The North Island robin often come within a couple of metres to people, and occasionally stand on a person’s boot.
North Island robins measure 18 cm from beak tip to tail tip, and weigh about 35 grams, and so are slightly larger than a house sparrow. They have long, thin legs and an upright stance.
The North Island robin is one of three sub-species of the New Zealand robin, each found on one of the main islands:
They are dark slaty-grey with a pale greyish-white lower breast and belly
- North Island robin (Petroica longipes)
- South Island robin (Petroica australis australis)
- Stewart Island robin (Petroica australis rakiura)
The first two sub-species are not threatened, but the Stewart Island robin is ‘nationally vulnerable’ because of the impacts of introduced predators.
They are all New Zealand robins although, strictly speaking, the North Island robin is a completely different species from the other two subspecies
North Island robins are dark slaty-grey with a pale greyish-white lower breast and belly. The upper dark feathers have pale shafts and so the birds appear faintly streaked.
Exact colouration depends on age and sex. Males older than three years of age are almost black over the upper parts, while females and most males less than two years old are mainly pale to dark grey above.
Both sexes have a small patch of white feathers at the base of the beak which is kept covered much of the time, occasionally being flashed when interacting with robins and other small forest birds.
Where to find them
The North Island robin is found in native and exotic forests, mainly in the central North Island from Taranaki through to the Bay of Plenty. In addition, populations occur on Little Barrier and Kapiti Islands.
They can be found in native and exotic forests
Since 1991, populations have been established on several predator-free islands (Mokoia, Tiritiri Matangi, Tuhua, Matiu/Somes, Mana, Moturoa) and several mainland sites which are encircled by predator-proof fences (Karori Sanctuary, Bushy Park Reserve).
They have also been established in other locations where mammalian predators like rats, stoats and possums, have been controlled to very low levels.
Their diet consists mainly of invertebrates, including aphids, tree weta, stick insect, or earthworm
The robin’s diet consists mainly of invertebrates, including species from the size of aphids to those as large as an adult tree weta, stick insect, or earthworm. Items too large to swallow whole are taken to the ground and flung from side to side against the ground or log until broken into pieces.
Although robins are unable to eat such large prey items all at once, the excess is not wasted. Uneaten portions are stored in crevices, holes or depressions on trunks and branches of trees near where the item was found, to be retrieved and eaten later in the day or the next day. In late summer-autumn, when conditions are dry and there is little invertebrate prey available, robins supplement their diet with small berries and fruit.
Breeding and nesting
Although the oldest robin known lived to at least 16 years of age, most have a much shorter lifespan. Both sexes start breeding when one year old. The breeding season of the North Island robin starts in September and extends to February. At sites where food is readily available, pairs rear two, and occasionally three, broods in a season.
The nest, commonly built in a trunk or branch-trunk fork, consists of an outer layer of twigs, fibers and moss bound together with cobwebs. The inner layer consists of moss, fine grasses, and/or tree fern scales.
As well as building the nest on her own, the female incubates her clutch of 2-3, unusually 4, eggs on her own. However, during both of these phases of the nesting cycle, her mate brings her food about 3 times an hour through the day. Incubation lasts about 18 days, chick-rearing about 21 days. The male assists with chick-rearing, and once the chicks have left the nest, each parent looks after particular fledglings.
Songsters of the forest
Male robins are renowned songsters of the forest. From August to December, males spend much time loudly singing from high perches in the canopy, especially in the early morning.
Bachelor males also spend much time through the day giving full song in an attempt to attract a mate. Full song consists of a variety of simple notes strung together and sustained for up to 30 minutes with regular brief pauses.
Male robins are renowned songsters of the forest
During European settlement, and the clearance of much native forest for pasture, the range of the North Island robin declined markedly. But, in the past 30 years there has been little change in its distribution.
However, not all is well for this robin. Introduced predators, particular ships rats, possums, stoats and feral cats continue to impact robin populations, taking many eggs, nestlings and recent fledglings. In addition, because females carry out all incubation and chick-brooding duties, a significant proportion are killed at night by introduced predators.
What this means
Some males are unable to find mates, and spend much of the breeding season singing to attract one. As well as there being more males than females in many areas, much suitable habitat is occupied by fewer robins than would be expected because of the high incidence of predation. It is only on predator-free islands, in predator-free fenced sanctuaries, or sites where introduced predators are controlled to low numbers that healthy populations of robins exist.
DOC has established robin populations by translocation at a number of sites in the North Island. This is partly to enable people interested in New Zealand’s birdlife to see and hear this interesting species.
Robin’s nature make them very easy to monitor
DOC has also helped trusts and community groups to establish robins at several other sites.
The robin's trusting nature makes it a favourite with people because they can get close to the bird unlike other native birds.
There are several characteristics of the robin’s nature that make it a very tractable species for monitoring:
- They can be caught by a variety of methods
- Have relatively long legs and so colour-bands can be readily seen
- Will approach researchers for a small food (mealworms) handout
- Their nests can be readily found and monitored without the birds abandoning them.
This has enabled the survival of individuals and nesting attempts to be monitored by DOC staff to determine the effectiveness of predator control operations.
Toutouwai - Robin's Return project
Toutouwai have been returned to Moehau in the northern Coromandel Peninsula as part of the 'Toutouwai - Robin's Return' project. The aim was to create a self-sustaining population of North Island robin and return the bird to part of their former home.
More on Toutouwai – Robin's Return.
You can help
North Island robin will benefit from pest control
There are a couple of ways you can protect robins if they are in your region.
Fence forest blocks
Fence forest blocks to prevent them being grazed by stock. This will enhance their value to robins and other native fauna.
You can help control predators (possums, feral cats, rats and stoats) by trapping and poisoning.
By controlling these predators to low numbers, robins can breed much more successfully than otherwise (70% compared to 20%).
As a result, within the first year of such a pest control operation, the robin population often doubles in number, and most males are able to obtain a mate.