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 has a very small gizzard compared to other birds of their size. It is entirely herbivorous, eating native plants, seeds, fruits, pollen and even the sapwood of trees. A study in 1984 identified 25 plant species as kakapo food. It is particularly fond of the fruit of the rimu tree, and will feed on it exclusively during seasons when it is abundant. The kakapo strips out the nutritious parts of the plant out with its beak, leaving a ball of indigestible fibre. These little clumps of plant fibres are a distinctive sign of the presence of the bird. The