In comparison with finches, sparrow flight generally is more direct, almost laboured, and usually low. The young of greenfinches are greenish above their shorter tail. Chaffinches differ in their distinctive double wing-bar and white outer tail. They usually stay close to cover, and are never in large flocks. Dunnocks are smaller, with darker, more sombre plumage, and a slender dark bill. Similar species: females and juveniles can be confused with dunnock, greenfinch or chaffinch. Voice: the familiar unmelodious chirp is the male’s song, and the same call is used by both sexes in roosts and other social gatherings. The eyes are dark brown and legs dull pink. The robust conical bill is black in breeding males, otherwise pale pinkish-brown. Their underparts are plain grey, but their backs and wings are variegated several shades of brown and white. Females and young lack the bib and are greyer, with lighter brown dorsal plumage than the male. Males are smart chestnut-brown, white-and-grey with a distinctive black “bib” they are difficult to confuse with any other species. The best source of information on sparrow biology is the monograph by Summers-Smith, although adjustment for the six-month difference in seasons is necessary. They have evolved differences in morphology in response to local environments. Sparrows have made their own way to offshore islands, breeding on those with human habitation. By the 1880s, however, they were regarded as pests. They soon became abundant and were said to be combating plagues of agricultural pests. House sparrows were introduced to New Zealand first in the mid 1860s. There is even a scientific journal devoted to work on the house sparrow and other Passer species. This ubiquity has led to many studies of it as a pest and of its physiology, energetics, behaviour, genetics and evolution. It lives mostly in close association with man. One of the world’s most successful introduced species, the house sparrow is found from sub-Arctic to sub-Tropical regions everywhere, except Western Australia and some small islands.
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