Millions of dollars and two decades of conservation efforts have failed to protect the Gulf of California’s critically endangered vaquita porpoise (Phocoena sinus). Two years ago this species’s population was estimated at 200. Today it has plummeted to just 97. Fewer than 25 of those that remain are thought to be females capable of reproducing and carrying on the species, according to a report (pdf) released this week by the Mexican government's vaquita conservation committee.

Vaquitas, the world's smallest porpoises, have been at the center of a battle between conservationists and local fisherman for years. The animals frequently die when they get caught up in gillnets, which are dragged behind boats to catch shrimp and other commercially valuable species. Mexico banned the use of gillnets in the Vaquita Refuge in 2008 but their illegal use has persisted. In fact, it's gotten worse in recent years because of increasing Chinese demand for the swim bladders of another rare species, a fish called totoaba (Totoaba macdonaldi). Totoaba themselves were listed as critically endangered in 1996, and their sale is banned under the Convention on International Trade in Endangered Species (CITES), but that hasn't helped either species. According to the report "thousands of swim bladders are dried and smuggled out of Mexico, often through the United States... Fishermen receive up to $8,500 for each kilogram of totoaba swim bladder, equivalent to half a year's income from legal fishing activities."

As a result of the vaquita’s decline and the new threat of totoaba fishing, the vaquita conservation committee now warns that the porpoises "will be extinct, possibly by 2018." They are calling on the Mexican government to ban all gillnet fishing not just in the official Vaquita Refuge but also around it, because the porpoises have been known to leave their protected marine territory. They are also calling for greater enforcement of existing laws and more efforts to encourage non-gillnet fishing in the region.

Whether these recommendations are accepted, or if they will even work, remains to be seen. As I wrote back in 2009, local fishermen have long said they would prefer to see the vaquita wiped out. Paying them not to fish hasn't worked: Many of the funds they were given to stop gillnet fishing instead went to buy new boats and motors. If the people of the region don't see value in the vaquita, then the species’s extinction is almost guaranteed.

Photo: Paula Olson/NOAA