A rare Sumatran rhinoceros has died in Indonesia, less than a month after its discovery and capture were hailed as an enormous conservation success for a species long believed to be extinct in the region.

The female rhino died from a leg infection, Indonesian environment officials told Agence France-Presse. On Wednesday, the World Wildlife Fund-Indonesia’s conservation director, Arnold Sitompul, said that although the death was still being investigated, it appeared the infection was “severe,” and may have been “caused by snares from an earlier poaching event.”

“This demonstrates the threats faced by the Sumatran rhino and underscores why we need to continue our efforts with the strong support of the government and other experts to save the remaining population of Sumatran rhinos in the area,” Sitompul said.

Sumatran rhinos — the smallest and hairiest of the five rhinoceros species — were once abundant in Southeast Asia. But poaching and habitat destruction from mining and agriculture depleted their population, and last year, the Malaysian part of Borneo island declared them extinct in the wild.

Conservationists also weren’t sure the elusive animals still existed in the Indonesian Borneo, known as Kalimantan. But in 2013, remote cameras captured images of one and estimated that there might be about 15 in the Kalimantan wilds. Another 85 or so live in Sumatra.

And then, on March 12, humans made contact with a Sumatran rhino in Kalimantan for the first time in 40 years, when the female was captured there in a pit trap.

The World Wildlife Federation lauded the capture as “a major milestone for rhino conservation in Indonesia.”

“This is an exciting discovery and a major conservation success,” Efransjah, the chief executive of WWF-Indonesia, who has only one name, said at the time. “We now have proof that a species once thought extinct in Kalimantan still roams the forests, and we will now strengthen our efforts to protect this extraordinary species.”

The WWF said the female would be moved by helicopter to a “protected forest” about 90 miles away, where it would be the first rhino in what would become Indonesia’s second Sumatran Rhino Sanctuary. On Tuesday, the International Rhino Foundation, which is a partner in the country’s existing Sumatran Rhino Sanctuary, lamented the captured rhino’s death in a Facebook post and suggested that it might have been prevented had the animal been taken to the established facility.

Our hearts are saddened by this devastating news from Kalimantan. There are many lessons to be learned from this event….

Posted by International Rhino Foundation on Tuesday, April 5, 2016

“It is our hope that the next rhino captured in Kalimantan will be sent to the Sumatran Rhino Sanctuary where it can be cared for in a permanent facility by experienced veterinarians and keepers,” the foundation wrote.

Tachrir Fathoni, a senior official in the Indonesian environment ministry, told AFP that the rhino’s death had not been in vain.

“The death of this Sumatran rhino proves they exist on Borneo, so we will continue protecting them,” he said.

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