Kakapo the reason for its massive decline since the introduction of dogs, cats and mustelids (see "Conservation: Human impact"). The kakapo is the only species of flightless parrot in the world, and the only flightless bird that has a lek breeding system. Males loosely gather in an arena and compete with each other to attract females. Females listen to the males as they display, or "lek". They choose a mate based on the quality of his display; they are not pursued by the males in any overt way. No pair bond is formed; males and females meet only to mate. During
Kakapo in the nest (and no available nest to move them to) they will be hand-reared by the Kakapo Recovery team. To monitor the kakapo population continuously, each bird is equipped with a radio transmitter. Every known kakapo, barring some young chicks, has been given a name by Kakapo Recovery Programme officials, and detailed data is gathered about every individual. GPS transmitters are also being trialled to provide more detailed data about the movement of individual birds and their habitat use. The signals also provide behavioural data, letting rangers gather information about mating and nesting remotely. Every individual kakapo receives an