MEXICO CITY – A Gulf of California harbor porpoise, the most endangered marine mammal in the world, died during an operation to save the species, Mexican environmental officials and the international team working on the project said in a statement.
“This project brought together the world’s top experts on marine mammals to determine whether (the species) could be saved under human care. No conservation project like this has been tried before, and the operation carried significant risk,” the Environment and Natural Resources Secretariat and the Vaquita CPR team said.
The international rescue team said it was “inconsolable over the devastating loss” of this Gulf of California harbor porpoise, known in Mexico as the “vaquita” (sea cow).
Scientists, however, have concluded that the risky rescue operation is warranted given the dwindling number of vaquitas.
The adult female vaquita, which was not pregnant or lactating, was captured on Saturday afternoon and taken to the floating aquarium built in the Upper Gulf of California.
“The marine mammal veterinarians monitoring the vaquita’s health noted that the animal’s condition started deteriorating and decided to release it. This effort was unsuccessful and all measures were taken to keep the animal alive. Despite the veterinary team’s heroic efforts, the vaquita did not survive,” the team said.
Over the past few months, the government and its conservation partners built a floating aquarium 1.5 nautical miles offshore at a site protected from strong winds by El Machorro hill in Baja California state.
The floating aquarium, which is 4 meters (13 feet) deep, has areas for marine biologists and veterinarians to observe the vaquitas.
Under new regulations, boats will not be allowed to enter the area between Oct. 11 and Dec. 17, and officials have also banned fishing and tourist activities during that period.
On Oct. 12, the government, working with experts and scientists, implemented the Conservation, Protection and Recovery (CPR) project, which is designed to save the last vaquitas in the wild and relocate them temporarily to the floating aquarium in the Upper Gulf of California while officials work to remove fishing nets, the main threat to the marine mammals, from the ecosystem.
Many of the fishing nets that threaten the vaquitas were used by fishermen going after the totoaba, an endangered fish species that is highly prized on the black market, where it sells for thousands of dollars per kilo.
The vaquita is threatened by fishing in its habitat in the Upper Gulf of California and Colorado River Delta Biosphere Reserve in the Gulf of California.
Vaquitas, protected under the Convention on International Trade in Endangered Species of Wild Fauna and Flora, grow to around 1.5 meters (5 feet) and weigh up to 50 kilos (110 pounds).
The vaquita reproduces slowly, giving birth every two years, and the marine mammals are considered the most endangered cetaceans in the world.
Listed as endangered since 1976, fewer than 100 vaquitas are believed left in Mexico.