Though superficially there is a considerable resemblance between the New Zealand bird called by this name and the true robin of Britain and Europe, the two are not related. The local species belongs to the Muscicapidae or flycatchers, whereas the robin redbreast is one of the Turdidae – the same family that includes blackbirds and song-thrushes. The common name, however, is now so well established that it is fruitless to try to replace it. Scientifically the New Zealand robin is Petroica (Miro) australis and there are four races – one in the North Island, one in the South, one on Stewart Island, and one now restricted to Little Mangere Island in the Chatham group. Differences in size and colour distinguish them. With the exception of the Chatham Island robin, which is wholly black, the other races are sooty grey on head, throat, back, and wings, and whitish or yellowish on the abdomen. Females are duller and smaller than males. Head and eyes are large and the male, in particular, is extremely tame.
Robins occur in the central forested areas of the North Island and are nowhere abundant, although they appear to be maintaining their numbers. Outside of these areas they are rare or absent in the North Island, except on Little Barrier and Kapiti Islands where they are common. In the South Island they are rare in the east south of Marlborough and are absent from a considerable part of Westland. They are locally common on Stewart Island and occur on some of its off-lying islets. On Little Mangere, the Chatham Islands robin population was under 100 at the last count and is in danger of extinction.
As well as being insectivorous, robins eat worms and readily pick up scraps around camp and picnic sites. Much of their time is spent upon the ground searching for food. The breeding season is from October to February. Males defend a territory and the females build a cup-shaped nest in which they incubate two or three eggs for about 18 days.
Robin habitat is usually tall native forest, though nowadays it may sometimes include plantations of introduced pines. Manuka scrub in the vicinity of forest may also be occupied.
The clear sustained song, with its richness and variety of phrasing, is perhaps the finest possessed by any native species.
by Gordon Roy Williams, B.SC.(HONS.)(SYDNEY), Lecturer in Agricultural Zoology, Lincoln Agricultural College.