Sparrow is a popular name for a genus of finches, of which the best known is the house sparrow (Passer domesticus). The house sparrow is a small, black-streaked brown finch found across the world, though once very common during the later part of the 20th century the sparrows declined rapidly for reasons unknown. The house sparrow builds a bulky, untidy nest of whatever materials are available, such as hay, straw, roots, rag, string, bits of paper, but it is always lined with soft feathers. The eggs are white in colour with a blue or green tinge and variously streaked or spotted with brown or purple. The house sparrow eats insects. House sparrows have been seen carrying a young offspring on their back, though this behaviour is very rarely witnessed, and the reason for it is unknown.
The tree sparrow (Passer montanus) is slightly smaller than the house sparrow, has brown plumage and a white collar around the throat and two white bars on the tail. The tree sparrow nests in hollow trees, under the thatch of old buildings and in holes in rocks. Research Sparrow
Abbreviations
Nature
Research Sparrow