A New Zealand forest filled with birds is alive with sounds, as birds find food, defend their territory, attract mates and guard chicks. Some small forest birds are easier to track by ear than by eye.
Today, many forests have fallen quiet as introduced predators take their toll. The best places to hear the hubbub are predator-free areas – offshore islands, and fenced or managed ‘island’ reserves on the mainland.
It is illegal for people to hunt any native forest birds.
Nearly all of New Zealand’s small native forest birds are endemic – found nowhere else. Many belong to families that only exist in New Zealand, and have unusual characteristics such as very strong legs and limited flight. Only the silvereye and shining cuckoo are not endemic.
Most of the small forest birds are passerines – belonging to the order Passeriformes. Sometimes called perching birds, they have four toes (three pointing forwards and one backwards) with which they cling to branches. Passerines are the largest bird group worldwide, and probably originated on the Gondwana supercontinent.
New Zealand began to drift away from Gondwana around 85 million years ago. At least one passerine family has probably evolved in isolation ever since – Acanthisittidae, the New Zealand wrens (not related to northern hemisphere wrens). Surviving members are the tiny rifleman and the rock wren.
Another ancient passerine family is Callaeidae, the New Zealand wattlebirds, which are unrelated to Australian wattlebirds. Its members are the saddlebacks, the kōkako (larger birds) and the extinct huia. The stitchbird is thought to be related to this group, in a family of its own. A third endemic passerine family is Mohouidae, which includes the yellowhead, whitehead and brown creeper.
Other small forest species have ancestors that arrived later, across the sea from Australia. Some came via islands in the north Tasman Sea, probably when more of the Norfolk Ridge was above water. Later arrivals include the ancestors of parakeets, honeyeaters (bellbirds and tūī), warblers, robins and tomtits. The silvereye is a more recent immigrant – it is also found in Australia.
New Zealand forests also have two species of migratory cuckoos.
Most of the small forest birds have a possible life span of 12 to 15 years, but in a typical forest with predators, their life expectancy is about three years.
New Zealand’s smallest bird is the rifleman or tītiti pounamu (Acanthisitta chloris). It belongs to an ancient endemic family of Gondwanan origin, Acanthisittidae (New Zealand wrens) in the Passeriformes (perching birds) order. This family of just two surviving species – the rifleman and rock wren – is a separate group from all other 5,000 birds in that order.
The rifleman’s English, Māori and scientific names all refer to the male’s green plumage: New Zealand Infantry riflemen wore green coats, pounamu is the Māori word for greenstone, and chloris is Greek for yellowish green.
The male’s back plumage is green, and the female’s is flecked brown. Just 8 centimetres long, they have no tail to speak of, and their tiny body is almost round. The male weighs 6 grams, the female 7 grams – one-third of the weight of a house mouse. The rifleman’s delicate thorn-like bill is slightly upturned, and its fine black legs end in oversized toes (three pointing forward and one back, like other passerines).
Riflemen move around the forest in short aerial hops, clinging easily to rough tree trunks. Working their way up a tree, they take spiders, beetles, small wētā, caterpillars and moths from foliage and cracks in the bark. Adults and young often forage close together. They keep in contact with a high-pitched buzzing call, a single note that is out of hearing range for some people. Each pair has its own territory, which both males and females defend.
The rifleman and the alpine rock wren are the only remaining species of the ancient New Zealand wren family. Five other species – four of them flightless – were made extinct by introduced predators. Feral cats had wiped out the last Stephens Island wren by 1894. The most recent loss was the bush wren. Once widespread, its gradual disappearance went almost unnoticed. It was last seen around 1972.
The male builds nests in tree or rock hollows, helped by the female. Over a week, she lays four white eggs, each weighing 1.5 grams – almost one-quarter of her weight. The male tops up the female’s food intake to help with the huge nutritional demands of egg production.
Riflemen can live for six years, but 1½ to three years is more usual.
Riflemen live in a variety of forest types: lowland conifer–broadleaf forest, high-altitude beech forest, mature tawa forest and mānuka–kānuka scrub.
They were once common throughout New Zealand, but farmland, towns and highways have fragmented their forest habitat. Riflemen don’t fly over open treeless ground, so once they disappear from an area they cannot return. In the North Island, they are found south of the Coromandel Peninsula (apart from Little Barrier Island and a tiny isolated group in Northland). Their distribution is patchy. In the South Island they still live in many forest areas of the main ranges, in bush patches on Banks Peninsula, Otago Peninsula and the Catlins. Their numbers have increased considerably where predators have been controlled. Riflemen have been relocated to Tiritiri Matangi and Ulva islands.
The North Island saddleback (Philesturnus rufusater) and South Island saddleback (Philesturnus carunculatus) are both known as tīeke to Māori. They belong to an old endemic family, Callaeidae (New Zealand wattlebirds).
Both species are glossy black with a chestnut-red saddle and rump, and red fleshy wattles hanging from the base of the bill. The North Island saddleback has a buff-coloured line at the front edge of the saddle. They hop on long, strong legs, and fly noisily for short distances. Their main call is an insistent, raucous ‘tee-kekeke’.
The South Island saddleback would be extinct if the birds had not been rescued by being moved to rat-free islands by the Wildlife Service in 1964, after ship rats invaded Taukihepa/Big South Cape Island. It was the first example internationally of a bird species being saved from extinction by human intervention. Rats were eradicated from Taukihepa in 2006, and saddlebacks were reintroduced there in 2011–12.
Saddlebacks were very common when European settlement began. But as rats, stoats and ferrets spread they declined rapidly, until they were left on only a few rat-free islands. They roost and nest in holes, often near the ground, so are easily caught. The removal of predators from islands and fenced mainland sanctuaries has allowed many new populations of South and North Island saddlebacks to become established. Where food is plentiful, they raise several broods a year.
Saddlebacks eat insects, fruit and nectar. Their specially adapted jaw allows them to open their bill forcefully, and prise open decaying wood looking for grubs, wētā and other large invertebrates. Like parrots, they sometimes hold food with one foot and tear it apart with their bill.
The stitchbird or hihi (Notiomystis cincta) was once thought to belong to the honeyeater family, but a recent genetic study suggests it is closer to the Callaeidae (New Zealand wattlebirds). However, it feeds in a similar way to the honeyeaters.
The English name describes the bird’s short clicking call, which sounds like machine stitching. The Māori name, hihi, means rays of the sun or feelers. It refers to the male’s yellow breast plumage, or to the bird’s facial whiskers – which also earn the brown female the name mata-kiore (rat-face).
Stitchbirds are 18 centimetres long. The male weighs 40 grams and the female 30 grams.
Males and females have quite different plumage. The male has a black head, chest and back, with white ‘ear’ tufts that stand erect during displays. The black edge is bordered with rich yellow, and wings are contrasting yellow and black with a white wing-bar. The female is greenish brown with a white wing-bar. Stitchbirds usually hold their tails erect when perching, in a similar posture to the related saddlebacks. Their bills are short, and they have very long, brush-tipped tongues.
Stitchbirds feed on nectar, berries and invertebrates.
Stitchbirds nest in tree holes, which makes it difficult for them to escape from predators. They occasionally mate face to face – something not seen in any other bird. Some are monogamous, while others (male or female) have more than one mate. In monogamous pairs, males help feed the chicks. The oldest known stitchbird lived seven years.
Stitchbirds were common around the North Island until the 1870s, but by 1885 were found only on Little Barrier Island. Since 1980, some have been moved to other islands and sanctuaries. This has sometimes been successful, but their food needs have not always been met, partly because of competition from tūī and bellbirds. Supplementary feeding with sugar water helps overcome this problem.
The bellbird and tūī belong to the Meliphagidae or honeyeater family.
Bellbirds or korimako (Anthornis melanura) are beautiful singers. At dawn and dusk they form a rolling chorus that can fill a valley for many minutes. They also sing solo at any time of day. Male and female perform duets, and birds sing against each other to define territorial boundaries. Young birds learn from neighbours, so the tunes vary from place to place, forming a ‘local dialect’. Māori would compare a person’s fine singing or oratory to the korimako as a compliment.
Bellbirds are around 20 centimetres long, and dull coloured – olive and black with a red eye. Males have a purple head and weigh 34 grams; females weigh 26 grams and have a narrow pale stripe from the bill below the eye. The males in particular are bossy and intimidate smaller birds. Adults sometimes make a loud whirring noise with their wings as they fly.
There are three subspecies. One is found on the North, South, Stewart and Auckland islands, one on the Three Kings Islands, and one on the Poor Knights Islands. They are common in many forested areas but absent from others, including Northland. The larger Chatham Island bellbird (Anthornis melanocephala) is extinct.
Male bellbirds defend trees that contain prized foods, refusing access to stitchbirds and even female bellbirds. But they do let in their own mate during the breeding season. Tūī are even more stroppy. They pursue would-be trespassers (including bellbirds), shouting their alarm call, flapping, clacking their bills and even dive-bombing. They sometimes form aggressive mobs.
Bellbirds return to the same breeding territory each year. The female builds the nest and lays up to five pale pink eggs with reddish spots and blotches. She incubates these for 14 days, and leaves the eggs to feed, or is occasionally fed by the male. Chicks eat mainly insects and spiders. They fledge after two weeks, and continue to be fed for another week or two.
The tūī (Prosthemadera novaeseelandiae) has an exceptional vocal range, from harsh squawks, clicks and whirrs to bell-like melodies. Tūī mimic other birds and various sounds from their environment. Part of their range is beyond human hearing, so in the middle of a song they can seem to fall suddenly silent.
Māori sometimes trained tūī to talk, and some chiefs taught their caged birds complex speeches. To help them speak clearly, their brush-tipped tongues were trimmed.
Tūī are dark iridescent green with purple and azure highlights. They have two tufted white feathers under the chin, inspiring their other name, parson bird, as these look like a clergyman’s collar against their dark plumage. Lacy white feathers cover the back and sides of the neck. Males weigh 120 grams, females 90 grams, and they are 30 centimetres long. The Chatham Islands subspecies is bigger.
Tūī breed similarly to bellbirds.
The tūī’s name has been used for the Tui Music Awards, and for brands of beer, balms, rental campervans and garden products. The first women to serve overseas in the Second World War were named the Tuis, carrying out canteen duties in New Zealand forces clubs in Egypt.
Tūī and bellbirds are important pollinators of plants, including kōwhai, pūriri, tree fuchsia, flax and kākā beak. They transfer pollen on their foreheads while collecting nectar from the deep throats of these flowers. Tūī and bellbirds can twist open the flowers of two species of mistletoe.
They also spread the seeds of many plants – including tōtara, kahikatea, mataī, pittosporum and coprosma species, and other plants with fleshy fruit. The birds eat the berry, ‘clean’ the seed with stomach acid, and leave it at a new site with some fertiliser.
Adaptations for feeding on nectar include a curved bill, low forehead and long, brush-tipped tongue. Nectar and fruit are seasonal, so the birds need other foods. In beech forest, honeydew – a sugary liquid excreted by scale insects living on beech trunks – provides bellbirds and tūī with carbohydrate all year. Both species also eat invertebrates, which can form up to 85% of bellbirds’ energy intake. Tūī sometimes jump and thrash around on plants to disturb large insects.
Both species travel long distances seeking food. In winter they may move from small patches of bush into towns, where they feed on garden trees and shrubs that have diverse flowering and fruiting times.
New Zealand robins and tomtits resemble British robins, but the two groups are not closely related. The New Zealand species belong to the Australian–New Guinean family Petroicidae.
Robins and tomtits have large heads, short necks, round bodies and an upright stance. They have short bristles around the bill. Robins have long legs, and are larger than tomtits. All are insectivorous. The oldest known bird lived 16 years, but their life expectancy is three years.
North Island robins or toutouwai (Petroica longipes) are the largest of this group, 18 centimetres long and weighing 23 grams. They are darkish grey, with uneven white-grey underparts up to the chest, and a white dot above the bill. They feed mainly among leaf litter, collecting larvae, insects, worms and spiders, some of which they hide nearby. The male and female of a pair steal food from each other’s hiding places.
Feeding on the ground makes them vulnerable to predators, and their nests are easily accessible – so the species has disappeared from many areas. They are still found in forests of the western and central North Island, and on Little Barrier and Kāpiti islands – and they have been reintroduced to some sanctuaries where predators are controlled.
The South Island robin (Petroica australis) is similar to the North Island species, but is pale yellow underneath and more evenly dark on top. The male has a distinct boundary between the dark grey and pale yellow on its upper chest.
There are two subspecies – South Island and Stewart Island robins.
Black robins (Petroica traversi) are endemic to the Chatham Islands. They made a dramatic recovery from a low point of five birds in 1979, thanks to skilled management by staff of the New Zealand Wildlife Service and the breeding prowess of one female, Old Blue. The birds were moved to better habitats, and eggs were given to tomtits to raise so the robins would keep laying. By 2004, there were over 200 birds.
The New Zealand tomtit or kōmiromiro (Petroica macrocephala) has five subspecies – one on each of the North, South, Chatham, Snares and Auckland islands. They have a dark head, throat and back – black in males, brown in females – with white underparts. Males have a sharp dividing line across the breast, tinged with yellow in the South Island subspecies. Adults have a small white dot above the bill. The Snares Island subspecies is completely black. On average, tomtits measure 13 centimetres and weigh 11 grams.
The female builds a bulky nest in a tree fork, and is fed by the male while she incubates the eggs – then both feed the chicks. They raise up to three broods a year. Their diet is a wide range of invertebrates, which they catch by scanning a wide area and pouncing on prey. Their call, which has been compared to a squeaky wheelbarrow, sounds like ‘tea-oily-oily-oh’.
These are native species, but the silvereye is not endemic to New Zealand – it also occurs in Australia.
The fantail or pīwakawaka (Rhipidura fuliginosa) is 16 centimetres long, including its 8-centimetre tail. It weighs 8 grams. Most fantails are brown above and pale underneath. Their fan-like tail, usually held high above the body, is made up of long dark central feathers flanked by white feathers. About 20% of South Island fantails are completely black.
The fantail’s tail contributes to its distinctive flight – twisting and turning in the air as it catches insects in flight. Its call is like a kissing sound.
New Zealand’s fantails belong to three separate subspecies: one on each of the North, South and Chatham islands.
Fantails mainly eat insects. They build distinctive nests with hanging tails under protective foliage in tree forks, lay three or more speckled white eggs, and raise two to five broods in a season. The population fluctuates, but tends to recover quickly if it drops. The oldest bird known was three years. Fantails are common in forest, rural and urban environments.
Fantails topped a national poll as Bird of the Year in 2006. The birds appear tame and friendly – they follow people, snatching sandflies and other insects disturbed by human activity. They have also been great favourites with Māori, playing a prominent role in many legends.
The silvereye or waxeye (Zosterops lateralis) has a distinctive white ring around its eye. Its Māori name, tauhou, means stranger – it is a recent arrival, first noted in 1832 and established from 1856. It is now abundant all over New Zealand in a wide range of habitats – native forest, scrub, plantations, rural and urban orchards and gardens.
The silvereye has green wings and a grey back, is 12 centimetres long and weighs 13 grams. The same subspecies also breeds in Tasmania, migrating to Queensland each winter. In New Zealand, the birds form flocks in winter and move about in search of seasonal foods – invertebrates, fruit and nectar. Their flocking call is a liquid ‘kee-kee-kee’.
These three small insect-eaters belong to a family that is only found in New Zealand, Mohouidae. They tend to flock when feeding, usually high in the forest canopy, and have tuneful songs. All are at risk of having long-tailed cuckoo eggs laid in their nests.
The whitehead or pōpokotea (Mohoua albicilla) is a North Island bird with an off-white head, pale body, and brown wings and tail. On average they are 15 centimetres long; males weigh 18.5 grams and females 14.5 grams. Found in native and exotic forests, whiteheads have gone from some areas but are still widespread. They are abundant on predator-free islands, including Kāpiti and Little Barrier, and have been moved to Motuora, Mana, Moturoa, Motuihe, Motutapu and Rangitoto islands.
Whiteheads build a nest in the forest canopy or lower shrubs. Young birds from earlier clutches often help raise chicks.
The yellowhead, bush canary or mohua (Mohoua ochrocephala) lives in the South Island. Yellowheads are 15 centimetres long; males weigh 30 grams, females 25 grams. They are bright yellow with a brown back, wings and tail.
Yellowheads nest in tree holes, usually in beech trees. These are easier for predators to reach than whitehead nests, and the narrow entrance makes it difficult for the birds to escape. So yellowheads have disappeared from 85% of their range, including Stewart Island. There are remnant populations in Fiordland and other small pockets of the Southern Alps and Catlins. Many have been moved to sanctuaries around the South Island – to Ulva, Codfish, Breaksea, Chalky, Anchor, Pigeon, Secretary, Pomona, Resolution and Nukuwaiata islands, and islands in southern lakes.
The brown creeper or pīpipi (Mohoua novaeseelandiae) of the South Island and Stewart Island is the smallest of the three Mohoua species – 13 centimetres long. Males weigh 13.5 grams, females 11 grams. The head and back are brown, with a grey face and neck. Brown creeper numbers have fallen, but they remain in many areas of the Southern Alps, Nelson, Marlborough, Kaikōura, Banks Peninsula and the Catlins, and on Stewart Island and islands off its north-east coast, living in exotic pine forest and scrub as well as mature native forest. Young birds move from tree to tree in flocks of up to 50, chorusing their sweet ‘peee–pee–pee’ call.
The native grey warbler or riroriro (Gerygone igata) and the endemic Chatham Island warbler (Gerygone albofrontata) are New Zealand’s only members of the Australasian family Acanthizidae. They sing a delicate and complex trill, which Māori took as a seasonal reminder to plant their crops. The grey warbler weighs 6.5 grams; the Chatham Island species weighs 9 grams. Grey warblers have adapted well to human changes to the landscape, but Chatham Island warblers prefer undisturbed sites.
The female of both species builds an enclosed pear-shaped nest with a side entrance hole, usually hanging from a branch. She lays four white eggs with reddish speckles, each nearly one-quarter of her body weight, in seven days. The male defends the territory while the female incubates the eggs alone. Then he helps feed the chicks while she prepares to lay a second clutch.
A shining cuckoo may lay an egg into the warbler’s second clutch. The cuckoo chick hatches first and expels the warbler’s eggs or chicks. It is fed by the apparently unsuspecting warbler until it fledges.
Both species eat mainly invertebrates and some small fruits. They glean food from leaves, and sometimes the grey warbler hovers beside branches to catch prey.
Two cuckoo species breed in New Zealand. Both are migratory, arriving in spring to breed and flying north to Pacific islands for winter.
Like most cuckoos, both lay their eggs in the nests of other species, which incubate them and then rear the chicks.
Shining cuckoos or pīpīwharauroa (Chrysococcyx lucidus) breed in Australia, Vanuatu and New Caledonia as well as New Zealand. The New Zealand subspecies overwinter in the Bismarck Archipelago and Solomon Islands, and returns to New Zealand from late September. The shining cuckoo’s call – repeated ascending whistles followed by one or two long descending whistles – heralds spring.
Once they have mated and laid their olive-green eggs in grey warbler’s nests (one egg per nest), they are free of parental duties, but stay around for several months. They feed mainly on invertebrates, including a kōwhai-eating caterpillar. When ready to migrate they gather in flocks of several hundred.
Shining cuckoos are 16 centimetres long and weigh 25 grams. They have a metallic green back and white underparts with green bars.
Long-tailed cuckoos or koekoeā (Eudynamys taitensis) breed only in New Zealand. They migrate mainly to islands east of Fiji, including French Polynesia, but also further west into Micronesia. Long-tailed cuckoos place their creamy brown-blotched eggs (one per nest) in the nests of other birds – in the North Island the whitehead, and the South Island the brown creeper or yellowhead.
Their call is harsher and louder than the shining cuckoo’s – several ascending shrieks, sometimes followed by a loud pe-pe-pe-pe-pe. Their main foods are large invertebrates such as wētā, but they also eat skinks, geckos, small birds, eggs, chicks and fruit. Forty centimetres long, they weigh 125 grams. They have a heavy bill and a streamlined build, with a long tail. On the topside they are copper brown with horizontal black bars, and underneath they are pale with vertical brown streaks, which are finer in juveniles.
Parakeets or kākāriki (little kākā) are slender green parrots with long tails. Like other parrots, they have broad, curved beaks and are zygodactyl – they have two toes pointing forward and two backwards. The ancestor of New Zealand’s kākāriki species came from New Caledonia within the last 500,000 years, and evolved into six species spread between the subtropical Kermadec Islands and the subantarctic islands. All are now endemic – found only in New Zealand. They belong to the Cyanoramphus genus, which also includes other South Pacific parakeets.
Kākāriki make a chattering call as they fly and while feeding. They often hold food up to their mouth with one claw. In autumn and winter they search for food in flocks, but are more solitary during the breeding season.
The Māori saying ‘ko te rua porete hai whakarite’, meaning ‘just like a nest of kākāriki’, was used to describe a group of people gossiping excitedly.
The Antipodes Island parakeet is the largest. Males measure 32 centimetres from head to tail and weigh 130 grams. The smallest is the yellow-crowned parakeet. It is shorter – males are 25 centimetres long, females 23 centimetres – and much slighter. Males weigh just 50 grams and females 40 grams. The other parakeet species are within this range.
Parakeets were reasonably common when European settlers arrived in the 1840s, and were shot for feathers to fill pillows. Now they are legally protected, but introduced rats, cats and stoats have taken a heavy toll. None are common, having disappeared from much of their former range. Two mainland species – the red-crowned and yellow-crowned parakeet – are also quite abundant on some predator-free islands, and the orange-fronted parakeet has been moved to others.
Red-crowned parakeets (Cyanoramphus novaezelandiae) are green, with red from bill to crown, a thin red band past each eye and small red flank patches. They mainly eat the seeds of beech, tussock and flax, as well as fruits, flowers, leaves, shoots and invertebrates. They nest in trunks or crevices and burrows, laying about seven white eggs.
Feeding and nesting close to the ground means they are very vulnerable to predators. They are now absent from most of the South Island, and sparse in larger forested areas of the Ruahine Range, central North Island, and Northland. They are still doing well on stoat-free Stewart Island and some smaller islands as far south as the Auckland Islands. Separate subspecies are found on the Kermadec and Chatham islands.
Yellow-crowned parakeets (Cyanoramphus auriceps) are green, with yellow feathers on the crown meeting a red band above the bill. They live in conifer–broadleaf and beech forest as well as scrub, in both the North and South islands. They mainly feed in the treetops, eating scale insects, leaf miners and aphids, the buds or flowers of kānuka, rātā and beech, and beech seeds. They usually nest in holes in old trees, laying five or more white eggs. Some remain in South Island native forests and the larger forests of the central North Island. On the mainland they are more widespread and common than red-crowned parakeets, but on most predator-free islands the red-crowned species dominates.
The least common species is the orange-fronted parakeet (Cyanoramphus malherbi), which is green with a yellow crown meeting orange above the bill. It once lived in the South Island, on Stewart Island and as far north as Hen (Taranga) Island, but is now only found in a few North Canterbury valleys of the Southern Alps.
In 2001, its population – already low at 700 – fell below 200 when a bumper crop of beech seed (its main food) also triggered a huge increase in the number of rats, which prey on the eggs and chicks. Intensive efforts to prevent extinction were made: better predator control, cross-fostering eggs to other birds, and moving some birds to predator-free islands in Fiordland (Chalky Island), the Marlborough Sounds (Maud and Blumine islands) and Tūhua (Mayor Island) off the coast of Tauranga.
The mainland red- and yellow-crowned parakeets occur at sites as distant from New Zealand as the Auckland Islands. A subspecies of red-crowned parakeet is found in the Kermadec island group, and another on the Chatham Islands.
The Chatham Islands have a local endemic species, Forbes’ parakeet (Cyanoramphus forbesi). Subantarctic Antipodes Island has two – the all-green Antipodes Island parakeet (Cyanoramphus unicolor) and the red-crowned Reischek’s parakeet (Cyanoramphus hochstetteri). Both live in a treeless habitat, nesting in metre-deep burrows at the base of tussock clumps. They feed on tussock leaves, seeds and other plant material. The Antipodes Island parakeet scavenges fat from dead chicks at penguin colonies, and sometimes seeks out and kills storm petrel chicks in their burrows.
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