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Range DescriptionGallirallus australis is endemic to New Zealand. Subspecies greyi is mostly restricted to the east coast of the North Island, and experienced significant declines after the early 1980s to c.4,000 birds3,4,6. Several releases to former mainland habitats have been attempted, but most have been largely unsuccessful3 owing to high levels of predation. However, introduced populations at Russell and Kawakawa Bay, as well as the main remnant population on the east coast of the North Island between Motu and Opitiki, have all expanded and the total population size of this subspecies is now estimated at 8,000 individuals12. Nominate australis remains locally common in north and west South Island3,5, but numbers fluctuate dramatically, even in large populations3. In north-west Nelson, numbers plummeted by c.95%4, in north Westland, counts indicate declines of over 90% in c.20 years1, and declines were also noted in Fiordland. However, a number of reintroductions and predator control for the benefit of a number of threatened mainland species have led to recent increases in parts of the South Island10,12. Subspecies hectori is now extinct in its natural range, but was introduced to Chatham and Pitt Islands where it may number between 38,000-58,000 birds4, and survives a take of 5,000 birds annually3. Some individuals of this subspecies have been returned to islands on lakes in the South Island and a mainland release is anticipated12. Subspecies scotti became extinct on Stewart Island in the 1990s6, but introduced populations survive on surrounding islands5. Their total numbers are thought to be less than 8,000 and declining12. Overall, the four races are present (many as introduced populations) on more than 70, mostly tiny, offshore islands3. Whilst there have been no major declines in the last ten years, future population crashes are predicted, as climate change is likely to increase the probability of such events occurring10.