The date 7 September 1936 is widely regarded as the day when the world’s last remaining Tasmanian tiger – also known as the thylacine – took its final breath in a zoo in Hobart.
But how long did the last few dog-like striped carnivorous marsupials stick around out of sight in Tasmania’s wilderness? A few years? A couple of decades?
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According to a new analysis of 1,237 observations and claimed sightings of the animal since 1910, the thylacine may have hung on into the late 1980s and possibly even longer.
If that analysis is right it suggests that – had it had the ability or inclination – the thylacine was around long enough to catch early episodes of TV show Neighbours (c 1985), rather than existing only in the grainy black and white world of the early 20th century.
Published in peer-reviewed journal Science of the Total Environment, the research took all the observations and gave them a quality score, from reliable records backed by a physical specimen – alive or dead – to sightings by experienced bushmen or fleeting glimpses from untrained eyes.
Prof Barry Brook, of the University of Tasmania and lead author of the study, has been working for five years trying to determine the timing of the thylacine’s extinction.
“It’s one of the most iconic Australian species to go extinct,” he said.
He said just looking at records of confirmed kills, captures or sightings by past hunters or wildlife professionals suggested a likely extinction date between the 1940s and 1970s.
But he said rather than throw out later observations, the study had included them in their modelling while heavily downgrading their likelihood of being genuine.
Using this approach on observations and sightings up to 2019, this pushed the extinction date to the late 1980s to the early 2000s.
Brook says there remained regular credible sightings into the 1960s. But as the years wore on, there was a “natural attrition” of people who had been around long enough to have ever seen one.
“But if you’re talking about people who knew wildlife, then there are still occasional credible sightings in the the 1980s,” Brook said, pointing to the experience of park ranger Hans Naarding who in 1982 told bosses he had stood for several minutes with his torchlight fixed on a thylacine.
Brook said the 1936 death of a thylacine at a Hobart zoo remains the last confirmed observation with photographic evidence.
The International Union for Conservation of Nature officially declared the thylacine extinct in 1982, after numerous attempts over decades to find them failed.
As well as offering a new perspective on when the last thylacines may have died, the study also analysed the locations of observations.
Brook said based on the new research, the most likely place for the last thylacines was “somewhere in the middle of the north-west of Tasmania” around Waratah.
He said the work had also offered a method to help conservationists look for other species that are feared extinct.
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“This pattern of contraction and range decline is very typical before extinction so understanding that better can be really helpful in knowing where to look.”
While a small group of enthusiasts cling to the idea the thylacine is still around, Brook says there is “less than a 1%” chance of the animal still eking out an existence somewhere.
“It’s very hard with observational science to completely rule anything out,” he said.
Dr Stephen Sleightholme, a co-author of the research from the International Thylacine Specimen Database, said the thylacine had “captivated the public’s imagination for decades and inspired many efforts to prove its ongoing existence”.
“Our study shows that there is still much to learn about its history and ecology.”
Prof Andrew Pask, of the University of Melbourne, is part of a team trying to work out ways to resurrect the thylacine using DNA from the animal, supported by genetic samples from its relative the numbat.
Pask – who was not involved in the new study – said the research “relies on a lot of maybes”.
He said because thylacines resembled a dog, he thinks many people who were convinced they had seen one may have just been seeing modern canines.
He said: “It would have made sense that a few animals were probably still around in the world [after the 1936 death], but I think it’s very unlikely thylacines would have survived beyond a few generations. And we think each generation as about eight years.
“It’s become like our Loch Ness Monster or big foot – an almost mythical creature – but I like [that some people still think they see them] because it keeps the memory of them alive and reminds people of this amazing animal that we hunted to extinction.”