Also known as wax-eye or white-eye, Zosterops lateralis belongs to the widespread family Zosteropidae. New Zealand possesses one species which is a relatively recent arrival in this country from Australia. Permanent invasion occurred in or before 1856, the birds obviously being carried in flocks across the Tasman Sea by one or more of the weather systems which, in these latitudes, travel in a predominantly east-west direction. By 1861 the species had established a permanent footing in the Chatham Islands. Now it has a wide distribution throughout the country and has even reached as far north as the Kermadecs and as far south as Campbell Island. It may be found in a variety of habitats from sea level to above the tree line but it is not abundant in deep forest. Flocks form in late autumn and winter and in some years these become very common in the lowlands.
Slightly smaller than the introduced house sparrow, the silvereye is olive-green above, pale chestnut below, and there is the characteristic, almost complete, ring of white feathers around the eye. Males are slightly brighter in plumage than females.
The song is a pleasant rapid warbling which has some resemblance to that of the skylark, though it is less powerful and sustained and not given while soaring. At other times a quiet twittering may be heard.
Food may be insects, nectar, or fruit. After their arrival in New Zealand in 1856, silvereyes soon became popular because of their attack on the orchard pest woolly aphis. This earned them an alternative name of “blight bird”. But they also destroy orchard fruits and buds. When feeding on nectar they pollinate many useful trees and shrubs.
Breeding occurs mainly between September and December and at least two broods may be raised during this time. The nest is a delicate cup-shaped structure made of grass, moss, and hair, and is slung like a hammock between branches at no great height from the ground. The eggs are pale blue and the average clutch size is three.
by Gordon Roy Williams, B.SC.(HONS.)(SYDNEY), Lecturer in Agricultural Zoology, Lincoln Agricultural College.