On September 7, 1936, the last known Tasmanian tiger, or thylacine, named Benjamin, died in captivity.
We were reminded of that in late May of this year, when long-lost footage of this animal at the Hobart Zoo was found. It was shot in 1935, making it the last known moving footage of a Tasmanian tiger, and footage of the last known individual of the species at that.
This is the last living Tasmanian tiger:
Though the Tasmanian tiger disappeared from the Australian mainland around 3,000 years ago, it continued to do well on the island of Tasmania. That is, until it was hunted to extinction:
The establishment of the first colonies in Tasmania in the early 1800s ... brought the farming industry. Settlers cleared large areas of land and cultivated livestock such as sheep and cattle.
Despite evidence that feral dogs and widespread mismanagement were responsible for the majority of stock losses, the thylacine became an easy scapegoat and was hated and feared by the Tasmanian public.
As early as 1830 bounty systems for the thylacine had been established, with farm owners pooling money to pay for skins. In 1888 the Tasmanian Government also introduced a bounty of £1 per full-grown animal and 10 shillings per juvenile animal destroyed. The program extended until 1909 and resulted in the awarding of more than 2180 bounties.
Hunter poses with dead thylacine, 1869 (Tasmanian Museum and Art Gallery)
People in Tasmania and other areas of Australia want to believe that the Tasmanian tiger still roams in the wild, much like people in the U.S. want to believe in Sasquatch. Tasmania even alludes to this on its license plate:
There are societies dedicated to finding the animal in the wild, but they’ve never been able to produce any conclusive evidence of it. Just a number of verbal accounts, grainy footage, and all the usual stuff.
No, the Tasmanian tiger is gone forever, and humans are responsible.
But as we found out in a Monash University (Australia) study published Wednesday, August 19 in Proceedings of the Royal Society B, the rationale for humans eradicating the Tasmanian tiger — the fear that they were attacking sheep — was erroneous.
The Tasmanian tiger was innocent.
Remarkably, the body weight of the Tasmanian tiger had never been conclusively established. Up to now, it had been assumed to be somewhere around 30 kg, but this was based on old anecdotal evidence. So these Monash researchers analyzed 93 specimens from around the world — skeletons, mounted specimens, and even the only wet specimen (in alcohol) in the world. They reconstructed a 3-D model of the animal and found out that the average weight of the Tasmanian tiger was actually much less, only about 16.7 kg.
It had already been suspected that the jaw structure of the thylacine was too weak to attack larger prey like sheep and that it seemed far better geared toward going after smaller creatures like wallabies, bandicoots, and possums.
But the new body-weight data is very compelling. There is a correlation between the body masses of predator and prey which establishes that in order to regularly attack large prey like sheep, a predator typically needs to exceed an average body mass of about 21 kg, to the right of the gray strip:
C. latrans = coyote, C. lupus = wolf/dingo
You may notice Canis latrans represented within the same gray strip that the Tasmanian tiger resides within. That is the coyote, and the reality is that coyotes, by and large, do not kill sheep. Their jaw structure is strong enough to do it, but they aren’t large enough to be obligated to take down animals of that size in order to survive. Being a little smaller, they’re agile enough to grab bunnies and squirrels and the like, and they can derive plenty of nutrition to keep going that way.
Canis lupus, the wolf/dingo, known to attack larger prey like sheep, is also labeled on the graph. It has an average body weight of 40 kg, well above the threshold.
The Monash researchers conclude in a piece they wrote for The Conversation to accompany their study:
The thylacine was much smaller than previously thought, and this aligns with the smaller prey size suggested by the earlier studies. Predators below 21 kg – in which we should now include the thylacine – all tend to hunt prey smaller than half their size. The “Tasmanian wolf” probably wasn’t such a danger to Tasmanian farmers’ sheep after all.
By rewriting this fundamental aspect of their biology, we are closer to understanding the role of the thylacine in the ecosystem – and to seeing exactly what was lost when we deliberately hunted it to extinction.
Another scapegoat, another conspiracy theory, another irreparable loss. Will we ever learn?
Two of the five Tasmanian tiger carcasses that survive in museums
A thylacine pup preserved in alcohol since it died in 1909
