The vaquita porpoisePaula Olson / NOAA Fisheries

A species of porpoise only found in the Gulf of California in Mexico may become extinct by 2022 if harmful fishing practices continue, scientists say.

The vaquita, the smallest of the seven species of porpoise, is considered the most endangered marine mammal in the world. Only about 60 vaquita porpoises remain, according to a team of international scientists created by the Mexican government. The porpoises are often caught and drowned in nets set by fisherman for other marine creatures, particularly the totoaba fish. The swim bladders of totoaba, another endangered species, can sell for thousands of dollars in China, where they are used as an ingredient in soup.

“We are watching this precious native species disappear before our eyes,” said Lorenzo Rojas-Bracho, the chair of the International Committee for the Recovery of the Vaquita, last week.

In 2015, Mexican President Enrique Peña Nieto imposed a two-year ban on the use of gillnets— nets hung vertically in water to entangle fish by their gills—in the northern Gulf of California. The Mexican Navy also patrols the area to clear the nets. Conservationists say outlawing gillnets permanently is crucial for the vaquita’s recovery and survival.

Vessel surveys and acoustic monitoring of vaquita sonar clicks shows the mammals’ population has decreased drastically in the last two decades. In 1997, about 567 vaquita swam the waters of the Gulf of California. By 2008, the population had shrunk to 245.

Barbara Taylor, a conservation biologist with NOAA’s Southwest Fisheries Science Center in California, said the Mexican government began to consider seriously the vaquita’s potential extinction in 2006, after the Chinese river dolphin was declared extinct when Taylor and a group of scientists could not find a single dolphin in the Yangtze River. Mexico suddenly became home to the world’s most endangered marine mammal, she said in a NOAA podcast in March.

Taylor said the vaquita population could recover with proper government intervention and enforcement. She cited the success story of the northern elephant seal: in 1922, the Mexican government designated Guadalupe Island as a protected area, allowing the population of less than 100 elephant seals there to grow to tens of thousands.

“Marine mammals show an amazing capacity to recover if you just stop killing them,” Taylor said.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.