Two different "Dromaius" species were present in Australia at the time of European settlement, and one additional species is known from fossil remains. The insular dwarf emus, "D. n. baudinianus" and "D. n. minor", originally present on Kangaroo Island and King Island respectively, both became extinct shortly after the arrival of Europeans. "D. n. diemenensis", another insular dwarf emu from Tasmania, became extinct around 1865. The mainland subspecies, "D. n. novaehollandiae", remains common. The population of these birds varies from decade to decade, largely being dependent on rainfall; in 2009, it was estimated that there were between 630,000 and 725,000 birds. Emus were introduced to Maria Island off Tasmania, and Kangaroo Island off the coast of South Australia, during the 20th century. The Maria Island population died out in the mid-1990s. The Kangaroo Island birds have successfully established a breeding population.