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 nests are intensively managed. Before Polynesian rats were removed from Whenua Hou, they were a threat to the survival of young kakapo. Of 21 chicks that hatched between 1981 and 1994, nine were either killed by rats or died and were subsequently eaten by rats. Nest protection was intensified after 1995 by using traps and poison stations as soon as a nest was detected. A small video camera and infra-red light source would watch the nest continuously, and scare approaching rats with flashing lights and loud popping sounds. All kakapo islands are now rat-free, but infrared cameras still allow rangers