The Tui (Prosthemadera novaeseelandiae), is an endemic passerine bird of New Zealand. It is one of the largest members of the diverse honeyeater family. Tui are found through much of New Zealand, particularly the North Island, the west and south coasts of the South Island, Stewart Island/Rakiura and the Chatham Islands where an endangered sub-species particular to these islands exists. Other populations live on Raoul Island in the Kermadecs, and in the Auckland Islands (where, with the New Zealand Bellbird, it is the most southerly species of honeyeater).
Populations have declined considerably since European settlement, mainly as a result of widespread habitat destruction and predation by mammalian invasive species. Nonetheless, the species is considered secure and has made recoveries in some areas, particularly after removal of livestock has allowed vegetation to recover. Predation by introduced species remains a threat, particularly stoats, the Common Myna (which competes with Tui for food and sometimes takes eggs), and rats.
Tui are considered to be very intelligent, much like parrots. They also resemble parrots in their ability to clearly imitate human speech, and are known for their noisy, unusual call, different for each individual, that combine bellbird-like notes with clicks, cackles, timber-like creaks and groans, and wheezing sounds””the unusual possession of two voice boxes enable Tui to perform such a myriad of vocalizations. Some of the huge range of Tui sounds are beyond the human register. Watching a Tui sing, one can observe gaps in the sound when the beak is agape and throat tufts throbbing. Tui will also sing at night, especially around the full moon period.
Nectar is the normal diet but fruit and insects are frequently eaten, and pollen and seeds more occasionally. Particularly popular is the New Zealand flax , whose nectar sometimes ferments, resulting in the Tui flying in a fashion that suggests that they might be drunk. Tui are the main pollinators of flax, kowhai, kaka beak and some other plants.
Male Tui can be extremely aggressive, chasing all other birds (large and small) from their territory with loud flapping and sounds akin to rude human speech. This is especially true of other Tui when possession of a favored feeding tree is impinged. Birds will often erect their body feathers in order to appear larger in an attempt to intimidate a rival. They have even been known to mob harriers and magpies. The powered flight of Tui is quite loud as they have developed short wide wings, giving excellent maneuverability in the dense forest they prefer, but requiring rapid flapping. They can be seen to perform a mating display of rising at speed in a vertical climb in clear air, before stalling and dropping into a powered dive, then repeating. Much of this behavior is more notable during the breeding season of early spring””September and October. Females alone build nests of twigs, grasses and mosses.
Tui prefer broadleaf forests below one mile but will tolerate quite small remnant patches, re-growth, exotic plantations and well-vegetated suburbs. They are usually seen singly, in pairs, or in small family groups, but will congregate in large numbers at suitable food sources, often in company with Silvereyes, Bellbirds, or Kereru.