The Eastern cougar (a.k.a. panther, mountain lion, etc.) of the U.S. may be presumed extinct, but Australia has an even more mysterious feline problem: the repeated appearance of a cougar-like predator on a continent which never had a true native cat of any kind.
Nathan Rees, now premier of New South Wales (which includes the city of Sydney), once dismissed "panther" sightings as "an urban myth." He's not so certain any more. Amidst a continuing series of sighting reports, he opined, "It is easy for all of us to dismiss these things ... but if we're actually wrong then there is an altogether different set of scenarios." One amateur researcher has compiled a database of 600 people in the region around Sydney who think they have seen such a predator.
COMMENT: This is not a new problem. Decades of sightings of either tawny or black panther-sized animals, backed up by dead and injured livestock and pawprints, indicate that, despite lack of official confirmation, there is something going on here. How an alien big cat got established in Australia is unclear, although there are uncormfirmed reports of American military units in WWII bringing them as mascots.
This seems to be a different problem from the "Queensland tiger-cat," another set of reports that indicate Australia just might still house a population of a presumed-extinct catlike marsupial predator.