The vaquita prefers shallow, turbid, and highly productive waters. Because the vaquita is extremely shy and its population size is so low, little is known about its life history. Most of the research on the vaquita’s range comes from beach strandings, incidental capture in gillnets, and occasional sightings of live animals. It is difficult to survey, due to its small size, inconspicuous surfacing behaviour, and relatively long dive times, especially in the turbid waters where they usually occur. The vaquita does not ride bow waves or perform aerial displays. Sexual maturity likely occurs between three and six years of age, with one calf born every two years. The vaquita’s relatively low fecundity is another reason for grave concern about its ability to sustain the mortality from entanglement in fishing nets. Births usually occur in spring, and the nursing period is thought to be 6 to 8 months long.
The vaquita is only found in the upper Gulf of California (Sea of Cortez). Because the vaquita was first described in 1958 from three skulls found on beaches near San Felipe, Baja California, historical data on this species are sparse to non-existent.
There is a strong, widespread scientific consensus that the primary and most immediate threat to the vaquita is mortality in fishing nets. The vaquita is listed as critically endangered by IUCN-World Conservation Union. A recently published analysis estimates that there are about 150 vaquitas left. Saving the vaquita does not require more scientific knowledge. Rather, measures to eliminate mortality of vaquitas in entangling nets must be implemented immediately. Once such mortality has been eliminated, a recovery program for the vaquita will require realistic socioeconomic alternatives for those who make their living from fishing in the Upper Gulf of California, the availability and use of alternative fishing gear that does not cause vaquita bycatch, and continued enforcement to ensure that there are no entangling nets in vaquita habitat.