House Sparrow Passer domesticus (Linnaeus, 1758)
House Sparrow is a well-known bird. Its natural range included Eurasia and North Africa. Since the mid-nineteenth century House Sparrows were introduced in many countries of Africa, North and South America, in Australia and New Zealand and also to several oceanic islands. Later on the birds spread on their own thanks to unwitting assistance of humans. House Sparrow is widespread in towns, villages, farms and avoids territories which are far from human settlements. In areas with chalk outcrops House Sparrows settle in niches in chalk ravines and chalk pits, but always near villages and other settlements.
The plumage of House Sparrow is a mix of brown and gray colour shades. Males and females differ strongly in colour. Dull brown colour predominates in female’s plumage. Male’s plumage manifests a marked contrast between grey crown & chest, greyish underparts, warm brown back and black eye-stripe & bib.
House Sparrows are multi-brooded with up to 4 broods per year. They nest usually in holes –hollows of a tree trunk, in cavities, niches and burrows, but can build free-standing globular nests in the branches of trees. During breeding period House Sparrows nest in isolated pairs or in loose colonies. Females lay 2-7 eggs, both sexes brood and feed young. Food of young includes mostly invertebrates, for example, caterpillars and other insects with soft bodies. The male cares for the fledged young for some time, and then young individuals join together in flocks and possess their usual social way of life.
House Sparrow is a principally sedentary species throughout its range. In the course of a year sparrows form communal roosts which become noticeable in non-breeding period. When the cold weather came some sparrows return to roost in old nests, other individuals bring nest material to small niches and use these potential nest sites for roosting. But many birds continue to congregate and roost together.
Despite its impressive success in the past House Sparrow is now in decline in some countries of Europe and North America. The main cause for the reduction of numbers in countryside is changes in farming practices. The use of pesticides led to the shortage of food resources for nestlings. The development of farm machinery which eliminated the spillage of grain seeds on agricultural fields resulted in reduction of food resources for adults. In cities and towns the principal cause of decline is in reduction of permanent food supply. First of all, food waste becomes increasingly less available for these birds due to substantial growth of public amenities in urban areas and owing to widespread usage of plastic bags. Secondly, the area of urban wastelands where sparrows search for seeds and insects reduces. All such transformations threaten House Sparrows which were constant companion of humans until recently.
Text by O. Bresgunova
Photos by E. Skorobogatov, O. Bresgunova