House Sparrow (Passer domesticus) Science Article 6
The house sparrow Passer domesticus is unique among wild birds in its close association with, indeed virtual dependence on, man. Not only in the agricultural environment, where presumably this association first evolved, but also in built-up areas. It would be expected that, with man’s dominance of the world, the future would be bright for the bird, but it is now becoming evident that this is not the case, particularly in the highly developed region of western Europe. In Britain, the Common Bird Census launched by the British Trust for Ornithology in 1962 provided such a basis. This enquiry showed a major decline in the house sparrow population in farmland beginning in the latter half of the twentieth century, though this now appears to have stabilised, albeit at a lower level. This decline, which also affected a number of other farmland species, has been well studied and is now accepted to be the result of the intensification of agricultural practices that have led to a reduction in the availability of food. The spillage of oats from the nosebags of horses and the presence of undigested seeds in the droppings must have provided a major source of food for urban house sparrows.
J. De Laet and J. D. Summers-Smith, J Ornithol (2007) 148 (Suppl 2):S275-S278