The thylacinid – or “Tasmanian tiger” – was declared officially extinct in 1986, 50 years after the last one was seen alive. And yet, some people hold out hope that these iconic marsupials are still out there somewhere, encouraged by a regular influx of blurry videos and images that bear some resemblance to the lost creatures. As yet, none of these alleged sightings has ever been confirmed.

Here’s some of the latest such footage, taken in late June by photographer Paul Day, who was exploring an area near Moonta, South Australia when an animal caught his attention.

"At first I thought it was a fox crossing in front of the sun," Day told the local news, "then I thought that it might have been a dog." But when he saw other possible thylacine videos online, he became convinced the animal was the same sort of creature.

Not surprisingly, this footage has been received enthusiastically by other thylacine-watchers, including Neil Waters, the founder of the Thylacine Awareness Group of Australia. Waters told a local reporter that his eye was drawn to some seemingly thylacine-like features of the creature in the video, including the shape of its tail, its head (which Waters described as “boofy”), and the peculiar way it walks, bouncing off of its back legs. He said that “many people who say they’ve seen a thylacine described it as moving in this way.”

But, as with so many similar videos, there is plenty of doubt around the identity of this boofy-headed silhouette. The fact that this video was taken on the Australian mainland, where evidence suggests thylacines have been gone for about 2,000 years, makes the alternative identifications (such as a dog or fox, as Day initially thought) seem much more likely.

I spoke with Chris Rehberg – founder of the website Where Light Meets Dark, which investigates and researches rare animals of Australia  who has taken the time to scrutinise the new footage carefully.

“Without a rigorous analysis, the morphology of the animal appears to match a fox better than a thylacine,” Rehberg says. “The animal's gait, which is notable, is more likely due to illness or injury than to the animal's identity being of marsupial origin.”

Another investigator with a similar opinion is Brendan Kays, who wrote a detailed analysis of the Day video on Rehberg’s site. Kays notes that the strange movement of the shadowy quadruped is less like the bounding walk of a thylacine and more like the crippled gait of a canid (fox or dog) suffering from hip dysplasia – a condition where the hip socket doesn’t fully support the thigh bone. And unlike the thylacine, foxes and dogs are well-known to roam the continent today.

All of this in-depth analysis and discussion raises the question: how could we confirm the presence of thylacines? Day and Waters reportedly went out looking for scat and tracks after this video was taken, and they are certainly not the first people to go on a thylacine-seeking mission. Over the years several official search parties have gone out into possible thylacine territory, including one earlier this year, but so far, none have come back with hard evidence.

Rehberg has been working on a project that, at the very least, can offer a way to learn more about these likely-departed creatures: he’s been studying their hair.

After acquiring a thylacine hair sample from an antiques dealer, Rehberg was inspired to use it to compare with unidentified hairs found in nature. With some generous assistance from the Commonwealth Scientific and Industrial Research Organisation, he was able to confirm through microscope analysis that his sample does indeed match the particular cuticle structure of a thylacine.

A microscopic photo of a thylacine hair. Image: CSIRO / Where Light Meets Dark (used with permission).

If thylacines are truly running around out there somewhere (perhaps in Tasmania, where they still lived only a century ago), they should be leaving behind not only footprints and feces, but also fur. Rehberg’s own data could be a great help in confirming the identity of wild-found hair fibres.

Finding thylacine hair wouldn’t necessarily mean the animals are out there right now. “The research can help confirm the identity of the fibre but there still needs to be an evaluation of the origin of the fibre,” Rehberg explains. “It may be possible for a historical thylacine hair to persist in the field for hundreds of years.”

However, finding hair might give researchers an idea of where to direct future searches, and would be a good piece of evidence to go along with video footage, tracks, or other signs of the much-sought marsupial.

“If you think about a crime scene investigation and all the effort that must be gone through to preserve evidence and prove its provenance,” Rehberg says, “you could expect the same level of scrutiny for any claim of thylacine hair.”

“At the very least, my [Tasmanian] tiger hair project adds to the growing body of knowledge available to the public and researchers alike, whether amateur or professional, especially with the generous support given by CSIRO.”