For those wondering how it could have survived for decades with no one finding proof, it is hard to overstate how remote and unpopulated parts of Tasmania are.

For those wondering how it could have survived for decades with no one finding proof, it is hard to overstate how remote and unpopulated parts of Tasmania are. Almost half of the island is a national park, and has almost no roads or settlements. The centre is mountainous. Some spots in the interior require covering dozens of kilometres over cliffs and dense rainforest. Many places have probably never been seen by humans, including the indigenous Tasmanians, who appear to also have kept to the same valleys and plains the colonists initially preferred. It looks like a small island against the mainland, but it's about the area of South Carolina with 600k people, giving a population density just a few times higher than Canada, and less than the continental USA.