Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Suborder: Acanthisitti
Family: Acanthisittidae
Genus: Acanthisitta
Species: A. chloris
Binomial name:  Acanthisitta chloris
Common name: Rifleman, Tītipounamu

The Acanthisitta chloris consists of two subspecies and they are New Zealand's smallest endemic bird, with fully grown adults reaching around 8 cm. The South Island subspecies is Acanthisitta chloris chloris and the North Island subspecies is Acanthisitta chloris granti. The rock wren and rifleman are the only two surviving New Zealand wrens. 

The male Acanthisitta chloris is bright green on the dorsal side while the female is of a more sombre brownish tone and her head and back are flecked with ochre. Male birds typically weigh around 6 g, females 7 g. Both birds are white on their under surfaces and have white eyebrow stripes. They have short, rounded wings, a very short tail, and a long thin awl-like bill which is slightly upturned for insertion into cracks. The Rifleman flies quickly with a wing beat producing a characteristic humming sound like a hummingbird.

The true habitat of this bird is thinly wooded forests. The North Island Rifleman, granti is sparsely distributed in forests south of the Waikato and has been rediscovered in Te Waipoua forest in Northland. It is common on Little Barrier and Great Barrier Islands. In the South Island subspecies, Acanthisitta chloris chloris is found in high altitude beech forest or lowland areas with podocarp forest. It is not in Taranaki.

The Acanthisitta chloris is insectivorous and searches for maggots and small insects on tree trunks and among leaf litter on the forest floor. The bird begins its search from the base of a tree and climbs up it progressively, spiralling up around the trunk. Upon finishing its search of a particular tree, the bird glides to the foot of a neighbouring tree and begins its search again.

Acanthisittids build their nest in rock fissures, holes in tree trunks, or even in cavities in the ground. The nest entrance is often so narrow that the bird struggles to get inside. The nest most commonly has a dome shape and is finely interwoven with blades of grass, down feathers and other kinds of light material. Brooding lasts 13–15 days with the female laying 4-5 eggs. Two broods per year are common.

The South Island Acanthisitta chloris chloris

A video of the rifleman
VIDEO  

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