Plight of the Vaquita

News from an article published in Mammal Review:

"Research published in the academic journal Mammal Review has uncovered the missing link in the depleting population of the vaquita. With a body less than 1.5 m long, the vaquita is the smallest living cetacean (the order Cetacea consists of whales, dolphins and porpoises). It also has one of the smallest ranges (c. 2235 km2) and one of the smallest populations (Mammal Review, the authors from Mexico and Canada reviewed the scientific issues, described previous and ongoing conservation efforts, and identified remaining obstacles, established priorities, and provided recommendations.
"The vaquita is endemic to the north-western corner of the Gulf of California (north of 30º45'N and mainly west of 114º20'W), an area rich and diverse in marine mammals. It is somewhat surprising that the porpoises are limited to such a small area when there are no obvious physical barriers to prevent them from moving into the rest of the Gulf. However, there is no evidence that the vaquita’s overall range has changed in historic times. Acoustic surveys suggest that vaquitas are not only limited to the north-western Gulf all the year-round, but also that their current distribution is more restricted than previously thought – confined to a small area off the eastern coast of the Baja California Peninsula.
"What is driving the vaquita towards extinction? It is not, as is so often the case, degradation of its habitat. A risk factor analysis discounted pollution or the drastic reduction of freshwater flow from the Colorado River as primary culprits. It is also not a genetic problem. Genetic analyses and population simulations suggested that the vaquita has always been rare and that its extreme loss of genomic variability occurred over evolutionary time rather than recently owing to human-caused mortality. Instead of those factors, the 'smoking gun' in this instance is accidental mortality in fishing gear, something popularly known as 'bycatch.'" ...
"For the first time since 1958, when the vaquita was scientifically described and named as a species, the Mexican Government has finally taken specific actions to try to prevent its extinction. On 29 December 2005 the Ministry of Environment declared a Vaquita Refuge that contains within its borders approximately 80% of all verified vaquita sighting positions. In the same decree, the State Governments of Sonora and Baja California were offered $(US)1 million to compensate affected fishermen. Another big step will be to convince the relevant State Governments of the Upper Gulf to support actions proposed by an international vaquita recovery team. These Governments have argued that no action should be taken until a second survey for a new abundance estimate shows definitively that the population is declining."

[Full news posted to StrangeArk archive.]