Red-billed chough (Pyrrhocorax pyrrhocorax) models

The absence of a species in apparently suitable regions is often attributed to habitat deterioration, which, according to the IUCN-guidelines, would preclude reintroduction unless the habitat is sufficiently restored. The crux is therefore to determine species’ key habitat requisites and to localize potentially restorable sites based on the habitat selection of thriving populations in similar environments. The distribution of the Red-billed chough (Pyrrhocorax pyrrhocorax) in the Alpine arch is currently restricted to its western side. The eastern Alps have only been occupied sporadically during past centuries, which triggered a discussion around reintroduction. The fact that the last confirmed pairs bred at middle elevation, in derelict buildings instead of alpine cliffs, suggested a lack of habitat suitability in the uplands. To test this hypothesis, we modelled seasonal foraging habitat (during winter, breeding and dispersal) and nest site-selection in the western Swiss Alps using lo...