The number of sparrows has been reduced by up to 60% in four years due to the replacement of natural grass with artificial grass in parks, according to researchers from the Institut Cavanilles de Biodiversitat y Evolutiva Biología of the University of Valencia and the University of Alicante

The common sparrow is a species that has been associated with humans since Prehistory. However, since the beginning of the twentieth century, its population has fallen dramatically in rural and urban areas throughout Europe due to factors such as urban pollution, lack of space to nest, difficulties in finding food, diseases and predation.

In central London, today it is practically extinct, while in 1925 records speak of more than one hundred million birds, according to the study.

An article published recently in the Urban Ecosystems magazine is the result of a study carried out over four summers, between 2015 and 2018, showing the impact of replacing the soil in parks (grass, bare soil) with other artificial components (concrete, artificial grass , areas for dogs, pavements).

Of the 32 Valencian parks that were studied in four different locations, major changes were carried out in ten of them. However, in both types of parks, both those that were remodelled and those that stayed the same, the abundance of sparrows was similar at the beginning.

In the parks that remained the same the population declined 15%, while in those that underwent change the decline averaged 60% in the same period.

In their investigation, the universities were asked to suggest new urban planning policies with the urgent need to conserve the common sparrow and other birds.

Their proposal was to use using native trees, or grass species that require less water consumption for the parks, which would increase the number of invertebrates available for the support of sparrows.