Scientists have abandoned their attempts to save the world’s last vaquita porpoises, in a heartbreaking moment for animal conservation.

VaquitaCPR, a $5 million initiative by the Mexican government and conservationist to save the vaquita, will announce the end of the project today. This is following the death of a female vaquita on November 5, which we reported yesterday.

Less than 30 of the animals are thought to still exist in the world, having numbered 567 in 1997, pushed towards extinction by human activity. Many have fallen prey to fisherman trying to illegally catch the highly prized totoaba fish, which lives in the same region of the Gulf of Mexico. Vaquitas are the smallest species of cetacean on Earth, and also the most endangered.

So in an effort to save the species and boost population numbers, this project sought to establish a captive breeding program in a sea pen. Two vaquitas were captured, including a calf in October, but it had to be released when it became too stressed. The other, a female, died before she could be released back into the wild.

“There’s nothing worse than having an animal die in your hands,” said Frances Gulland, the lead VaquitaCPR veterinarian and a scientist at the Marine Mammal Center in Sausalito, California, reported Science.

So the team has now decided the project is not worth the risk. Instead, the team will focus their efforts on trying to capture photographs of the remaining animals, so that they can be tracked. They will also aim to count the remaining animals with underwater listening devices, and they may also name them to increase public interest.

“We do know we won’t be attempting any more captures [anytime soon],” Randy Wells, a VaquitaCPR leader and director of the Chicago Zoological Society’s dolphin research program in Sarasota, Florida, told The Washington Post.

But, he added, broadcasting to the world that “there are so few of them that you can essentially give them all names is something that will cause more people to embrace their plight.”

It’s a tragic end to this conservation program, but Gulland is now calling for more enforcement against illegal poaching to potentially save the species. Their numbers have continuously dropped, though, and the signs do not look good. Conservation efforts have now, inadvertently, brought this species one animal closer to extinction.