Holocene extinction may have put some pressure on other birds but at the time of early European contact (18th Century) and colonisation (19th Century) the bird life was prolific. With them, the Europeans brought ship rats, possums, cats and mustelids which decimated native bird life, some of which had adapted flightlessness and ground nesting habits and others had no defensive behavior as a result of having no extant endemic mammalian predators. The kakapo, the world's biggest parrot, which is flightless, now only exists in managed breeding sanctuaries. New Zealand's national emblem, the kiwi, is on the endangered bird list. There has been
Kakapo have a polygynous lek breeding system. It is also possibly one of the world's longest-living birds. Its anatomy typifies the tendency of bird evolution on oceanic islands, with few predators and abundant food: a generally robust physique at the expense of flight abilities, resulting in reduced wing muscles and a diminished keel on the sternum. Like many other New Zealand bird species, the kakapo was historically important to Māori, the indigenous people of New Zealand, appearing in many of their traditional legends and folklore; however it was also heavily hunted and used as a resource by Māori, both for its