House sparrows are well-adapted to living in urban areas, so it is surprising their numbers have fallen significantly over the past decades. An investigation into this worrying trend finds that sparrows living in urban areas are adversely affected by pollution and poor nutrition. The study also finds the birds suffer more during the breeding season, when resources are needed to produce healthy eggs.
Click on the link to read the rest of the article: House sparrow decline linked to air pollution and poor diet: City sparrows suffer from more stress than their country cousins, find Spanish researchers, especially during breeding season — ScienceDaily