Fewer than 100 Sumatran rhinos (Dicerorhinus sumatrensis) remain in the wild, a number many biologists say is too low to ensure the survival of the species.

Several organizations have begun to build momentum toward a single program that pools resources and know-how in Malaysia and Indonesia, the last places in Southeast Asia where captive and wild rhinos still live.

Advocates for intensive efforts to breed animals in captivity fear that an emphasis on the protection of the remaining wild animals may divert attention and funding away from such projects.

They worry that if they don’t act now, the Sumatran rhino may pass a point of no return from which it cannot recover.

LAHAD DATU, Malaysia – The rhino breeding center near the entrance to Danum Valley Conservation Area sits like an oasis of calm against the cacophony of beeps, woots and zaps of the surrounding jungle.

So calm it’s eerie, in fact. No one is working on the grounds. There are no animals in the collection of holding pens and chutes. Despite a few spots of rust, the green paint shows none of the wear that would have come with housing cow-size animals. A silent generator sits in the corner, and the whole area is surrounded by heavy cable fencing that’s never been tested.

On a side of the road sits a sign that reads, “THE DANUM VALLEY BORNEO RHINO SANCTUARY, DVBRS.” The text explains that I’m looking at the site of the breeding program for the Bornean rhinoceros, but a parenthetical below notes, “THERE IS NO RHINO IN CAPTIVITY AS YET.”

In the three years since the center’s construction not far from the town of Lahad Datu, the Bornean subspecies (Dicerorhinus sumatrensis harrissoni) of the Critically Endangered Sumatran rhino (Dicerorhinus sumatrensis) has only grown more elusive. Most experts agreed in 2015 that the only ones still living in Malaysia were the three captive rhinos in an enclosure at Tabin Wildlife Reserve, east of the town of Lahad Datu. Sadly, that number is down to two: Puntung, a 25-year-old female captured in Tabin in 2011, had to be euthanized in early June, shortly after being diagnosed with terminal cancer.

I’d come to Danum Valley in part to follow up on a revelation that one more rhino might still be lumbering around the valley’s old-growth forests. In 2016, a team of scientists announced that they had found something resembling a rhinoceros print in the 438-square-kilometer (169-square-mile) reserve. It touched off a flurry of speculation – mostly by journalists like me – that a remnant population of rhinos may be hiding out in Danum.

But since learning of the possibility, I hadn’t been able to find anyone to tell me more about what it might mean. During a recent trip to Sabah, the WWF scientist who led the expedition turned down my request for an interview. And others scoffed at my naïveté when I brought up the “discovery.”

Footprint or fabrication?

In fact, it seemed that many conservationists believe that this apparition – this potential figment that could have just as easily been from a small elephant as from Borneo’s diminutive, shaggy rhinos – could actually be a detriment to the species’ survival, rather than a sign of hope.

The footprint, publicized at a press conference, crystallizes a decades-old struggle over how best to ensure the survival of these animals. Should managers do all they can to maintain wild populations? Or should they gather the surviving holdouts and help them reproduce?

Those in the latter camp write off the print as a myth that’s skewing the focus – and funding dollars – of conservation away from where it should be.

“The ‘rhino’ is a fabrication,” John Payne told me in an email. “[People] keep doing that.”