Conservation status

The species of gerygone on Lord Howe Island (G. insu-laris) is Extinct, that on Biak (G. hypoxantha) is Endangered, and the one on Norfolk Island (G. modesta) is Vulnerable. These island forms have suffered from major habitat loss as well as from introduced mammalian predators. The yel-lowhead (Mohua ochrocephala) of New Zealand is also Vulnerable. The 2000 Action Plan for Australian Birds lists a large number of acanthizids as threatened or nearly so. The bristlebirds have suffered from habitat loss, increased fire frequency, grazing by introduced mammals, and predation by mammalian carnivores. The western subspecies of rufous bristlebird (Dasyornis broadbenti) is Extinct, both subspecies of eastern bristlebird (D. brachypterus) are Endangered, one critically, whereas the western bristlebird (D. longirostris) is regarded as Vulnerable. Only the Coorong subspecies of rufous bristlebird is currently secure. Several isolated subspecies are threatened—with brown thornbills and scrubtits (Acanthornis magnus) on King Island being Critically Endangered. The chestnut-breasted whiteface (Aphelocephala pectoralis) and speckled warbler were considered Near Threatened throughout their range. Loss and degradation of habitat by agriculture and grazing are the main causes.

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