This is a New Zealand member of the flycatcher family, subfamily Muscicapinae, to which also belong the native robin and fantail. In spite of the common name and some resemblance in appearance and habits to the tits or titmice of Britain and Europe, the two are not related; the name, although well established, is therefore misleading. Maori names were miromiro (North Island) and ngiru-ngiru (South Island); scientifically the species is Petroica macrocephala.
There are five subspecies. One occurs on the North Island and its off-lying islets, one on South Island and Stewart Island and their off-lying islets, one on the Chathams, one on the Snares, and one on the Auckland Islands. Minor differences in colour and size separate the races, with the exception of the Snares Island bird which is wholly black. The others are, in general, dark above with a white wing bar and pale on breast and belly. North Island birds have white underparts; those of the South, Stewart, Chathams, and Aucklands are yellowish below. The upper plumage of males is black; that of females is brown and, in general, duller throughout than that of males. The Auckland Islands females are exceptions in that their plumage closely resembles that of the males.
Tomtits are sometimes confused with the native robins to which they are closely related, but they are much smaller, have a larger and more obvious area of white or cream on their underparts, carry a white wing bar (less conspicuous in the female), have not so upright a stance as the robins, usually hold their wings drooped, and are more active and spend much less time on the ground. Habitat is primarily beech forest, though they may also be found on the edges of clearings in scrub and in plantations of introduced pines. In winter, orchards and gardens may also be inhabited.
Tomtits are insectivorous. Breeding occurs from August to January, with the peak about November. The males set up and defend territories and the females make nests of moss, fine twigs, and straws bound together with cobwebs. There is a tendency to place these in hollows or cavities fairly close to ground level. During the incubation of the three to five eggs, the females are fed by the males. Two broods may be raised in a season.
The common call is a high-pitched “see see see”; there is also a song which is heard during the breeding season. This is a short repetitive trill, sounding a little like a fragment of the song of the grey warbler, and it has been rendered as “ti, ti, ti, oly, oly, oly, ho”.
by Gordon Roy Williams, B.SC.(HONS.)(SYDNEY), Lecturer in Agricultural Zoology, Lincoln Agricultural College.