House Sparrows (passer domesticus) were introduced to New Zealand first in the mid 1860s. They soon became abundant and were said to be combating plagues of agricultural pests. By the 1880s, however, they were regarded as pests. Sparrows have made their own way to offshore islands, breeding on those with human habitation. Males are smart chestnut-brown, white-and-grey with a distinctive black “bib”; they are difficult to confuse with any other species. Females and young lack the bib and are greyer, with lighter brown dorsal plumage than the male. Their underparts are plain grey, but their backs and wings are variegated several shades of brown and white. The robust conical bill is black in breeding males, otherwise pale pinkish-brown. The eyes are dark brown and legs dull pink.
REF: NZ Birds Online