With some scientists predicting a sixth mass extinction, the world’s protectors of wildlife acted with a greater sense of urgency at a marathon meeting to toughen regulations against killing such endangered animals as sharks, manta rays and anteaters and trading their remains.

By the time the gathering in Johannesburg ended a day early  Tuesday, the Convention on International Trade in Endangered Species, or CITES, had issued several trade bans, including one for the African grey parrot, favored by animal lovers for its ability to mimic human speech. CITES also moved to shut down the black-market trade of an exotic anteater called the pangolin, which is killed and sent mostly to China so its scaly skin can be roasted for traditional medicine.

“With 183 parties bound by the convention, CITES is the largest conservation agreement in existence,” said Adam M. Roberts, chief executive of Born Free USA. “This meeting represents a clear win for conservation overall — but much work remains.”

Conservationists hailed the convention’s 17th meeting, where two African governments were barred from selling their stockpiles of ivory and another from trading away stockpiles of rhino horn, as the most progressive on behalf of animals.

“It was a very jam-packed conference,” said Jeff Flocken, North America regional director for the International Fund for Animal Welfare. “This is one where conservation was at the forefront of people’s minds for animals that everyone cares about.” Numerous species that generally are unknown to the public, including the pangolins, thresher sharks and Barbary macaques, “came away with some very strong protections,” he noted. 

Delegates at the convention called on Mexico, the United States and China to join forces to block the trade of totoaba, which Mexican fishermen poach with nets for an Asian market, in the process drowning the world’s smallest porpoise, the vaquita. Only 60 vaquita remain.

The convention also beat back a proposal by Swaziland to sell legally collected rhinoceros horn that could have masked black-market sales that drive poachers to slaughter at least three of the animals each day. Among other important actions on elephants, it decided to block Namibia and Zimbabwe from selling legally collected ivory for fear that that would provide cover for the illegal trade.

Nearly 150,000 African forest and savanna elephants have been slaughtered for their tusks in the past decade. In a last-minute reversal, Botswana, home to the largest populations of elephants, broke from a coalition of nations pushing for the sale of ivory and argued against it.

But Flocken called the convention’s moves “a mixed bag” because it defeated a proposal to afford elephants the treaty’s strongest protections under Appendix I.

Not every conservation organization expressed the same level of disappointment. The World Wildlife Fund said the decisions on elephants “have closed all potential avenues to a resumption in international ivory trade, paving the way for the world to unite behind efforts to crack down” on the ivory trade.

“Now that the debate over whether to trade or not to trade is over,” said Ginette Hemley, who headed the organization’s delegation, “countries around the world must turn the tough talk we have heard here in Johannesburg into tough measures on the ground.”

Conservationists faulted the convention for not specifically prohibiting trade of the bones of captive lions in South Africa. Asian markets that covet the bones of tigers, which have mostly disappeared, have turned to the bones of lions and cheetahs for delicacies and cures.

But victories overshadowed defeats. CITES took steps to stop mobula rays and devil rays from going from this:

To this:

Fisheries must now prove that populations of nine species of mobula rays are sustainable, meaning they can recover from large-scale fishing, before they can be taken or traded. Rays were added to the list of species afforded the world’s second-strongest protections under Appendix II.

Thresher sharks, valued for the exquisite long tail that they snap to catch prey, won similar protections. “This vote is a huge step towards ensuring the survival of these larger shark and ray species, which continue to be at greatest risk of extinction because of the value of their fins and gills,” Luke Warwick, director of the global shark conservation campaign at the Pew Charitable Trusts, said in a statement. “The call from a record-setting number of governments to protect these species has been answered.”

Noting the failure of past efforts to protect African grey parrots, CITES banned their trade completely, allowing governments such as the United States to keep the birds from crossing international borders.

“Fraud and corruption have enabled traffickers to vastly exceed current quotas and continue to harvest unsustainable numbers of African grey parrots from Congo’s forests to feed the illegal trade,” said Colman O’Criodain, the World Wildlife Fund’s global wildlife policy manager.

“A total ban on international commercial trade . . . is a huge step forward and will help to protect this extraordinary species from the rampant trapping and trading that has contributed to population collapses and local extinctions across Africa in recent decades,” O’Criodain said.

Read more: