Islands that are bereft of predators can work a special kind of evolutionary magic on their birds. Here, flapping flight serves little purpose, and bird species can evolve to lose their flying abilities entirely, gorging on food and developing pot-bellied physiques. Enter, the kakapo: the world’s only flightless parrot – and the heaviest, too.
Found only in New Zealand, the bird’s name comes from the Maori ‘kākāpō’, meaning ‘night parrot’. Among its nocturnal adaptations are special whisker-like facial feathers for feeling in the dark, a highly developed sense of smell, and a unique musky odour which helps the birds keep track of one another. In the breeding season, males regularly joust for the finest hilltops, digging out a series of bowl-shaped excavations which help to amplify their booming mating calls.
A victim of evolving in a victim-less world, the kakapo has fared badly against a volley of recently introduced predators, including cats, rats and stoats. The bird’s main defence technique – simply freezing on the spot – certainly doesn’t help its cause. Today, just 147 kakapo remain, but conservation attempts are starting to take effect: this year has been the best breeding season on record. The kakapo’s calls have rung through New Zealand’s night sky for as many as 30 million years. If we care enough, there may be fight in these old birds yet…
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