Lorenzo Rojas-Bracho was in mourning. Beyond the windows of his hillside house in Ensenada, Mexico, the sun glinted brilliantly off the waters of the Pacific, but he’d drawn the curtains closed. In his living room, hanging above plush leather furniture, were whimsical paintings of the subject of his grief—a chubby, 4-foot-long porpoise called the vaquita (Spanish for “little cow”). Found only in the upper reaches of the Gulf of California, where the Colorado River meets the sea, the vaquita is the goth kid of the cetacean clan, with dark markings around its eyes and mouth and a reputation for extreme shyness. It is also the most threatened marine mammal on earth. Over the past 20 years, the species’ population has fallen by a staggering 98 percent. It’s officially listed as critically endangered, but even that term feels like a wild understatement; today there are perhaps a dozen vaquitas left.
Rojas-Bracho, a marine biologist, has been in love with aquatic mammals for most of his life. When he was 7 years old, he visited SeaWorld and offered his services as a killer whale trainer. (“They said no, of course, but they were very kind,” he recalled.) Now he is the head of the International Committee for the Recovery of the Vaquita and an idol among Mexican conservationists. A tall, wiry man with scholarly glasses, a salt-and-pepper goatee, and the disposition of a cool uncle, he takes a patriotic sort of pride in the porpoises. In the million years or so since their ancestors swam up into the Gulf, vaquitas have become exquisitely adapted to their special cul-de-sac: Their dorsal fins and flippers are proportionally bigger than other porpoises’, to dump heat when the water temperature breaks 90, and their echolocation is finer than a dolphin’s or a bat’s, allowing them to thrive in conditions so turbid that a diver just 15 feet down can’t see his own hands. What’s more, they’re cute. An old Gulf fisherman who was lucky enough to have seen one on a few occasions told me, “You almost want to cuddle it and pet it. It’s such a defenseless animal.”
Those who study the vaquita must handle disappointment well. But when I visited Rojas-Bracho in Ensenada, he wasn’t his usual stoic self. A few months earlier, in the fall of 2017, he and his longtime collaborator Barbara Taylor, a marine mammal geneticist at the Southwest Fisheries Science Center in La Jolla, California, had helped mount the first attempt to take vaquitas into captivity. With more than $5 million in funding from the Mexican government and outside donors, they had assembled a fleet of 10 boats, a custom-built floating porpoise pen they called el Nido (“the Nest”), and a team of 90 people from nine countries—acoustics experts, spotters, animal handlers, veterinarians—along with four US Navy-trained bottlenose dolphins. The project had ended in tragedy. “I still cannot talk about it without crying,” Rojas-Bracho said.
The captivity expedition had capped off nearly a century of trouble for the vaquita. Like tigers, elephants, rhinoceroses, and pangolins, all of which teeter on the brink of extinction, the porpoise has been obliterated, indirectly, by China’s reckless appetite for exotic animal products. In the 1930s, Chinese fishermen started landing huge catches of a giant croaker fish called the bahaba. The species, which grows to 6 feet long and weighs up to 220 pounds, was prized for its swim bladder, or maw, an organ that helps ballast the animal. Although made up mostly of collagen, maws of all kinds are a popular medicinal supplement; they’re sold dried and prepared in soup. Bigger is supposedly better, and the bahaba’s is huge. By the middle of the 20th century, overfishing had decimated the species, so maw traders turned to the next best source, an equally giant Mexican croaker called the totoaba. Every winter, it swam north to spawn off the coast of a small Gulf town called San Felipe, smack in the middle of the vaquita’s only habitat.
The ensuing gold rush was catastrophic for fish and porpoise alike. At first, the totoabas were so plentiful that they could be harpooned from the beach, butchered for their maws—which, when dried, resemble colossal potato chips with unappetizing tendrils—and left to rot. But as the population dwindled, fisherman turned to new methods. Near the Colorado River estuary, they laid gill nets, aquatic weapons of mass destruction designed to hang in the water column and ensnare passing prey. Vaquitas have the fatal misfortune of being nearly the same size as totoabas, so the nets were disastrous for them.