Vaquitas and gillnets: Mexico’s ultimate cetacean conservation challenge

Abstract

There is a high risk that incidental mortality (bycatch) in gillnets will lead to extinction of the vaquita Phocoena sinus, a small porpoise endemic to Mexico’s northern Gulf of California. A zoned Biosphere Reserve established in 1993 proved ineffective at slowing the population’s decline, and in 2005, a Vaquita Refuge was declared. The Refuge Program included a ban on gillnetting and trawling in certain areas with relatively high densities of vaquitas. However, it was not until 2008, with the introduction of a Species Conservation Action Plan for Vaquita (PACE-Vaquita), that a comprehensive protection and recovery effort was introduced. Unfortunately, valuable time was lost as officials first needed to bring order to a poorly managed fishery management system. Also, the voluntary nature of fisherman participation and the chronic deficiency of enforcement have limited PACE’s effectiveness. Although efforts to implement the plan probably slowed the vaquita’s decline, the goal of eliminating gillnets (and thus most vaquita bycatch) by 2012 was not reached. This example shows the difficulty of achieving conservation when the program’s rationale centers on the preservation of biodiversity with less emphasis on meeting community aspirations. In fact, not only does the vaquita have no economic value, but the measures taken for its conservation have a negative economic impact and hence are met with hostility, or at best indifference, on the part of fishery authorities and fishing communities. On a more positive note, a light trawl has been field-tested and shown to be efficient at capturing shrimp; such ‘vaquita-safe’ trawls are suitable for replacing gillnets in the shrimp fishery. Similarly suitable alternative gear needs to be developed urgently for use in the finfish fisheries. Unless entangling nets are removed quickly from the vaquita’s habitat, it will soon be too late to save the species, which probably already numbers fewer than 200 animals.