Conservationists are embarking on an all or nothing attempt to save the world’s most endangered marine mammal, the vaquita porpoise.
There are only 30 left in the Gulf of California, the only place where vaquitas are found.
The $4m rescue plan will involve conservationists patrolling the gulf with the help of dolphins trained by the US navy to pinpoint them. The idea is to capture the animals and transport them to a sanctuary in San Felipe, Mexico.
This is truly an all or nothing attempt with considerable risks. No one has ever tried to capture or care for a vaquita before and scientists do not know how they will react. “Some porpoises, like the harbour porpoise, don’t seem to mind too much when captured, but others, such as the Dall’s porpoise, go into shock,” said Barbara Taylor, of the US National Oceanic and Atmospheric Administration. “We don’t know which it is going to be. It is a nerve-racking prospect.”
A spokesman for the International Committee for the Recovery of the Vaquita said, “ultimately, we would like to begin a captive breeding programme with the aim of restoring numbers and finally returning vaquitas to the wild, although we obviously cannot do that until we have dealt with the problems that are causing them to be wiped out at present.”
Twenty years ago, there were about 600 in the region. However, the population has since crashed as a result of illegal fishing of a species called the totoaba. Flesh from its bladder can fetch prices of more than $100,000 a kilo in China, where it is prized for its medicinal properties. “Quite simply, it commands a higher price than cocaine,” said Rojas-Bracho.
The Mexican government tightened its laws against illegal fishing with a two-year ban on gillnets, identified as the single biggest threat to the species. However this ban is due to expire at the end of May.
Despite some efforts by the Mexican government, it has been unable to demonstrate effective enforcement of this temporary ban and this has resulted in unabated illegal gillnet fishing, causing vaquita populations to decline by 90 per cent between 2011 and 2016.
The rescue project – which has received $3m backing from the Mexican government and $1m from the US Association of Zoos and Aquariums – will involve researchers using acoustic sensors over the next few months to find the vaquitas and then, in October, they will try to catch individual specimens in nets.
Ten years ago a team was involved in an attempt to survey numbers of a similar cetacean, the Yangtze river dolphin – also known as the baiji. Its population was known to be threatened by the illegal laying of fishing nets. What the team found turned out to be far worse. “We didn’t see a single baiji or hear one whistle,” a team member told the Observer. “We were too late.” The baiji is now officially listed as extinct.
In the past, other species have been pulled back from the brink of extinction, Rojas-Bracho said. Hunting had reduced numbers of the northern elephant seal to a few dozen in the 19th century. Today, protected by law, there are more than 170,000 of them. “A similar story concerns the southern sea otter, which was reduced in number to around 50 but which has since bounced back to around 2,500 creatures,” he said. “This sort of thing can be done”.