The world’s most endangered marine mammal, a small porpoise called the vaquita, is hanging onto existence and appears to be benefiting from new conservation measures, according to the results of a new scientific survey of the species that was made public on Wednesday.
An international team of scientists estimated that at least 10 vaquitas remain in the Gulf of California, the waters that separate Baja California from the Mexican mainland. The porpoises are found nowhere else and have been driven to the brink of extinction by drowning in gill nets, a type of fishing gear that drifts like a huge mesh curtain, catching fish by their gills. Dolphins, sea turtles and vaquitas get stuck, too, dying when they can’t surface to breathe.
Researchers used visual identification and acoustic monitoring over 17 days in May to survey the population. Among the video footage captured of the elusive animals was a little dorsal fin surfacing alongside a larger one, evidence of a calf swimming next to its mother.
The estimated number of vaquitas in the new survey was similar to the previous one, conducted in 2021. Back then, researchers were aghast by what else they saw: More than 100 fishing boats in a highly protected zone known as the zero-tolerance area. At the time, the Mexican Navy acknowledged its lack of enforcement to The Times.
Since then, the navy has started working more closely with the Sea Shepherd Conservation Society, a nonprofit organization that patrols the region looking for gill nets. And last year, the navy took a major new step, dropping a grid of 193 concrete blocks with protruding hooks, designed to entangle gill nets, in the zero-tolerance area. Gillnetting there appears to have dropped by more than 90 percent, the new report notes.
“It’s the biggest conservation success for vaquita that I’ve seen in 30 years,” said Barbara Taylor, a biologist and vaquita expert who led the survey and who recently retired from National Oceanic and Atmospheric Administration Fisheries.
But more will be needed to save the species, she said. While no gillnetting was observed within the zero-tolerance area during the survey, it was regularly seen just northwest, where vaquitas were also spotted. Officially, the gear is banned in a wider zone beyond the zero-tolerance area.
The report recommends expanding the use of the concrete blocks.
“That’s such easy, low-hanging fruit for the Mexican government,” Dr. Taylor said. “They know where to do it, they know where to go, they know it will make a difference right away, before the next fishing season.”
A harder step is transitioning local economies that rely on gill nets to new gear. One large and endangered fish in the region, the totoaba, has made the situation particularly volatile because its swim bladder commands high prices in Asia, attracting illegal trafficking and organized crime. But legal species are fished with gill nets, too, including shrimp, corvina and mackerel.
One local effort to promote vaquita-safe equipment is run by a group called Pesca ABC. Its methods yield a higher-quality catch, but so far there’s only enough demand from seafood buyers to support about 30 fishers.
Katy Carpio works with Pesca ABC and was one of a few community members who participated in the survey, receiving training on how to identify the animals. Out with the researchers, she saw a vaquita for the first time.
“It was a lot of emotion,” she said. “A lot of happiness, adrenaline.”
The animals are so rare and hard to spot that many in the community don’t believe they exist. “They tell me, ‘It was a dolphin, it was this, it was that,’” Ms. Carpio said. “And I tell them, ‘Wait until they release the results, then you’ll see the pictures.”
What’s key for the future, she said, is finding solutions that work for both vaquitas and fishers.
Mexico has come under increasing international pressure to enforce gill net fishing bans throughout protected vaquita habitat. The country faces current or possible trade sanctions under two United States laws, a global treaty on wildlife trade and the United States-Mexico-Canada Agreement.
Preserving the species by bringing some number into captivity isn’t an option. An effort to do just that in 2017 was abandoned after one animal became so stressed by human contact that she died.
“A lot of very experienced people thought that the vaquita would be gone by now,” said Kristin Nowell, executive director at Cetacean Action Treasury, a nonprofit organization dedicated to saving the vaquita from extinction. “The fact that it’s doing better than expected gives Mexico one more chance to get this right.”