The organization that regulates world trade in plants and animals has asked its member nations to stop buying protected species Mexico exports legally, a move intended to punish the country for failing to safeguard the nearly extinct vaquita porpoise (Phocoena sinus).

On March 27, the secretariat of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (Cites) declared that a plan Mexico had submitted to stop illegal fishing in the vaquita habitat was inadequate. Invoking sanctions, the body recommended that Cites signatory nations suspend commercial trade with Mexico of any species listed under the agreement.

An estimated 10 vaquitas remain in their habitat in the northern reaches of the Gulf of California. The diminutive marine mammals become entangled and drown in gillnets set for a fish which shares the vaquita habitat, the endangered and highly prized totoaba (Totoaba macdonaldi).

Demand in China for the totoaba’s swim bladder, which is considered to have medicinal value, drives illegal fishing in the vaquita refuge, so Mexico’s failure to curb totoaba poaching is considered the prime cause of the vaquita’s plight. Organized crime rings are believed to buy the totoaba from the fishers and control the export of dried totoaba swim bladders to China, where each one fetches thousands of dollars.

Navy patrols

For years the Mexican Navy has been patrolling a 1,841-square-kilometer (711-square-mile) vaquita refuge in the upper Gulf of California where gillnet fishing is prohibited. The refuge includes a smaller 225-square-kilometer (87-square-mile) zone established in 2020 where no fishing of any kind is allowed.

That zero-tolerance area is where the most recent vaquita sightings have occurred during expeditions in September and October 2019 and again in October and November 2021. The elusive porpoises have also been detected by acoustic equipment positioned in that area.

But Navy enforcement is lax and fishing boats equipped with gillnets consistently violate the zero-tolerance zone.

Sea Shepherd Conservation Society, a marine wildlife protection nonprofit that removes nets and monitors illegal fishers, counted 117 fishing skiffs, known as pangas, on one day in November 2021 during the shrimping season.

Although gillnets set to catch totoaba pose the greatest threat to the vaquita because the animals are of similar size, the shrimping gillnets also place the vaquita at risk. Despite years of promises, Mexican fisheries authorities have failed to develop effective alternative fishing techniques for the local fleets in the upper Gulf of California.

There have been a few encouraging signs, including more vigorous enforcement by the Mexican Navy last year, according to a March 9 report by Kristin Nowell of the Cetacean Action Treasury for the International Union for Conservation of Nature (IUCN).

Last summer, the Navy dropped 193 concrete blocks fitted with 3.5-meter tall hooks in a grid pattern across the zero-tolerance zone to snag and disable the gillnets. The hope was that once fishers realized they would lose their nets, they would stay out of the area.

The plan appeared to have effect. The maximum daily count of pangas fell by between 74% to 86% during the peak fishing periods in November and December 2022 compared to the year before.

At the same time, acoustic detection of the vaquitas’ echolocation clicks increased, probably as a result of a change in their behavior in an area with fewer nets, Nowell wrote.

Focus on gillnets

Still, experts warn that for the vaquita to recover, gillnet fishing in the refuge must be completely eliminated. Last November, the Cites secretariat asked Mexico to present a compliance plan outlining the steps it would take to stop illegal fishing in the vaquita habitat. The Mexican government was asked to present a timeframe and a way to assess implementation of each step.

Mexico submitted its plan to the Cites secretariat in February and revised it after receiving suggestions from the organization. But on March 27, Cites pronounced the action plan inadequate and recommended the trade sanctions, which could affect Mexican commerce in a wide variety of flora and fauna. The U.S.-based Center for Biological Diversity says nearly 3,150 Mexican animals and plants are listed by Cites, and many are exported under a licensing system in line with Cites protocols to ensure their conservation. Among the products that will be affected are mahogany, tarantulas, orchids, and leather from captive and wild reptiles.

“We think it absolutely will have an impact,” says D.J. Schubert, a wildlife biologist with the Animal Welfare Institute, a U.S.-based nonprofit. “The vast majority of countries will comply with the recommendation. Mexico has been failing the vaquita for 25 or 30 years. They can’t claim ignorance. They know what to do. They have been told what to do, and they refuse to do it.”