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Range DescriptionCyanoramphus forbesi is restricted to Little Mangere and Mangere Islands in the Chatham Island group, New Zealand. By 1930, it was extinct on Mangere Island, but by 1973 it had recolonised and numbered 40 birds and a small number of hybrids with C. n. chathamensis (of which there were 12 on the island) (Higgins 1999). In 1996, two estimates indicated that the population on Mangere Island numbered 50-120 pure-bred birds. The Little Mangere Island population is poorly known due to few visits taking place (H. Aikman in litt. 1999). In 1999, the total population was estimated to be about 120 birds (Aikman et al. 2001), but surveys in 2003 estimated 900 individuals on Mangere Island (Aikman and Miskelly 2004, D. Houston and C. Miskelly in litt. 2008). A recent study estimated that over 50% of the parakeet population on Mangere Island consisted of hybrid individuals (Chan et al. 2006), but this is expected to decrease owing to positive assortative mating (T. Greene in litt. 2012); the number of non-forbesi phenotypes is approaching the 10% management threshold (D. Houston in litt. 2012) (i.e. the number above which culling may be resumed as a management tool). Birds have been recorded visiting the south of Chatham Island, Pitt Island and Rangatira Island (Taylor 1998, D. Houston and C. Miskelly in litt. 2008, T. Greene in litt. 2012).