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
The Bird Lover the lai develops somewhat differently: instead of a happy ending, the lai ends in tragedy. A "sophisticated rationalization" of the type is found in Chrétien de Troyes's "Lancelot, the Knight of the Cart", where Lancelot appears at Guinevere's heavily barred window and cuts his fingers bending the bars back. In French scholarship, this type is often referred to as ""loiseau bleu"" or "the blue bird", so named for a story by Madame d'Aulnoy. The Bird Lover The Bird Lover, also known as The Prince as Bird, is a type of narrative structure in folklore, no. 432 in the Aarne–Thompson classification