Estimated extinction time: near future.
 Extract from Reeves et al. (2003, pp. 49): "The Vaquita is endemic to the upper Gulf of California, Mexico (Vidal et al. 1999). Its total abundance is estimated to be in the mid-hundreds (Jaramillo-Legorreta et al. 1999), and the population may be declining rapidly (Barlow et al. 1997). Commercial and artisanal fishing for a variety of species (e.g., sciaenids, scombrids, shrimp, and elasmobranchs) is intensive in the upper Gulf, and the incidental killing of Vaquitas, particularly in gill and trawl nets, is the principal threat (Vidal 1995; D’Agrosa et al. 1995, 2000; Rojas-Bracho and Taylor 1999). In addition, this Critically Endangered porpoise’s habitat has been drastically altered by damming of the Colorado River in the United States. Long-term changes due to the reduced freshwater input are matters of concern and should be investigated. However, the immediate priority is for decisive action to eliminate the bycatch of Vaquitas in fishing gear."
 Barlow, J., Gerrodette, T. and Silber, G. 1997. First estimates of Vaquita abundance. Marine Mammal Science 13: 44–58.
D’Agrosa, C., Lennert-Cody, C.E. and Vidal, O. 2000. Vaquita bycatch in Mexico’s artisanal gillnet fisheries: driving a small population to extinction. Conservation Biology 14: 1110–1119.
D’Agrosa, C., Vidal, O. and Graham, W.C. 1995. Mortality of the Vaquita (Phocoena sinus) in gillnet fisheries during 1993–94. Report of the International Whaling Commission (Special Issue) 16: 283–291.
Jaramillo-Legorreta, A.M., Rojas-Bracho, L. and Gerrodette, T. 1999. A new abundance estimate for Vaquitas: first step for recovery. Marine Mammal Science 15: 957–973.
Reeves, R.R., Smith, B.D., Crespo, E.A. and di Sciara, G.N. (compilers) 2003. Dolphins, Whales and Porpoises: 2002-2010 Conservation Action Plan for the World's Cetaceans. IUCN/SSC Cetacean Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK.
Rojas-Bracho, L. and Taylor, B.L. 1999. Risk factors affecting the Vaquita (Phocoena sinus). Marine Mammal Science 15: 974–989.
Vidal, O. 1995. Population biology and incidental mortality of the Vaquita, Phocoena sinus. Report of the International Whaling Commission (Special Issue) 16: 247–272.
Vidal, O., Brownell, R.L. Jr. and Findley, L.T. 1999. Vaquita Phocoena sinus Norris and McFarland, 1958. In: S.H. Ridgway and R. Harrison (eds) Handbook of Marine Mammals. Volume 6: The Second Book of Dolphins and the Porpoises, pp. 357–378. Academic Press, San Diego, California.
|
