The Piopio, or New Zealand Thrush, may have been two species rather than one. Two quite distinct kinds existed, and they are usually regarded as races of the same species:
nominate capensis of the South Island; and race tanagra of the North Island. There are good reasons for supposing that they should be treated as separate species. First, the plumages are very different. Second, the structure of the beak is not quite the same, being considerbly heavier and stouter in North Island birds. Third, each had a clearly definable and isolated geographical range, so they had no scope for interbreeding. It is perhaps the extreme rarity of specimens from the North Island that has prevented this idea from being investigated further. A third suggested race, minor, identified from specimens taken from tiny Stephens Island, a short distance offshore from the South Island in the Cook Straits, is only doubtfully distinct from the South Island form.
Just as the question of species is somewhat doubtful, so too is the bird’s place in any systematic list. There is no general agreement as to where this creature’s relationships lie and it has been associated with various passerine groups. Certainly it is not a thrush. This term was used simply as a comforter for early settlers in New Zealand who were anxious to see in the new land anything that could remind them of their old homes. Thus, there are New Zealand robins, New Zealand crows, New Zealand wrens and New Zealand thrushes, none of which have any real connection with the species that inhabited the “old” country, but which simply bore a vague, superficial resemblance to them. Systematists have aligned the Piopio (a Maori word that is derived from the bird’s call) with the whistlers and the bowerbirds. The bowerbird hypothesis is, perhaps, the more likely, but the Piopio could easily belong close to another group altogether.
In the early days of European settlement Piopios were common birds, at least on South Island. The species was able to occupy many differing types of environment from sea-level up to the higher alpine country; the preference was for wooded country close to water. Its fate was almost certainly sealed by the fact that it was so tame and confiding. Individuals would hop around doors and windows in the hope of picking up scraps of food, or drop unwarily onto the forest floor. This left them horribly vulnerable to the attacks of dogs and cats, and the species steadily succumbed. Although much later dates are sometimes given, it seems that the last reliable record of the North Island Piopio comes from the year 1902. A few South Island birds survived for rather longer but by the early years of the twentieth century this form too was realistically finished. The most recent record which has any claim to credibility comes from Lake Hauroko in 1949.
Piopios lived on a fairly wide variety of different kinds of food. They would eat insects, worms, fruit, buds, seeds, leaves and any kitchen scraps that they could get hold of. A cup-shaped nest was built in the trees from twigs and mosses, with a lining of soft grasses or down. Two white eggs, spotted and blotched with brown, were laid in December. The musicality of the species was mentioned by Buller (1887-88). Describing a captive individual, he wrote:
It was when I obtained a caged Piopio that I first became acquainted with its superior vocal powers…He often astonished me with the power and variety of his notes. Commencing sometimes with the loud strains of the Thrush, he would suddenly change his song to a low flute-note of exquisite sweetness; and then abruptly stopping, would give vent to a loud rasping cry, as if mimicking a pair of Australian Magpies confined in the same aviary. During the early morning he emitted at intervals a short flute-note, and when alarmed or startled uttered a sharp repeated whistle.
Mus. Carlsonianum 2: 45.