Happy World Sparrow Day on March 20th

Word Sparrow Day, observed annually on March 20th, is an international initiative meant to rise awareness of the rapid decline of House Sparrows (Passer domesticus) in recent decades. While the species is closely associated with urban environments and used to do well living close to humas, their rapid decline in numbers has been observed in many places around the world, ranging from America to Western Europe and parts of Asia. One notable exception is European metropolis Berlin, where the species is thriving.  

The cause for this worldwide population decline isn’t completely understood – and in fact, a combination of several causes is likely. Among the proposed causes is the simultaneous decrease in insects, an important food source for sparrows. Also, new urban buildings provide fewer opportunities for sparrows to build nests when compared to older buildings. Furthermore, competition with other bird species and increased predation by cats have been proposed for the decline.

In Kuopio, the species has also been rapidly declining since the late 1970ies, based on data about observed individuals in the central area of Kuopio during the mid-winter census. While there were around 900 individuals reported in the early 1960ies and between 500 and 600 around 1990, numbers have dropped rapidly since 1998. In recent decades, less than 100 individuals have been reported in the area of the city center during the census. Less than 100 breeding pairs have been estimated in the central area nowadays, with a new survey being conducted in the spring of 2024.

Intern at City of Kuopio, Environmental Protection Unit, and  International Masters degree student at UEF (Biology of Environmental Change)
Yvonne Wiese (in English), 044  718 2187, yvonne.wiese(at)kuopio.fi