A Layman's Guide to the Tasmanian Tiger Range and Habitat

Though indirectly, the limited geographical range and natural habitat of the Tasmanian tiger, aka thylacine, had a crucial role to play in its extinction.
The thylacine, also referred to as the Tasmanian tiger or the Tasmanian wolf, was the largest carnivorous member of the marsupial family, which was found in abundance in Australia and New Guinea around 2000 years ago. It became extinct in the 20th century, probably due to human encroachment in its natural habitat. As its population in the wild started dwindling long ago, it's a little difficult to ascertain its geographical range. Thus, one has to take into account its behavior and undertake a study of the fossils that support the claims of its existence to find out more about its range.
Tasmanian Tiger
The Tasmanian tiger was a carnivorous marsupial, which was predominantly characterized by its canid-like appearance. At full-growth, it could attain a length of around 5 - 6 feet from its mouth to tail, and weigh up to 65 lbs. It sported a light brown fur coat, with black stripes running down from the shoulders to the base of its tail. It had a relatively large skull compared to its body. Its specially designed jaw allowed it open its mouth as wide as 120 degrees.
Predominantly a nocturnal creature (i.e., active during the night), the Tasmanian tiger also displayed crepuscular behavior (i.e., active during the dusk and dawn) at times. It had a strong sense of smell, which it used effectively while hunting in the dark. Thylacines were solitary hunters, which preyed on a range of smaller animals, including wallabies, rabbits, and ground-dwelling birds.
Geographical Range and Habitat
Fossil records and aboriginal art suggest that the Tasmanian tiger was found all over the Australian mainland, and some parts of New Guinea, around 2000 - 3000 years ago. It was the apex predator, which fed on a range of grazing mammals and thus, preferred open forests and scrublands, which were preferred by its prey. Inhabiting the regions closer to the dense forests ensured that it could take shelter in case of any threat, mainly from humans. Other than these open grasslands, the thylacine also preferred wetlands and eucalyptus forests. It would take shelter in hollow logs, dense forests, or rock outcroppings in the hilly areas in the vicinity.
As human intervention in its natural habitat and competition with dingoes increased, it was forced to take shelter in isolated areas. By the beginning of the 20th century, thylacine population was restricted to the island of Tasmania. Lack of conservation measures resulted in further decline in their population, and it eventually became extinct. The last Tasmanian tiger in captivity died at Hobart Zoo on September 7, 1936. Even though a few sightings have been reported over the last few years, none of these have been confirmed.
The Tasmanian tiger was declared extinct by the International Union for Conservation of Nature (IUCN) in 1986. Along with habitat destruction due to human encroachment and competition with other species, the delay in implementation of conservation measures was also responsible for the extinction of this species. The authorities, however, didn't learn any lesson from this mistake, and within a century of its extinction, its closest relative, the Tasmanian devil was brought to the verge of extinction.