Vaquita: World's rarest marine mammal captured on video after extinction fears

Sea Shepherd has released the results of its 2024 vaquita survey. And there are worrying signs for the world's most endangered marine mammal.

Footage shows a vaquita fin during the 2024 survey. Source: Sea Shepherd Conservation Society
Footage shows a vaquita fin during the 2024 survey. Source: Sea Shepherd Conservation Society

Vaquita, the world’s rarest marine mammal, has survived another year. The population remains "stable" according to monitoring crews, but the 2024 number is the lowest result ever recorded.

During the last count in 2023, expert spotters supported by Sea Shepherd estimated between 10 and 13 of the tiny porpoises remained. This year just six to eight were sighted during a two-week survey.

Among the individuals filmed with a drone were a mother and her year-old baby. But worryingly no new-born calves were seen.

The critically endangered vaquitas have evolved to survive in a small 300 square kilometre refuge in the Gulf of California, Mexico. DNA testing suggests they were never numerous, and at the turn of the last century it’s estimated there were 500 individuals.

Numbers of vaquita have plummeted over the last 25 years due to illegal gillnet fishing controlled by Mexico’s cartels. The nets target a threatened fish called totoaba whose body parts are traded as a commodity in China. But over the last 25 years fishermen have also inadvertently snared vaquita, pushing the species to the edge of extinction.

In 2021, Yahoo revealed the vaquita was not yet extinct and it was later confirmed between five and 13 vaquitas survived. Two years earlier between seven to 15 individuals were observed.

Despite efforts being ramped up to protect a portion of the vaquita's known territory, known as the Zero Tolerance Area, and remove gillnets, some conservationists remain critical of Mexican government's efforts to protect the species,

Every year international experts join Mexican officials to report on whether the vaquita has survived another year. This year Sea Shepherd praised the work being done to protect the vaquita and vowed to continue the fight.

"We must do everything possible to save the vaquita," Pritam Singh told media on Tuesday (local time) as the results of the May 5 and May 26 survey were released.

Two vaquita seen above the water in the Gulf of California.
A still shows two vaquita documented during a previous survey. Source: Tom Jefferson

The 2024 mission, dubbed Operation Milagro, used two ships supplied by Sea Shepherd, which were supported by Natural Protected Areas Commission of Mexico (CONANP) and the Mexican navy.

Both acoustic and visual monitoring were used to detect the animals and create an estimate of the minimum number of individuals that survive.

Barbara Taylor, the veteran vaquita researcher who led the survey, said the species had been declining at 45 per cent a year, but a handful of individuals have continued to defy expectations and survive.

Previous surveys have documented some with nicks and scars from gill nets, leading to a theory some may have learned to avoid being killed by them. None of these individuals were spotted in 2024.

Despite the survey results being low this year, the team has not conceded the population has dropped, because individuals could have moved from their normal distribution area. Further acoustic monitoring efforts are set to take place between June and December in waters not yet surveyed.

Responding to the survey, Alex Olivera from non-profit Center for Biological Diversity told Yahoo News the vaquita's ongoing survival remains in "grave doubt".

"It's good news that fishing gear entanglement hasn't completely wiped out these little porpoises," he said before adding that "stronger" conservation measures are needed.

"Vaquitas still face a threat of extinction from dangerous gillnets in their habitat and the Mexican government's lax enforcement of protective regulations," he said from Mexico.

"It is crucial that President-elect [Claudia Sheinbaum] commits to enforcing these regulations now to save the vaquita."

DJ Schubert, a senior wildlife biologist at the Animal Welfare Institute agreed that more must be done, and said the gillnets that kill vaquita are still widely used in Mexico despite them now being banned.

"While we commend all involved in conducting the survey, the likely decline in vaquita numbers should be setting off alarm bells in Mexico and around the world," he said.

"Given Mexico’s ongoing failures to stop illegal fishing and the trafficking of totoaba, the government remains complacent in the vaquita’s near-extinction."

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