by the Center for the Study 

 of Deserts and Oceans in Tucson, Arizona, in coop- 

 eration with the Universidad Nacional Autonoma de 

 Mexico. The study concluded, among other things, 

 that all reported takes occurred in waters less than 160 

 feet deep and estimated the annual fishery-related 

 mortality of vaquita at about 32 animals. The study 

 report recommended: (1) closing certain areas to 



gillnet fishing; (2) explicitly prohibiting all sale of 

 totoaba; and (3) developing (a) economic alternatives 

 for gillnet fishermen, (b) public education programs 

 focusing on conservation of marine resources in the 

 northern Gulf of California, and (c) a management 

 plan for the vaquita. 



Also in 1988, the Cetacean Specialist Group of the 

 World Conservation Union's Species Survival Com- 

 mission published an action plan for conserving the 

 biological diversity of cetaceans throughout the world. 

 The plan proposed, among other things, a three-year 

 project for research and conservation of the vaquita. 

 The Cetacean Specialist Group considered the vaquita 

 project among those deserving the very highest 

 priority. The project would include: (1) a populafion 

 monitoring program, including vessel-based censuses; 



(2) a program to monitor incidental take by fisheries; 



(3) examination of vaquita carcasses; (4) a public 

 awareness program; and (5) a recovery plan for the 

 species. In 1990, the Cetacean Specialist Group, with 

 partial support from the Marine Mammal Commis- 

 sion, established an office at the National Marine 

 Fisheries Service's Southwest Fisheries Science Center 

 in La Jolla, California, to help implement action plans 

 for the vaquita and other species. The office moved 

 in 1991 to Texas A&M University in Galveston. 



In October 1990, the Workshop on the Mortality of 

 Cetaceans in Passive Fishing Nets and Traps was 

 convened at the request of the International Whaling 

 Commission. The Marine Mammal Commission gave 

 partial support to the workshop, which reviewed the 

 worldwide incidental take of cetaceans in fishing gear. 

 Workshop participants noted that the vaquita's future 

 is seriously threatened by illegal totoaba fishing and 

 other gillnet fisheries and that inadequate enforcement 

 and a lack of economic alternatives for gillnet fisher- 

 men were exacerbating the problems. 



On 10-20 May 1991, the IWC's Scientific Com- 

 mittee met in Reykjavik, Iceland. At the meeting, the 

 Scientific Conmiittee endorsed several recommenda- 

 tions concerning the vaquita forwarded by its subcom- 

 mittee on small cetaceans. Affording the vaquita the 

 highest priority of any endangered cetacean species, 

 the full Scientific Committee recommended that action 

 be taken to fully enforce the closure of the totoaba 

 fishery and immediately halt illegal shipments of 



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