Zoos may have once been considered a safe haven for animals threatened by poachers, but the shocking crime at a zoo outside Paris, in which a white rhino was killed and his prized horn sawed off, has changed things. Now conservationists are calling for better protection for the endangered animals — and education to end superstitious belief in rhino horns' "healing powers," which fuels poaching.

In a report from France-based international news agency AFP, conservation organization Robin des Bois “recommends ramping up zoo patrols and giving guards the right to fire warning shots.” Outside of zoos, the group called for tighter security for customs and postal services to prevent sales of rhinoceros horn; and public education to show people that the horn “does not have any of the healing powers it is credited with.”

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“If this first blow [for zoo rhinos] is not followed with rigorous security measures, it is certain to be repeated in another zoo in France or in Europe,” Robin des Bois spokeswoman Charlotte Nithart told AFP. The agency noted that criminals have stolen living animals from European zoos before, including monkeys and penguins.

In the case of the white rhinoceros, a 4-year-old named Vince, media reports say poachers broke into the Thoiry Zoo on the night of March 6, shot Vince in the head three times and then hacked off one of his horns with a chainsaw. NPR reported that the raiders attempted to cut off the animal’s second horn as well but did not finish the job, either because they were scared off or their equipment stopped working. Two other rhinos that shared an enclosure with Vince were unhurt.

The zoo said in a statement on Facebook, “Vince was found this morning by his caretaker who, very attached to animals which she attends, is deeply affected.”

The World Wildlife Fund lists the white rhinoceros, which mainly lives in South Africa, Zimbabwe, Namibia and Kenya, as “near threatened,” and Vince’s killing in the Thoiry Zoo is the latest in a series of setbacks for the species. That organization describes the animal as “a major conservation success story, having been brought back from the very brink of extinction,” but notes that poachers are more a threat now than ever.

They were actually thought to be extinct at one point, thanks in part to hunting, until a small group of the rhinos were discovered in 1895. In today’s world, there is demand for rhino horn in the Asian market, where followers of traditional medicinal practices believe powdered horn can cure various ailments and is a status symbol.

“Hundreds of white rhinos have been killed annually in recent years,” the World Wildlife Fund says. “They are particularly vulnerable to hunting, because they are relatively unaggressive and occurs in herds.” That’s despite their size — up to 7,200 pounds and as tall as 6 feet. Their front horn, on average, is 2 feet long but could grow as big as 5 feet, and it’s made of keratin, a protein found in human nails and hair that protects from damage.

According to the AFP report, the European Union police agency Europol has previously warned that zoos could become a target for poachers as rhinos in African game parks become harder targets, surrounded by guards, and Vince’s killing marks the first time this has happened.

“There are about 160 rhinos in European zoos — a potential goldmine for horn smugglers,” AFP says.

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