Changes in agricultural practices have reshaped agricultural landscapes. They have triggered a drastic decline of spatial and temporal heterogeneity leading to changes in habitat quality and food resources for birds. Consequently, a severe decline in European farmland birds has been observed during the last decades. As studies that have demonstrated changes in habitat selection in response to land cover variation are rare in birds, we investigated whether, and if so, how habitat selection patterns have varied over the last 20 years in Grey partridge, an iconic farmland species, which has experienced a severe decline since the 1950s.
We used a long-term (1997-2017) dataset on Grey partridge occurrences collected in the Long-Term Socio Ecological Research platform (LSTER) “Zone Atelier Plaine & Val de Sèvre”, Western France. We investigated changes of land cover across years running species distribution models. We assessed the dynamic of landscape metrics' contributions, the strength of the relationship between landscape features and partridge occurrence, and the dynamic of habitat quality over time.
Our results suggest that over time, Grey partridge occurrence has become less influenced by the distance to predator reserves (woodlands and urban areas) and more by permanent landscape covers (i.e. road/pathway and hedgerows densities). We discuss the shift of habitat selection with the change in the size and quality of suitable patches.