Europeans first encountered the tūī in 1770 at Queen Charlotte Sound on the north coast of New Zealand's South Island during Captain James Cook's first voyage to the Pacific Ocean.

[2][3] Specimens were brought back to England and an engraving of a tūī by the English naturalist Peter Brown, which he called "The New Zeland creeper", was published in 1776.

"[5] In 1782 the English ornithologist John Latham included the tūī as the "poë bee-eater" in his book A General Synopsis of Birds.

[6] No author had introduced a scientific name, but when in 1788 the German naturalist Johann Friedrich Gmelin revised and expanded Carl Linnaeus's Systema Naturae, he included the tūī with a short description, coined the binomial name Merops novaeseelandiae and cited the publications by Brown, Cook and Latham.

Populations have declined considerably since European settlement, mainly as a result of widespread habitat destruction and predation by mammalian invasive species.

[citation needed] Nonetheless, the species is considered secure and has made recoveries in some areas, particularly after removal of livestock has allowed vegetation to recover.

Tūī 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 kererū (New Zealand pigeon) in any combination.

Generally, when interspecific competition for the same food resources among New Zealand's two species of honeyeater occurs, there is a hierarchy with the tūī at the top and bellbirds subordinate.

[21] Male tūī can be extremely aggressive, chasing all other birds (large and small) from their territory with loud flapping and sounds akin to rude human speech.

[24] The powered flight of tūī 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.

Particularly popular is the New Zealand flax, whose nectar sometimes ferments, resulting in the tūī flying in a fashion that suggests that they might be drunk.

[27] Tūī are known for their noisy, unusual, sometimes soulful calls, different for each individual, that combine bellbird-like notes with clicks, cackles, timber-like creaks and groans, and wheezing sounds.

Songbirds or passerines like tūī have nine pairs of muscles giving them the ability to produce much more complex vocalisations, and they can be seen to be very physically involved with their songs.