Kākāpō don’t breed every year – that depends on whether there’s enough rimu fruit around for them to eat. But when they do breed, they do it different to most! Find out about the kākāpō’s unique courtship!
The kākāpō ‘boom’ and ‘ching’
In the breeding season, the male kākāpō can inflate like a balloon and emit a low ‘sonic’ boom which, in mountainous terrain, can be heard up to five kilometres away.
Listen to the Kākāpō Boom
Breeding activity usually starts in about December, when male kākāpō take to prominent ridges, rocks or hilltops with low-growing vegetation and begin a courtship competition for female attention. This is known as ‘lek’ breeding, and is not known from any other parrot species in the world – or from any other New Zealand bird.
From its prominent bowl site, each bird inflates a thoracic air sac and emits a deep resonant non-directional ‘boom’ from its swollen body, announcing to any females in the area that he is ready to mate. After 20-30 booms they then make a high-pitched metallic call, or ‘ching’.
Listen to the Kākāpō Ching
This pinpoints the male’s position, to direct the females to him. The booming and chinging serenade can last for eight hours without break, every night for 2-3 months in the breeding seasons when nesting occurs.
The males compete against each other, and can release thousands of ‘booms’ a night.
Each male also forms a network of tracks radiating from a bowl-like depression in the earth, from which it is based. This is known as a ‘track and bowl’ system, which is also unique among parrot species of the world.
Females will travel long distances in order to mate with her preferred male or males, often walking past others in the process. We don’t know what qualities in a male make him more attractive but some are clear favourites and will attract many of the females while other males are not selected at all.
Female kākāpō will often mate more than once with her chosen male, or even with multiple males.
The female kākāpō lays between one and four eggs (slightly smaller than a chicken egg), which hatch after about 30 days. Nests are usually located in good shelters such as hollow trees or caves made by rocks and roots.
Male kākāpō have no involvement in incubating eggs or chick rearing. As a solo parent, the female has to leave the nest at night in search of food, leaving the eggs or chicks alone. The chicks will typically fledge, or leave the nest, after about ten weeks. However, the mother may keep feeding the chicks for up to six months.