Whitehead

Mohoua albicilla (Lesson, 1830)

New Zealand status: Endemic

Conservation status: Not Threatened

Other names: pōpokatea, popokatea, pōpokotea, popokotea

Geographical variation: Nil

Whitehead. Foraging. Kapiti Island, May 2008. Image © Duncan Watson by Duncan Watson

Whitehead. Foraging. Kapiti Island, May 2008. Image © Duncan Watson by Duncan Watson

Whiteheads are gregarious songbirds that live in noisy groups of up to 8 members and that are often heard before they are seen. They are only found in the North Island where they inhabit mostly the canopy regions of tall dense forest. Their numbers have been in decline but relocations in recent years have seen some very good results with several newly established populations. Whiteheads are the only North Island hosts for the long-tailed cuckoo.

Identification

Whiteheads are small songbirds with a compact body, short tail and bill and long legs. The head and underparts are white or whitish. Upperparts, wings and tail are brown-grey. Bill, legs and eyes are dark.

Voice: whitehead song is a characteristic viu viu viu zir zir zir zir or canary-like twitter. Several other chirps or chatters are used for constant communication within the group.

Similar species: although some species such as sparrow and silvereye are similar in size, the distinct white head and underparts make the whitehead easily distinguishable from other small passerines.

Distribution and habitat

The whitehead occurs only in the North Island of New Zealand. Its mainland distribution is south of a line connecting the Pirongia Forest, Hamilton and Te Aroha. It is locally common though patchily distributed south of this line, and to the north is limited to offshore islands and one fenced translocation site. Whiteheads are naturally common on Little Barrier and Kapiti Islands, and have been successfully introduced to Tiritiri Matangi Island, Motuora Island and Tawharanui Regional Park in the Auckland area, plus Maungatautari, Mana Island and Karori Sanctuary. Attempts to establish whiteheads in the Waitakere ranges (Ark in the Park) and at Cape Sanctuary (Hawke’s Bay) are continuing, and in 2011 or 2012 they were released on Moturoa Island (Bay of Islands) and Motuihe, Rangitoto and Motutapu Islands in the Hauraki Gulf.

Although found most commonly in tall native forest and dense shrubland, whiteheads also occur in mature pine plantations.

Population

Whiteheads are abundant on some pest-free offshore islands and mainland sites where predatory mammals are effectively controlled or excluded. They can be among the most abundant forest birds present at these sites (e.g. on Kapiti and Little Barrier Islands).

Threats and conservation

In the past, whitehead numbers declined dramatically due to forest clearance and predation by introduced mammals (particularly ship rats and stoats). They are reluctant flyers that do not often cross open ground, and so are very vulnerable to habitat fragmentation, as local populations that die out cannot be replenished. In the late 1800s, whiteheads disappeared from the northern North Island including many offshore islands in the Hauraki Gulf. They survived on Little Barrier and Kapiti Islands and these two populations have been used as source populations for numerous translocations.

Breeding

Whiteheads produce a single clutch per season from October to January. Nests are tightly woven, neat cups lined with fine materials such as natural fibres or moss. They are usually built in tree forks, hidden in dense canopy vegetation. Clutches usually contain 3 eggs, laid on consecutive days by the primary female. The female is also the sole incubator. The primary male or helpers may feed her as well as her young, both on and off the nest. Whiteheads are very inconspicuous around their nest which makes nests hard to find. Incubation takes about 18 days, and the chicks leave the nest when 16-19 days old.

Whiteheads are host to the brood-parasitic long-tailed cuckoo. The cuckoo lays her egg into the whitehead’s nest, and the whitehead incubates it along with her own eggs. After the cuckoo chick hatches, it ejects whitehead eggs and/or chicks from the nest and is raised by itself.

Behaviour and ecology

During the breeding season, whiteheads form very vocal, sedentary groups. These groups may break up or disperse to increase their foraging areas during the non-breeding season, when they can also be seen foraging in mixed-species flocks. Whiteheads are reluctant fliers but they move quickly through the canopy and are acrobatic when foraging, often hanging upside down.

Food

Whiteheads consume insects (especially caterpillars and beetles) and spiders, and sometimes take fruit or other plant material.

Weblinks

http://en.wikipedia.org/wiki/Whitehead_(bird)

http://nzbirds.com/birds/whitehead.html

References

Gill, B. 1990. The whitehead; gregarious bird of North Island forests. Forest & Bird: 38-39.

Heather, B.D.; Robertson, H.A. 1996. The field guide to the birds of New Zealand. Viking, Auckland.

Higgins, P.J.; Peter, J.M. (eds) 2002. Handbook of Australian, New Zealand and Antarctic birds. Vol. 6, pardalotes to shrike-thrushes. Oxford University Press, Melbourne.

Leuschner, N.; Brekke, P.; Cope, T. 2007. Longevity of a whitehead (Mohoua albicilla) on Tiritiri Matangi Island. Notornis 54, 233.

McLean, I.G.; Gill, B.J. 1988. Breeding of an island-endemic: the New Zealand whitehead Mohoua albicilla, Pachycephalinae. Emu 88: 177-182.

Miskelly, C.M.; Powlesland, R.G. 2013. Conservation translocations of New Zealand birds, 1863-2012. Notornis 60: 3-28.

Recommended citation

Leuschner, N. 2013. Whitehead. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz

Whitehead

Social structure
co-operative breeding groups
Breeding season
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
Nest type
woven cup
Nest description
Tightly woven cup in dense canopy vegetation.
Nest height (mean)
2.5 m
Nest height (max)
30 m
Maximum number of successful broods
2
Clutch size (mean)
3
Clutch size (min)
2
Clutch size (max)
4
Mean egg dimensions (length)
20 mm
Mean egg dimensions (width)
15 mm
Egg colour
White, variable speckled orange-brown.
Egg laying dates
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
Interval between eggs in a clutch
24 hours days
Incubation behaviour
female only
Incubation length (mean)
18 days
Incubation length (min)
17 days
Incubation length (max)
19 days
Nestling type
altricial
Nestling period (mean)
17 days
Nestling period (min)
16 days
Nestling period (max)
19 days
Age at fledging (mean)
17 days
Age at fledging (min)
16 days
Age at fledging (max)
19 days
Age at independence (mean)
Young fed up to 9 months of age
Age at first breeding (typical)
1 year
Maximum longevity
16 years
Maximum dispersal
Unknown