Andrzej Węgrzynowicz
Ornis Polonica 2013, 54: 225–236
https://doi.org/10.12657/ornis.2013.4.0
Abstract: The paper presents an analysis of changes in the House Sparrow Passer domesticus numbers in Polish cities and towns from the 1960s to the first decade of the 21st century based on published data. The long-term data from 294 study plots (50.6 km²) illustrate changes in numbers of breeding House Sparrows, and allow to calculate mean densities for successive decades. Data collected in 34 Polish cities and towns, in two types of urban habitats – housing estates and parks (including cemeteries and squares) were used. The frequency of occurrence of the House Sparrow in housing estates has not changed over the years – it was recorded as a breeding species on 98–100% of plots in particular periods. In 1960–1979, 1980–1989 and 1990–1999, mean densities of House Sparrows in this habitat ranged from 57.3 to 84.2 pairs/10 ha. However, in the 2000s the density was much lower (18.5 pairs/10 ha). The frequency of occurrence in parks, a suboptimal habitat, decreased from 62–76% in 1960–1999 to 34% in the 2000s, and the mean densities from 5.5–9.1 pairs/10 ha to 1.4 pairs/10 ha, respectively. The results indicate that the sharper decline of the House Sparrows numbers in Polish cities/towns began on the turn of the 20th century and has been continuing until now, but some signals of a crisis in the House Sparrows population had been recorded before.
Keywords: decline in abundance, House Sparrow, Passer domesticus, urban habitats
