The Strangerest: The Thylacine or 'Tasmanian Tiger'

The Thylacine (binomial name: Thylacinus cynocephalus; Greek for "dog-headed pouched one") was the largest known carnivorous marsupial of modern times. It is commonly known as the Tasmanian Tiger (because of its striped back), the Tasmanian Wolf, and colloquially the Tassie (or Tazzy) Tiger or simply the Tiger.

Native to continental Australia, Tasmania and New Guinea, it is thought to have become extinct in the 20th century. It was the last extant member of its genus, Thylacinus, although several related species have been found in the fossil record dating back to the early Miocene.

The Thylacine had largely become extremely rare or extinct on the Australian mainland before European settlement of the continent, but it survived on the island state of Tasmania along with several other endemic species, including the Tasmanian Devil.

Intensive hunting encouraged by bounties is generally blamed for its extinction, but other contributory factors may have been disease, the introduction of dogs, and human encroachment into its habitat. Despite its official classification as extinct, sightings are still reported, though none proven.

Like the tigers and wolves of the Northern Hemisphere, from which it obtained two of its common names, the Thylacine was an apex predator. As a marsupial, it was not closely related to these placental mammals, but because of convergent evolution it displayed the same general form and adaptations. Its closest living relative is thought to be either the Tasmanian Devil or Numbat.

The Thylacine was one of only two marsupials to have a pouch in both sexes (the other being the Water Opossum). The male Thylacine had a pouch that acted as a protective sheath, protecting the male's external reproductive organs while running through thick brush.

Extinction in Tasmania

Although the Thylacine had been close to extinction on mainland Australia by the time of European settlement, and went extinct some time in the nineteenth century, it survived into the 1930s on the island state of Tasmania. At the time of the first settlement, the heaviest distributions were in the northeast, northwest and north-midland regions of the state.

They were rarely sighted during this time but slowly began to be credited with numerous attacks on sheep. This led to the establishment of bounty schemes in an attempt to control their numbers. The Van Diemen's Land Company introduced bounties on the Thylacine from as early as 1830, and between 1888 and 1909 the Tasmanian government paid £1 per head for dead adult Thylacines and ten shillings for pups. In all they paid out 2,184 bounties, but it is thought that many more Thylacines were killed than were claimed for.

Its extinction is popularly attributed to these relentless efforts by farmers and bounty hunters. However, it is likely that multiple factors led to its decline and eventual extinction, including competition with wild dogs introduced by European settlers, erosion of its habitat, the concurrent extinction of prey species, and a distemper-like disease that also affected many captive specimens at the time.

Whatever the reason, the animal had become extremely rare in the wild by the late 1920s. Despite the fact that the Thylacine was believed by many to be responsible for attacks on sheep, several efforts were made to save the species from extinction. Records of the Wilsons Promontory management committee dating to 1908 included recommendations for Thylacines to be reintroduced to several suitable locations on the Victorian mainland.

In 1928, the Tasmanian Advisory Committee for Native Fauna had recommended a reserve to protect any remaining Thylacines, with potential sites of suitable habitat including the Arthur-Pieman area of western Tasmania.

In 1930 Wilf Batty, a farmer, killed the last known wild Thylacine in Mawbanna, in the northeast of the state. The animal, believed to have been a male, had been seen around Batty's house for several weeks.

"Benjamin" and searches

The last known Thylacine photographed at Hobart (formerly Beaumaris) Zoo in 1933. A scrotal sac is not visible in this or any other of the photos or film taken, leading to the supposition that "Benjamin" was a female, but the existence of a scrotal pouch in the Thylacine makes it impossible to be certain.

The last captive Thylacine, later referred to as "Benjamin" (although its sex has never been confirmed) was captured in 1933 and sent to the Hobart Zoo where it lived for three years. Frank Darby, who claimed to have been a keeper at Hobart Zoo, suggested "Benjamin" as having been the animal's pet name in a newspaper article of May 1968.

However, no documentation exists to suggest that it ever had a pet name, and Alison Reid (de facto curator at the zoo) and Michael Sharland (publicist for the zoo) denied that Frank Darby had ever worked at the zoo or that the name Benjamin was ever used for the animal. Darby also appears to be the source for the claim that the last Thylacine was a male; photographic evidence suggests it was female. This Thylacine died on 7 September 1936.

It is believed to have died as the result of neglect—locked out of its sheltered sleeping quarters, it was exposed to a rare occurrence of extreme Tasmanian weather: extreme heat during the day and freezing temperatures at night. This Thylacine features in the last known motion picture footage of a living specimen: 62 seconds of black-and-white footage showing it pacing backwards and forwards in its enclosure in a clip taken in 1933 by naturalist David Fleay.

National Threatened Species Day has been held annually since 1996 on 7 September in Australia, to commemorate the death of the last officially recorded Thylacine.

Although there had been a conservation movement pressing for the Thylacine's protection since 1901, driven in part by the increasing difficulty in obtaining specimens for overseas collections, political difficulties prevented any form of protection coming into force until 1936. Official protection of the species by the Tasmanian government was introduced on 10 July 1936, 59 days before the last known specimen died in captivity.

The results of subsequent searches indicated a strong possibility of the survival of the species in Tasmania into the 1960s. Searches by Dr. Eric Guiler and David Fleay in the northwest of Tasmania found footprints and scats that may have belonged to the animal, heard vocalisations matching the description of those of the Thylacine, and collected anecdotal evidence from people reported to have sighted the animal. Despite the searches, no conclusive evidence was found to point to its continued existence in the wild.

The Thylacine held the status of endangered species until 1986. International standards state that any animal for which no specimens have been recorded for 50 years is to be declared extinct. Since no definitive proof of the Thylacine's existence had been found since "Benjamin" died in 1936, it met that official criterion and was declared officially extinct by the International Union for Conservation of Nature.

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is more cautious, listing it as "possibly extinct".

Unconfirmed sightings

The Australian Rare Fauna Research Association reports having 3,800 sightings on file from mainland Australia since the 1936 extinction date, while the Mystery Animal Research Centre of Australia recorded 138 up to 1998, and the Department of Conservation and Land Management recorded 65 in Western Australia over the same period.

Independent Thylacine researchers Buck and Joan Emburg of Tasmania report 360 Tasmanian and 269 mainland post-extinction 20th century sightings, figures compiled from a number of sources. On the mainland, sightings are most frequently reported in Southern Victoria.

Some sightings have generated a large amount of publicity. In 1973, Gary and Liz Doyle shot ten seconds of 8mm film showing an unidentified animal running across a South Australia road. However, attempts to positively identify the creature as a thylacine have been impossible due to the poor quality of the film.

In 1982 a researcher with the Tasmania Parks and Wildlife Service, Hans Naarding, observed what he believed to be a Thylacine for three minutes during the night at a site near Arthur River in northwestern Tasmania. The sighting led to an extensive year-long government-funded search.

In January 1995, a Parks and Wildlife officer reported observing a Thylacine in the Pyengana region of northeastern Tasmania in the early hours of the morning. Later searches revealed no trace of the animal.

In 1997, it was reported that locals and missionaries near Mount Carstensz in Western New Guinea had sighted Thylacines. The locals had apparently known about them for many years but had not made an official report. In February 2005 Klaus Emmerichs, a German tourist, claimed to have taken digital photographs of a Thylacine he saw near the Lake St Clair National Park, but the authenticity of the photographs has not been established.

The photos were not published until April 2006, fourteen months after the sighting. The photographs, which showed only the back of the animal, were said by those who studied them to be inconclusive as evidence of the Thylacine's continued existence.

In late 2002 researchers had some success in extracting replicable DNA from the specimens. On February 15 2005, the museum announced that it was stopping the project after tests showed the DNA retrieved from the specimens had been too badly degraded to be usable. In May 2005, Professor Michael Archer, the University of New South Wales Dean of Science, announced that the project was being restarted by a group of interested universities and a research institute.

In what they describe as a world first, researchers from Australian and U.S. universities extracted a gene from a preserved specimen of the doglike marsupial, and revived it in a mouse embryo.

In 2008 researchers Andrew J. Pask and Marilyn B. Renfree from the University of Melbourne and Richard R. Behringer from the University of Texas reported that they managed to restore functionality of a gene Col2A1 enhancer obtained from 100 year-old ethanol-fixed thylacine tissues from museum collections. The research enhanced hopes to eventually restore the population of thylacines.

That same year, another group of researchers successfully sequenced the complete thylacine mitochondrial genome from 2 museum specimens. Their success suggests that it is feasible to sequence the complete thylacine nuclear genome from museum specimens, and their results were published in the journal Genome Research in 2009.

The International Thylacine Specimen Database was completed in April 2005 and is the culmination of a 4-year research project to catalog and digitally photograph all known surviving Thylacine specimen material held within museum, university and private collections.