New Zealand wren

New Zealand wrens
Temporal range: Miocene–present
The winter range of the New Zealand rock wren remains a scientific mystery
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Suborder: Acanthisitti
Wolters, 1977
Family: Acanthisittidae
Sundevall, 1872
Extant and subfossil genera

Traversia
Acanthisitta
Xenicus
Dendroscansor
Fossil genus, see text

The New Zealand wrens are a family (Acanthisittidae) of tiny passerines endemic to New Zealand. They were represented by seven Holocene species in four or five genera, although only two species in two genera survive today. They are understood to form a distinct lineage within the passerines, but authorities differ on their assignment to the oscines or suboscines (the two suborders that between them make up the Passeriformes). More recent studies suggest that they form a third, most ancient, suborder Acanthisitti and have no living close relatives at all. They are called "wrens" because of similarities in appearance and behaviour to the true wrens (Troglodytidae) but are not members of that family.

New Zealand wrens are mostly insectivorous foragers of New Zealand's forests, with one species, the New Zealand rock wren, being restricted to alpine areas. Both the remaining species are poor fliers and four of the five extinct species are known or suspected to have been flightless. Along with the long-legged bunting from Tenerife, one of the Canary Islands, they are the only passerines known to have lost the ability to fly. Of the species for which the plumage is known, they are drab-coloured birds with brown-green plumage. They form monogamous pair bonds to raise their young, laying their eggs in small nests in trees or amongst rocks. They are diurnal and like all New Zealand passerines, are, for the most part, are sedentary.

Like many New Zealand birds, New Zealand wrens suffered several extinctions after the arrival of humans in New Zealand. Of the seven Holocene species, only two survive today. The South Island stout-legged wren, North Island stout-legged wren, and long-billed wren became extinct after the arrival of the Māori and the Polynesian rat. They are known to science only from subfossil remains. At the same time, Lyall's wren became extinct on the main islands and survived only as a relict population on Stephens Island in the Cook Strait. Lyall's wren and the bushwren became extinct after the arrival of Europeans in 1895 and 1972 respectively. Of the two remaining species, the rifleman is still common in both the North and South Islands. The New Zealand rock wren is restricted to the alpine areas of the South Island and is considered vulnerable.