The tiger quoll is found in eastern Australia where more than 600 mm of rain falls per year. Historically, the quoll was present throughout southeastern Queensland, through eastern New South Wales, Victoria, southeastern South Australia, and Tasmania. European settlement has severely impacted and fragmented the quoll's mainland distribution. Tiger quolls are rare in southeastern Queensland and mainly restricted to national parks. In Victoria, quoll populations have declined by nearly 50%. The range decline was not as severe in New South Wales, but they are still rare. The quoll was probably never very numerous in South Australia.