After Minnesota dentist Walter Palmer killed Cecil the lion last month, the popular animal was reportedly beheaded and the carcass left behind "to rot in the sun."
What was discarded by the trophy hunter is becoming, however, a valuable commodity, according to conservation organizations.
Vivienne Williams, a researcher at the University of Witwatersrand in Johannesburg, South Africa, said lion skeletons are increasingly being used in traditional medicine in Asia, replacing the bones of other threatened animals.
"It appears as if in many cases [the lion bones are] being substituted for tiger bones," Williams told VICE News. "So there seems to have been this sort of switch, where they substituted other large carnivores, until eventually they started using lion bones."
Williams was the lead author on a report about the trade in lion bones published by conservation groups TRAFFIC and the Wildlife Conservation Research Unit. Consuming tiger — and now lion — bones, rhino horns, and other animal parts is thought to be a remedy for all sorts of health ailments and an indicator of high social status in some Asian countries.
Over 1,100 lion skeletons were legally exported from South Africa to Asia between 2008 and 2011, according to the study. In 2008, 50 skeletons were exported, growing to 573 skeletons in 2011.
Williams said that while there are multiple complex factors behind the lion-skeleton trend, one of them is that measures put in place over the past two decades to protect Asian tigers could have led to lion bones being used instead. While the report's data focuses on the period between 2008 and 2011, lion-skeleton exports to Asia are still occurring, she warned.
"What seems to be happening is that the skeletons are a byproduct of the trophy-hunting industry [in South Africa]," Williams told VICE News.
Across Africa, lion populations are in decline and the International Union for Conservation of Nature describes the animals as "vulnerable."
Jimmiel Mandima, a program director with the African Wildlife Foundation, said African lions face numerous threats, including destruction of their habitats, diseases, and retaliatory killings when they kill farmers' livestock.
Mandima said his organization is "very concerned" about the continent's lion populations.
Craig Packer, the director of the Lion Research Center at the University of Minnesota's College of Biological Sciences said the situation for lions varies from country to country.
Populations in West Africa are "almost gone," he said, while in Central Africa they are "doing very, very poorly." In East Africa, lions are "dropping rather alarmingly." Comparatively, though, lions are doing better in the southern part of the continent: South Africa, Namibia, Botswana, and Zimbabwe. That's because a greater amount of fencing separates the animals from people, which helps reduce potentially deadly interactions, and population densities are lower in those countries, except for South Africa.
The South African trophy-hunting industry breeds lions in captivity and allows wealthy hunters to kill them in exchanges for a fee — a practice called "canned hunting," Packer said.
"It's kind of like shooting fish in a barrel," he told VICE News.
The lion-skeleton trade, he said, is tied to the growing canned hunting business.
"It's such a large market and these guys are breeding so many lions that they're able to enhance their bottom line by selling the bones to the Chinese and Asian market for a substitute for tiger bone in tiger bone wine," he said.
"I haven't been able to confirm a single case of a wild lion definitely being shot deliberately in order to get its bones out to Asia," he added.
He struck a note of caution, however: Now that the market for lion skeletons is on the rise, if there were to be some supply disruption, buyers might begin to seek out wild lions.
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