Rock sparrow

The Rock Sparrow (Petronia petronia) is similar to a female Italian sparrow and European sparrow but can be distinguished primarily by the conspicuous yellow patch on its chest. Distributed in Southern Europe, it is a species typically found in the Mediterranean region, widespread in Southern Italy, but also sporadically reported in the Western Alps, in open and sunny environments of xeric sectors in some internal valleys. It is omnivorous, feeding on seeds and insects.

For years, a population of Rock Sparrows has nested in the mown and grazed meadows of the upper Susa Valley, in two sites of the Natura 2000 network managed by the Alpine Parks of Cozie Alps. It has colonized an area of about 13 square kilometers on the south-southwest slope in the municipalities of Sestriere and Cesana Torinese, between 1350 and 2000 meters above sea level. The territory is characterized by xeric pastures and mountain meadows which have seen a drastic decrease in traditional agro-pastoral practices in recent decades, leading to a risk of invasion by shrubs and trees and a loss of the high degree of plant and animal biodiversity associated with mown and grazed meadows.

Typically gregarious, it breeds on the edges of mountain villages where it prefers to build its nests in deep holes near ruined buildings, not shying away from cavities in trees, among rocks, or in nest boxes specially prepared for scientific research.

The research project

From 1988 to 2013, the population was studied as part of the Petronia Project, conducted by the Department of Biology, Ecology, and Earth Sciences of the University of Calabria along with other European universities and the University of Calgary (Canada) in collaboration with the Natural Park of Val Troncea. The research goal was to analyze the influence of climatic and landscape variations on the population dynamics of the Rock Sparrow, including its trophic strategies, local survival, and dispersal.

To monitor the nesting stages, nest boxes specially designed to meet the species' needs (dimensions 11x12 cm and 50 cm deep with an oval entrance hole of 5x3 cm) were installed, capable of functioning as capture devices when necessary for scientific purposes.

Ringing, carried out by park rangers, was one of the key operations of the project aimed at individually identifying the individuals forming the study population. All breeding adults and chicks were individually marked with colored rings to recognize the animals and ascertain social and pair bonds through direct observations. Over 22 years of the project, a total of 2802 birds (228 adults and 2574 chicks) were ringed, and 633 broods were recorded, including both first and second annual broods.

Even today, after the project has ended, park rangers continue their work maintaining nest boxes and monitoring the species.

Conservation status

The results of the study in the Cozie Alps Parks confirm that climate changes in the Alps favor Petronia petronia, ensuring a higher breeding success rate and average number of fledglings as well as a longer breeding period. At the same time, the progressive degradation of habitats due to the abandonment of traditional maintenance activities for alpine meadows does not seem to have consequences on the population dynamics of the Rock Sparrow.