Changes in habitat selection patterns of the gray partridge Perdix perdix in relation to agricultural landscape dynamics over the past two decades

International audience; 1. Changes in agricultural practices have reshaped agricultural landscapes and triggereda drastic decline in spatial and temporal heterogeneity leading to changes inhabitat quality and food resources for birds. However, the precise relationshipsbetween landscape changes, spatial and temporal heterogeneity, and habitat preferencesin response to those changes remain poorly known.2. We investigated patterns of habitat selection and causes for changes over theyears 1997–2017 for the gray partridge Perdix perdix, an iconic farmland specieswhich has experienced a severe decline since the 1950s. Using a long‐term (1997–2017) dataset collected over 435 km2, we modeled relationships between annualland‐cover maps and partridge sightings over 17 5‐year moving windows, assessingthe effects of landscape metrics, the strength of the relationships, and thedynamics of habitat suitability.3. We detected a shift in gray partridge habitat preferences over time, toward morerisky habitats. Avoidance of predator reservoirs (woodlands and buildings) hasweakened, and selection of human infrastructure, such as roads and tracks, hasincreased. Since 1997, the mean size of suitable patches has also decreased byabout 26%.4. We have interpreted these changes in habitat selection as being the result of decreasinghabitat quality and the increasing prevalence of captive‐reared birds, currentlyreleased in their thousands in the study site.5. Synthesis and applications. The gray partridge has not adjusted well to changes infarming practices, and the low, still decreasing, population density suggests that itis not sustainable, despite local initiatives and the investment in captive‐bird releases.We emphasize that efforts must be redirected toward habitat improvementto restore the density of refuge cover, insects, and seeds in the landscape,hunting management to ensure self‐sustainable populations and massive releasesof high‐quality birds. Only integrated local management, involving hunters, farmers,gamekeepers, and scientists can ensure the recovery of this species.