Prosthemadera novaeseelandiae chathamensis

The tui (Māori: tūī; Prosthemadera novaeseelandiae) is an endemic passerine bird of New Zealand, and the only species in the genus Prosthemadera. It is one of the largest species in the diverse Australasian honeyeater family, and one of two living species of that family found in New Zealand, the other being the related New Zealand bellbird. The species has a wide distribution in the archipelago, ranging from the subtropical Kermadec Islands to the sub-Antarctic Auckland Islands, as well as the main islands. The bird's common name tui comes from the Māori language (where it is now spelled tūī). The plural is tui in modern English, or ngā tūī in Māori usage; some speakers still use the '-s' suffix to produce the Anglicised form tuis to indicate plurality, but this practice is becoming less common. Early European colonists called it the parson bird or mockingbird; however, these names are no longer used. The tui is a large honeyeater, 27 to 32 cm (11–13 in) in length. The Chatham Islands subspecies is larger on average than the nominate subspecies, and heavier. Males tend to be heavier than females. Nominate males weigh between 65–150 g (2.3–5.3 oz), and females 58–105 g (2.0–3.7 oz). Males of the Chatham subspecies are 89–240 g (3.1–8.5 oz) and females 89–170 g (3.1–6.0 oz). At first glance the bird appears completely black except for a small tuft of white feathers at its neck and a small white wing patch, causing it to resemble a parson in clerical attire. On closer inspection (see image) it can be seen that tui have brown feathers on the back and flanks, a multicoloured iridescent sheen that varies with the angle from which the light strikes them, and a dusting of small, white-shafted feathers on the back and sides of the neck that produce a lacy collar. 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 brushtail possums (which eat eggs and chicks), stoats, the common myna (which compete with tui for food and sometimes takes eggs), and rats. Tui prefer broadleaf forests below 1500 metres, but will tolerate quite small remnant patches, regrowth, exotic plantations and well-vegetated suburbs. They are one of the most common birds found in urban Wellington. 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 kererū (New Zealand wood pigeon) in any combination. Generally, when interspecific competition for the same food resources among New Zealand's three species of honeyeater occurs, there is a hierarchy with the tui at the top, then bellbirds and stitchbirds successively subordinate to the species above them—they are thus frequently chased off by tui at a food source such as a flowering flax plant. 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 favoured 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.