Environment

Thylacine Survey: Are We Going to Rediscover the ‘Moonlight Tiger’?

Reported sightings of the long-thought-extinct marsupial predator in remote northern Australia have drawn attention to a survey of the region, slated to begin next month.

Thylacinus cynocephalus. Credit: Wikimedia Commons

Thylacinus cynocephalus. Credit: Wikimedia Commons

The 1980s rock band Cinderella had its biggest hit with the song, ‘Don’t Know What You Got (Till it’s Gone),’ riffing off the age-old proverb. Of course, Cinderella’s song is about a love affair, but the sentiment could speak as easily to the state of the thylacine, once the world’s largest marsupial carnivore. Representing its own family, capable of opening its mouth 80 degrees, and striped like a tiger (or maybe the tiger is striped like a thylacine), the last one died in 1936 after a decades-long campaign to wipe out the animal as sheep-killing vermin. But true to human nature, people only really began to love the thylacine after it was gone. The species has since taken on a potent afterlife by capturing the public’s imagination and inspiring thousands of reported sightings of an animal that’s supposed to be dead and gone. It has become a favorite of cryptozoologists – people who believe creatures from folklore or history are still roaming the world undocumented – and of those interested in bringing back species from the dead via their DNA.

So, it’s not exactly surprising that when a team of scientists – serious scientists with impressive careers and credentials – announced they were planning to look for thyalcines (Thylacinus cynocephalus) in Cape York Peninsula on mainland Australia the news went global and the Internet a little wild.

But the media largely failed to report some important points: the survey was planned long before the thylacine became a part of it; the sightings of the purported thylacine were more than thirty years old; the survey is taking place in mainland Australia where the thylacine is believed to have gone extinct over a thousand years ago (not Tasmania where the last known individual was shot by a hunter in 1930); and those involved are keen in tamping down any expectation of them bringing home evidence of living, breathing, extinction-defying thylacines.

The survey will be taking place in northern Australia’s Cape York Peninsula, thousands of miles from the thylacine’s last stronghold of Tasmania. Satellite data show the region still boasts significant expanses of intact forest landscape — areas of native vegetation cover that are large and undisturbed enough to retain their original biodiversity levels. Credit: Google Earth

The survey will be taking place in northern Australia’s Cape York Peninsula, thousands of miles from the thylacine’s last stronghold of Tasmania. Satellite data show the region still boasts significant expanses of intact forest landscape — areas of native vegetation cover that are large and undisturbed enough to retain their original biodiversity levels. Credit: Google Earth

“We’ve always said that we think the probability of encountering a thylacine is very, very remote,” said Bill Laurance, a professor with James Cook University well known and long respected for his work on tropical ecosystems around the world.

“People are just going batshit over this thing and the reporting made it sound as though the thylacine was practically, just waiting out there,” he added.

Laurance is working on the survey with Sandra Abell, also a professor at James Cook University and one of the world’s foremost experts on bettongs, small marsupial rat-kangaroos that are threatened with extinction – but have received zero press compared to the thylacine.

To illustrate the chances of finding actually finding thylacines, Abell pointed to a study published soon after their survey announcement that calculated the chances of a thylacine surviving: 1 in 1.6 trillion.

“So my task is huge but tongue in cheek I say challenge accepted!” Abell, who will be leading the survey on the ground, wrote in an email. “If they are there we have a good chance of getting them on camera, if they aren’t nothing is lost.”

According to the study – entitled “The thylacine is (still) extinct” – the most optimistic view is that the thylacine survived on Tasmania unrecorded until the 1950s, but then – again most optimistically – met its end.

“There are a whole set of assumptions built into models like this,” Laurance said, “but I think it interjects a needed note of sobriety.”

Laurance and Abell are not saying there is any physical evidence that thylacines survive on Cape York today; what they do say is that two sightings from the 1980s are intriguing enough to investigate. This is, after all, what scientists do: investigate.

Seeing red

Hundreds – if not thousands – of people have claimed to have seen thyalcines since their extinction, but what really got Laurance and Abell’s attention was the purported eye shine of these mystery animals.

Thylacines could open their mouths 80 degrees. But while their maws were large, their jaws were relatively weak. Credit: Wikimedia Commons

Thylacines could open their mouths 80 degrees. But while their maws were large, their jaws were relatively weak. Credit: Wikimedia Commons

“Eye shine is a very distinctive characteristic when an animal is looking directly at you,” explained Laurance who has done spotlighting of animals at night around the world. “Species have species-specific eye shine features and they are even age specific in some species.”

This all started in March, when Brain Hobbs, a former tourism operator, went public with a story that he saw four thylacine-like animals on Cape York – two adults and two pups – in 1983 with red eye shine.

Red is key. If indeed the animals in question had red eye shine then what Hobbs saw was probably not dingoes, dogs or feral pigs, according to Laurance and Hobbs. Known animals in the Cape York rainforest with red eye shine include Lumholtz’s tree kangaroos (Dendrolagus lumholtzi) and the green ring-tail possum (Pseudochirops archeri), neither of which any experienced outdoors person would mistake for a thylacine.

“You got a guy who’s claiming credibly, on-the-record, both in an extended taped conversation and then later when I spoke to him at length in a very open-ended, very careful interview, who says that he’s got four individuals, twenty feet away looking straight at him. He’s dead certain, dead, dead certain, they were red eye shines,” said Laurance. “He says they are canid-sized animals and he saw distinctive lateral striping beginning from behind the front haunch going back to the backend of the animal. You know, that was when we said look.”

No one knows what color eye shine thyalcines actually had – it may not have been red. But Hobbs’ story – if true – means he wasn’t looking at an animal that researchers would most expect to be mistaken for a thylacine on Cape York.

The other sighting is from a ranger, Patrick Shears, who worked in Cape York during the 1970s and 1980s. He did not get the color of the eye shine, but he did see the animal at close range one night. He said indigenous people in the area know of it and call it the “moonlight tiger.”

Eyeshine is produced when light is reflected off the tapetum lucidum, a special layer of tissue behind the retina that helps provide night vision for many nocturnal animals. Humans and other primates lack the tapetum lucidum and, thus, eyeshine. Photo is of an aye-aye. Credit: Tom Junek via Wikimedia Commons

Eyeshine is produced when light is reflected off the tapetum lucidum, a special layer of tissue behind the retina that helps provide night vision for many nocturnal animals. Humans and other primates lack the tapetum lucidum and, thus, eyeshine. Photo is of an aye-aye. Credit: Tom Junek via Wikimedia Commons

Laurance said such sightings are “compelling” enough to “[make] the hair on the back of your neck stand up.”

Of course, this doesn’t mean Hobbs and Shears actually saw undead thylacines. Abell said it’s possible they were dingo-dog hybrids. Another option may be foxes. Fox can have red eye shine – and south of Cape York, thylacine sightings are often just foxes, especially those with mange, which makes them look striped like the thylacine. However, Laurance and Abell said to date there is little evidence that foxes can survive in Cape York.

“It’s just way too warm for them there – they suffer from all kinds of diseases,” Laurance explained. 

Feral cats are another possibility. But Laurance said, contrary to media reports, feral cats are not that common in some parts of Australia, including Cape York.

“I’ve done a lot of field work – three years of field surveys across a lot of these different regions – and you just don’t find many feral cats,” he said, adding that he didn’t think experienced observers like Hobbs and Shears would confuse a cat for a thylacine.

“We still regard this as highly unlikely,” he cautioned. “Cops will tell you that human observers are just inherent unreliable.”

However, he added, those observers who are “the most unshakable and detailed…are the most credible.”

For Laurance, Hobbs and Shears fit this latter category.

But what they saw could still fall under any number of things. It’s possible they saw a new, undescribed species. It’s also possible that they did see thylacines, but the animals are since gone. Scientists believe that thylacines went extinct on the mainland around a millennium ago in part due to competition from bigger and more adaptable dingoes, which humans brought to Australia 4,000 years ago (there are no dingoes in Tasmanian and experts say that’s why it was able to persist there so much longer). But dingos are present on Cape York, making it harder to imagine the thylacine’s survival there. And, perhaps even more worryingly, small mammals on the peninsula are vanishing, which means that if thylacines somehow survived in this unexplored wilderness until the 1980s – they may not have been able to hold on during the last thirty years given ongoing prey decline.

But even if the team doesn’t rediscover the thylacine, it has much to discover.

Just as excited for bettongs

The primary objective of Abell and Laurance’s survey has always been to gather better data to answer the question: why are so many of Australia’s native mammals vanishing? But the thylacine news has usurped this objective, swamping out news of all the other species the researchers are looking for.

One species the team hopes to document is the northern bettong (Bettongia tropica). Currently classified as Endangered by the IUCN Red List, Abell said it’s only known from two locations, including one population she recently helped discover on Mount Spurgeon. Abell said she would be “as excited” to find the northern bettong in Cape York as the thylacine. Admittedly, she is probably alone in this sentiment, but it shows just how keen the researchers are to document any animal on the peninsula that hasn’t been cataloged yet, especially threatened ones.

Indeed, the team has a list of 74 mammal species they will be looking for on the Cape York Peninsula, some of them native and endangered and some invasive and potentially damaging to local wildlife. Whatever they find – thylacine or not – it will help them better understand what’s behind the mammal decline in northern Australia.

Researchers have put forward a number of ideas on why mammals are declining, including cattle grazing, invasive plants, drought, changes in fire regimes and predator pressure from animals like fox, cats and dingoes. Abell said that in the case of northern bettongs, she feels that habitat changes due to fire regimes and cattle grazing is key. However, she added that one possibility that that needs more exploration is disease. 

What the addition of the thylacine has changed – aside from media coverage – is the intensification of the survey and some of the specific areas that will be explored.

“There are huge areas of the Cape that are still very poorly explored biologically,” Laurance said, adding that the thylacine sightings have provided a “rationale” for using helicopters to get into some of the most remote areas of the peninsula. A number of ranchers in the area employ helicopters to wrangle cattle.

Cape York is arguably the wildest place in Australia and the least explored, so if thylacines – or an undiscovered population of northern bettongs – are hiding out anywhere, it’s most likely here.

“There are weird things popping up. There’s two or three species being found every year on Cape York peninsula – new species of frogs and lizards,” Laurance said.

Heading out next month, the team plans to strategically place around 50 camera traps on the ground along with scent baits to attract carnivores. They will leave out the traps for two to four weeks before collecting them again. They also plan to do spotlighting on foot to see what they can find in person.

“[Sandra Abell] and I have both discovered or rediscovered presumed extinct populations of things, or gigantic range extensions of things,” said Laurance, adding, “new stuff is being found.”

Indeed, in 2013 wildlife photographer, John Young, got photographic evidence of the night parrot, a species in Australia that no one had confirmed since 1912. The night parrot came back from the dead after being “gone” for a longer time than the thylacine has. However, it’s also easier for a bird to stay hidden than a good-sized carnivore – and the night parrot was never officially declared extinct as credible sightings trickled in over the decades.

All this is to say, while it’s not likely the thylacine will be discovered – it’s not impossible either. After all, what would scientists have pegged the chances of a fisher pulling up from the sea a coelacanth, a fish that was supposed to have gone extinct 66 million years before?

Maybe 1 in 1.6 trillion?

Abell promised that if thyalcines are still roaming Cape York, “I will find them.”

And if they aren’t?

A thylacine family in a zoo in Hobart, Tasmania, 1910. Credit: Wikimedia Commons

A thylacine family in a zoo in Hobart, Tasmania, 1910. Credit: Wikimedia Commons

“I [will] still have important data that will be useful and help inform my projects on declining mammals.”

What if the unimaginable happens?

Around a thousand years ago, the thylacine was wiped out from most of mainland Australia. Victims of humans, dingoes and ongoing prey decline, most thylacine populations winked out like cities going dark. But we know that even as that happened, a population survived offshore in Tasmania for nearly a thousand years.

Now let’s say – hypothetically – a small population also survived in the wilds of Cape York.

Let’s say this Cape York population became adept at avoiding humans and dingoes; let’s say it only came out at night and stuck to well-known paths where it could hide from predators and competitors with ease; let’s say, in a sense, these animals learned to become living ghosts – this is not contrary to the literature on thylacines, which considers them nocturnal and shy. And as the peninsula filled up with cattle – as forests were felled – this small population retreated to the refugia of still-standing forests and continued, there, to hunt, to breed, to survive – unnoticed by the ever-spreading Homo sapiens.

Let’s say, however, that many aboriginal people knew this animal persisted, but held their tongues – knowing it was rare and threatened. Plus, when they talked, few outsiders believed them. Let’s say a few wilderness-lovers like Hobbs and Shears saw these animals, these thyalcines – but kept it quiet for decades because they didn’t want to be labeled as kooks (because that’s what happens when someone says they’ve seen a thylacine).

Now let’s say, against all odds, this small remnant population somehow squeezed through the last few decades – until a troupe of scientists showed up with camera traps, bait, and a local knowledge of just where these sightings occurred. Let’s say one moonlit night, a young animal, tiger-striped and pouched, walks along its silent trail until it crosses a laser that triggers the camera – and boom. Photographic proof. The thylacine is back.

Now, what the hell happens?

“Silence would be the best indicator that we actually discovered something interesting, whether it was the thylacine or something else,” Laurance said. He explained that if they got a good photo there would likely be a “government lockdown” on the news for months.

“There would be some really serious behind-the-scenes discussions and you’d probably go out and put out a bunch of hair traps to make sure you’ve got DNA samples just to verify it. And then it would be some really serious thinking about what to do about it.“

Scientists would try and answer basic questions under a veil of silence: what the thing actually is (Abell said if they do find a thylacine it would probably be a subspecies or even a different thylacine species than the one that existed in Tasmania), where exactly it occurs, and how threatened it is. Protection would come immediately.

“My first concern would be to ensure that in the short term the habitat is protected and security provided to prevent too many people trying to get access to the area,” Abell said.

“My main concern is to make sure it doesn’t turn into some kind of a circus,” Laurance said.Then would begin quiet negotiations with stakeholders, in this case likely indigenous groups, landowners, cattle ranchers, and maybe even mining concessions.

And the end result? Both Laurance and Abell said a World Heritage Site designation could be a real possibility. And once the world knew, the region would have to figure out how to deal with a meteoric rise in people wanting to show up and have their own encounter with the moonlight tiger.

The last thylacine killed in the wild was reportedly shot by farmer Wilf Batty in 1930. In the unlikely event of a thylacine rediscovery, researchers say they hope the government would enact swift, strict protections. Credit: Wikimedia Common

The last thylacine killed in the wild was reportedly shot by farmer Wilf Batty in 1930. In the unlikely event of a thylacine rediscovery, researchers say they hope the government would enact swift, strict protections. Credit: Wikimedia Commons

And then everyone will have to figure out how you protect a species that will suddenly become the most famous and desirable animal on the planet – overnight.

 “But that’s ‘if’ built upon ‘if’ built upon ‘if’ built upon ‘if’ built upon ‘if’. There are a whole series of ‘if’s that would have to align,” cautioned Laurance, who told New Scientist that he thought the actual chances of rediscovering the thylacine were one to two percent. Not one in 1.6 trillion.

“We’re not talking about Loch Ness Monster here, we’re not talking about yetis, something that has never been documented. We’re talking about something that was known to have [existed],” he said.

If the discovery happened, it, according to Laurance, would be “world changing” in how scientists view extinction. He said it would also give the world a much-needed dose of optimism when it comes to our global mass extinction crisis, and would likely spur a frenzy searches for other supposedly vanished species.

But for all the excitement, all the hope, all the hype, all the fun what-ifs, Laurance wants to make sure people really understand that the thylacine is most likely still extinct. It’s easier, probably, to explain various sightings – even those experienced by veterans – than to assume an animal of this size survived a thousand years undocumented in Australia.

“I had this documentary guy came to my house, he said ‘what do you think the likelihood of this is?’,” Laurance said. “And I said ‘somewhere between exceedingly unlikely and vanishingly unlikely.’ And he was really disappointed. And I said, ‘well that’s just the truth. That’s the reality’. If you want to do a documentary on this you’d better make it like the Blair Witch Project because you’re probably not going to see the witch.”

In Cinderella’s song, the rock band sings, “Now I know what I got / It’s just this song.” That’s probably all we have left of the thylacine – just remnants: a few stuffed dead animals, some written accounts, our overactive imaginations. Perhaps the best lesson from all this will be that we lost the thylacine due to ignorance, greed, and cruelty – so maybe we should be doing a lot more to save other species on the edge, like the vaquita, the saola, the Hula painted frog, and the giant ibis.

But while there’s wilderness, there’s hope. Hope that every night when we go to sleep and dream, some mysterious mammals – tiger-striped and large-mawed – emerge from their dens and go hunting, their breath vanishing in the cool night air.

William Laurance is a member of Mongabay’s advisory board

This article was originally published on Mongabay. Read the original here.