Australia has some unique wildlife, and despite the best efforts of cats, foxes, pigs and other introduced nasties to diminish it, it remains one of the great features of this nation. Anybody who goes camping — often even near to major centres of population — will interface with local facets of it. Whether it be goannas, snakes, kangaroos, emus, dingoes, koalas, birds, possums or all manner of critters, it’s there to be enjoyed.
However, there are some significant holes in the range of creatures which we can experience, including a few that were not incidental to our modern way of life — these were determined, planned and purposely pursued extinctions. One of the most notable of these has been the thylacine.
Also known as the Tasmanian tiger, this was one of the few carnivorous marsupials which made its way to the arrival of European settlement of Australia. There was a time when thylacines were pretty widely spread throughout Australia and New Guinea. The most recent fossilised specimen of a thylacine from the mainland has been dated at 3000 years of age.
Thylacines were very close in appearance and biology to that of the modern wolf, though they were from different evolutionary backgrounds. It’s an excellent example of parallel evolution, where the demands of survival in a specific ecological niche have imposed almost the same evolutionary responses and created almost the same outcomes in terms of the creatures we see. The wolf — essentially a dog and a normal placental mammal — is larger than the thylacine because it needs to be able to effectively hunt larger prey, but it is otherwise extremely similar. In fact, the Tassie tiger’s generic name is Thylacinus, and the species name of cynocephalus means dog head.
Formally there have been no confirmed sightings of thylacines on the mainland since European settlement, but even in the earliest days of European development in Tasmania, sightings were rare, as this was a very shy animal that lived what is called a crepuscular life — in other words, it was most active at twilight. At the time of the first European landings on Tasmania it is estimated the number of thylacines was only somewhere between 2000 and 3000.
It is believed that there were a range of impacts which drove the mainland population of thylacines to extinction: the introduction of the dingo, climate change and the impacts of man on individual animals and the competition for prey. However, there are records which may point to the survival until possibly the present day or, at least, recent times of two small mainland populations of the thylacines, one in the Flinders Ranges of South Australia, to the east of Lake Torrens (where there was a reward for their destruction during the 19th century), and in Victoria where a naturalist said that he could recall having examined the remains of two recently dead animals early in that same century.
This is compounded by the declared intention of an ‘acclimatisation society’ in 1868 to release ‘Tasmanian wolves’ in Victoria, though whether or not this actually took place is unknown. Nonetheless, there are hundreds of claimed sightings of thylacines on the mainland, from Western Australia, South Australia, NSW to the Gippsland area of Victoria. Many can be explained as mange infected foxes or dogs, but some are detailed and have a lot of credibility. It is widely accepted by many scientists that there are likely small numbers of thylacines still living on mainland Australia.
In Tasmania, despite the relatively small number of individuals, the thylacine was identified soon after settlement as a threat to the welfare of the farming community. The introduction of sheep to the landscape of Tasmania brought with it a whole new food source for the thylacine, and there were soon calls being made for managed culling of these animals variously referred to as tigers, wolves, Tasmanian dingoes or hyenas, with parliamentary pressure being brought to bear in the 1880s. This came at the same time as opinions that the steady rate of killings of individual animals by farmers would assuredly lead to extinction anyway. In 1886 the Spring Bay Tiger and Eagle Extermination Association presented a petition to parliament calling for a bounty on skins of thylacines. At the time the Tasmanian Minister for Lands said the thylacine “had not one redeeming feature.”
The bounty scheme finally became law in 1888. The commonest form of evidence taken to local police to claim the one-pound reward was that of the head.
By the 1920s thylacines had become scarce and rarely seen. The bounty scheme was terminated in 1914, but by then the damage had been done. The last known kill of a thylacine in Tasmania was in 1930, when one was caught killing poultry.
In the late 1930s impassioned appeals began to appear to preserve the ‘tiger’. In August 1936, rather belatedly, the Tasmanian tiger, was given protected status, yet just two months later, on 7 September 1936, Benjamin, the last living thylacine in captivity, died of exposure in the Beaumaris Zoo in Hobart. Suddenly, where only a few years before men had set out with guns and snares to capture and kill these animals, there were now expeditions going forth to simply find out if they still existed.
Reported thylacine sightings have continued from Tasmania since the 1930s, mostly from the more remote areas of the west coast. There have been numerous well set up scientific expeditions, using remote cameras, baiting, traps and other tactics but these have all drawn blanks. Yet the reports continue to come in, from campers, farmers and park rangers.
Regardless of the chances of discovering a cryptic (hidden) population of thylacines, either on the mainland or in Tasmania, in recent decades there has been a push for the possibilities of re-establishing the creature through its DNA. DNA is the coded building blocks of all creatures, and it was soon discovered that a complete sequence of the tiger’s mitochondrial DNA (inherited from the mother) could be recovered from the hair of dead skin specimens. Nucleic DNA, the necessary component of any cloning exercise, rapidly breaks down after about five years, making all attempts so far to retrieve a complete sequence as a failure, but rapid developments in this field are being made.
The next step would require a donor egg from a closely related organism, such as a Tasmanian devil or a tiger quoll. The likelihood of a successful cloning exercise, such as took place with the famous Dolly the sheep, are still well in the future, but a team of researchers continues to work towards recreating the “animal of not one redeeming feature.”