Tasmanian tiger went extinct in the 1980s - not 1930s, research claims

"Many of those specimens are still protected in museums today, which gives researchers like me the opportunity to learn more about them and share that information with the public and other scientists," he added.

Three parasite species have been recorded

The flea mentioned above, a roundworm, and a tapeworm are the three parasite species identified in thylacines.

"Interestingly though, the roundworm and tapeworm were accidental infections, with the roundworms originating from a hapless pigeon which was caught and eaten by a Thylacine in the London Zoo and the tapeworm likely having been contracted by a Thylacine eating scats of a Tasmanian devil," Kwak said.

"However, the Thylacine probably had many other parasites if their relatives, the quolls, and Tasmanian devils, are any indicator. Sadly though, any chance of understanding these other mystery parasites probably vanished when the Thylacine became extinct," he explained.

Advanced gene-editing technology

Although the last known Thylacine passed away about a century ago, some scientists have begun to work on the "de-extinction" of the species. These attempts, based on cutting-edge gene-editing technology, could have a significant impact on the burrowing flea if they are successful.

"If the Thylacine were to be resurrected through de-extinction science, sooner or later conservationists would push for it to be rewilded into Tasmania so that it could once again fulfill its ecological functions," Kwak said.

"Given that the burrowing flea and its remaining hosts are already widespread in Tasmania, it would really only be a matter of time until the fleas 'rewilded' themselves back onto the Thylacine. Perhaps by 2040, Tasmania may again have the burrowing fleas and Thylacine together back in the ecosystem just as they were 200 years ago in 1840!"

The study was published in Science of The Total Environment on March 18.

Study abstract:

Like the Dodo and Passenger Pigeon before it, the predatory marsupial Thylacine (Thylacinus cynocephalus), or ‘Tasmanian tiger’, has become an iconic symbol of anthropogenic extinction. The last captive animal died in 1936, but even today reports of the Thylacine's possible ongoing survival in remote regions of Tasmania are newsworthy and capture the public's imagination. Extirpated from mainland Australia in the mid-Holocene, the island of Tasmania became the species' final stronghold. Following European settlement in the 1800s, the Thylacine was relentlessly persecuted and pushed to the margins of its range, although many sightings were reported thereafter—even well beyond the 1930s. To gain a new depth of insight into the extinction of the Thylacine, we assembled an exhaustive database of 1237 observational records from Tasmania (from 1910 onwards), quantified their uncertainty, and charted the patterns these revealed. We also developed a new method to visualize the species' 20th-century spatio-temporal dynamics, to map potential post-bounty refugia and pinpoint the most-likely location of the final persisting subpopulation. A direct reading of the high-quality records (confirmed kills and captures, in combination with sightings by past Thylacine hunters and trappers, wildlife professionals and experienced bushmen) implies a most-likely extinction date within four decades following the last capture (i.e., 1940s to 1970s). However, uncertainty modelling of the entire sighting record, where each observation is assigned a probability and the whole dataset is then subject to a sensitivity analysis, suggests that extinction might have been as recent as the late 1980s to early 2000s, with a small chance of persistence in the remote south-western wilderness areas. Beyond the intrinsically fascinating problem of reconstructing the final fate of the Thylacine, the new spatio-temporal mapping of extirpation developed herein would also be useful for conservation prioritization and search efforts for other rare taxa of uncertain status.