In all the major cities of the world, the number of sparrows is decreasing. SEO warns that the drop has been 21%, which represents a loss of 30 million birds in just a decade.
The sparrow is a small bird that left its natural habitat and decided to settle on the patios, sidewalks, streets, gardens or roofs of our houses hundreds of years ago.
It has already disappeared from cities such as London, Brussels, Antwerp or Hamburg. In Spanish cities, this type of bird has decreased by 21%, which has led to the disappearance of about 30 million of these birds, according to the balance made by the Spanish Ornithological Society (SEO).
“This decline is alarming, because if the regressive population trend does not stabilize, we could very soon find fields and cities with hardly any sparrows”Says the entity's report.
What causes the sparrow descent?
Birds in general, and birds in particular, began to be affected in the 18th and 20th centuries with the appearance of the automobile and the industrialization of agriculture through the intensive use of pesticides. Today the decline continues due to urban development in large cities. The architectural style and the demolition of old buildings, do not leave corners where sparrows can nest.
Adding to the cause of the decline in birds is the scarcity of insects due to the excessive use of plant protection products, the paving of parks and gardens or the presence of exotic plants.
Without insects, sparrows feed unbalanced, eating "junk food" (food or food scraps from humans) that do not provide the necessary amount of essential nutrients such as fatty acids, vitamins or minerals that this species needs.
Exposure to air, noise and light pollution also affects the quality of life of sparrows as it can cause stress and trigger hormonal disorders that accelerate their aging.
"Air pollution not only threatens the house sparrow, it is estimated that 400,000 people are killed each year in the European Union," they state from the SEO report, as according to them, a group of Swedish and Dutch researchers have found that This type of contamination reduces the life expectancy of these birds due to the alteration of their immune system.