Tui known for aggressive displays
Tui, particularly the males, can be very aggressive.
They are often seen with their heads lowered and wings extended, which is a typical pose when something has caused a reaction.
Most often the aggression occurs around a food source. Tui will often chase all other birds away from a bird-feeding table and this will usually include other tui.
In addition to the wing display, they will often erect their body feathers, seemingly to appear larger and so intimidate a rival.
They have even been known to chase away magpies and harrier hawks.
Another characteristic behaviour is seen in the mating season.
They have short, powerful wings and noisily use these to perform a mating display in which they rise at speed in a vertical climb before stalling and dropping in a powerful dive.
Their songs and calls are distinctive and they can combine bell-like calls with a range of cackles and wheezing sounds.
History records that tui were trained by the Maori to use quite complex speech phrases and some folk today have similar success with tui that frequent human habitats.
It's often observed that a tui can be on a branch singing with apparent gaps in the song. The beak opens and the throat tufts vibrate, but no sound is heard.
This is because some of the wide range of tui sounds are beyond the human register. We just can't hear them.
It's interesting to note that they sometimes sing at night, especially during a full moon.
The Southland Times