Fewer than 500 black-winged mynas remain in the wild in Indonesia, but each year more of the songbirds are captured and sold as pets.
Banteng — “the most beautiful and graceful of all wild cattle,” according to the World Wide Fund for Nature — were listed as endangered in 1996, but their horns still are sold in markets across Southeast Asia.
And the critically endangered giant carp, a Mekong River native that can weigh up to 600 pounds, recently began turning up on restaurant menus in Vietnam. Experts warn that the fish might soon be pushed into extinction.
International trade poses a threat to all of these species, yet not one is subject to key regulations that would help protect it. They are not listed under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (Cites), a treaty meant to ensure that trade does not imperil the survival of threatened and endangered species.
These are not isolated cases: Cites oversights are all too common for many of the world’s endangered species, conservationists warn. “There’s a backlog of species that are being over-exploited and traded internationally, but lack protection,” said David Wilcove, an ecologist at Princeton University.
“Wildlife trade is a threat equal to or greater than habitat destruction for many species, and it’s not going to get any better unless countries step up,” added Dr. Wilcove, co-author of research into the problem published recently in the journal Science.
Cites protects thousands of animal and plant species by barring trade of the most highly endangered and by sustainably regulating the others. But as conservationists have repeatedly pointed out, the treaty neglects entire classes of animals, including 92 percent of the world’s 10,700 reptile species, most amphibians, songbirds and fish, as well as invertebrates and small mammals.
In their study, Dr. Wilcove and Eyal Frank, an environmental economist at the University of Chicago, sought to detail the disconnect between scientific data and action taken to protect plants and animals threatened by international trade.
The researchers first consulted the International Union for Conservation of Nature’s Red List, the authority on the conservation status of the world’s species. The scientists zeroed in on those listed between 1994 and 2013 as threatened with extinction, and then narrowed their focus to species jeopardized by the international wildlife trade.
Of the 958 species in their sample, 28 percent were not protected under Cites, the researchers found. On average, it took Cites more than 10 years to catch up with the Red List’s assessment that a species risked extinction.
The lag can contribute to the decimation of a species. “Spending even just a few years without protection and regulation on trade can lead to large detrimental effects on the wild population of a species,” Dr. Frank said. “Trade can escalate very quickly.”
To bridge the gap between science and policy, Dr. Frank and Dr. Wilcove propose strengthening the exchange of information between Cites officials, member countries and Red List researchers.
But greater awareness will not necessarily hasten new listings, because Cites members consider more than just science when it comes to making decisions, said Julie Lockwood, an ecologist at Rutgers University who was not involved in the research.
“Every country is weighing the biological risk with the commercial risk, because people are making money off these species,” she said.
To add a species to Cites, one or more governments must submit a detailed proposal in advance of the next major conference of the parties, held every two to three years. Nations attending the conference vote on the proposals, which require a two-thirds majority to pass.
While countries are supposed to vote based on the scientific merits, “we all know that’s looking at the world through rose-tinted glasses,” said Bruce Weissgold, a former senior Cites specialist at the Fish and Wildlife Service. “Science and Cites can be uncomfortable bedfellows, particularly when someone comes between them.”
Cites representatives often vote based on national interest, or even personal interest, Mr. Weissgold said — a problem he believes has worsened over the last decade or so. Vote trading between nations is not uncommon, he said.
Sometimes, economic and political obstacles can be overcome. Japan, China and other nations put up “tremendous resistance” to proposals seeking to protect shark and ray species under Cites, said Susan Lieberman, vice president of international policy at the Wildlife Conservation Society.
But in 2013, member nations voted to add seven species of threatened sharks and rays to the treaty, followed in 2016 by four additional shark species and all devil rays.
In other cases, however, commercial interests prevail. Red and pink corals — species imperiled by over-harvesting to make jewelry — have been nominated twice, but both proposals failed to pass following intense lobbying by the coral trade industry.
Trade continues to impact many of these coral populations, but Dr. Lieberman has heard of no plans to renominate them.
“What country wants to go through that again?” she said. “There are times when a species qualifies and there’s no question they qualify, but you just can’t get over the two-thirds majority needed for a proposal to pass.”
This May, Cites member countries will meet in Sri Lanka to consider a new batch of proposals. Protections for black-winged mynas, banteng and giant carp are not on the agenda.