Kakapo and stiffness required for flight, they are exceptionally soft, giving rise to the specific epithet "habroptilus". The kakapo has a conspicuous facial disc of fine feathers resembling the face of an owl; thus, early European settlers called it the "owl parrot". The beak is surrounded by delicate feathers which resemble vibrissae or "whiskers"; it is possible kakapo use these to sense the ground as they walk with its head lowered, but there is no evidence for this. The mandible is variable in colour, mostly ivory, with the upper part often bluish-grey. The eyes are dark brown. Kakapo feet are large,
Kakapo kakapo is believed to employ bacteria in the fore-gut to ferment and help digest plant matter. Kakapo diet changes according to the season. The plants eaten most frequently during the year include some species of "Lycopodium ramulosum", "Lycopodium fastigium", "Schizaea fistulosa", "Blechnum minus", "Blechnum procerum", "Cyathodes juniperina", "Dracophyllum longifolium", "Olearia colensoi" and "Thelymitra venosa". Individual plants of the same species are often treated differently. Kakapo leave conspicuous evidence of their feeding activities, over feeding areas that range between and per individual. Kakapo feeding grounds almost always host manuka and yellow silver pine ("Lepidothamnus intermedius") scrubs. Fossil records indicate that in