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Copyright of Archeologia Medievale: Cultura Materiale, Insediamenti, Territorio is the property of All'Insegna del Giglio s.a.s. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rock ptarmigan populations in the Alps are suffering an overall decline, and management actions are needed to ensure their conservation. Yet wildlife management and conservation actions are often the consequences of political decisions taken by subjects that lack the scientific knowledge about the relationships between the environment and species ecology. Habitat suitability models are tools that translate these complex relationships into mathematical models and spatially explicit maps of potential presence and abundance of species that are easier to understand by people not experienced with the study of biological processes. In this study, I modelled the species-habitat relationships at two levels, by estimating the potential distribution and potential density of the species in a protected area of the Western Italian Alps. In particular, I took the results of a previous study carried out in the same area to estimate the probability of male occurrence by comparing the habitat structure in presence plots and random plots, respectively, by logistic regression analyses. Then, I applied the logistic regression equation to the same variables measured in hexagonal cells of a grid superimposed over the entire study area, and I obtained the map of the potential distribution of the species. Finally, I developed multiple regression analyses of male density estimated by distance sampling vs habitat variables, and I applied the results to the areas of potential distribution to forecast the potential density and therefore the carrying capacity of the study area. I obtained a potential distribution of 38.2 km2, with a potential average density of 5.1 males/km2. The latter was positively affected by the percentage cover of grassland and rocky grassland in the plots. The integrated approach that I used by combining models of occurrence and density allowed me to confirm and improve the results of previous works on rock ptarmigan predicted occurrence, to identify areas of conservation importance within the protected area and to give useful tools for spatially explicit management to the Natural Park administrators. [ABSTRACT FROM AUTHOR]