• Distribution, status and recent population dynamics of Alpine ibex Capra ibex in Europe

      Brambillla, Alice; von Hardenberg, Achaz; Nelli, Luca; Bassano, Bruno; University of Zurich, University of Chester, University of Glasgow, Gran Paradiso National PArk (Wiley, 2020-04-20)
      1. Despite its recent successful and well-documented reintroduction history, a comprehensive and current update of the distribution and status of the Alpine ibex Capra ibex is lacking. As some concerns persist about its conservation, a status update appears essential for future conservation and management strategies on a large scale. 2. We provide an exhaustive update of the geographic range of the species, alongside estimates of its current abundance and population trends from 2004 to 2015. 3. We gathered census and distribution data for all the Alpine ibex colonies from management authorities and research groups that monitor them in different countries, and from the literature and publicly available reports. We produced a distribution map, reported the number of individuals observed in the most recent censuses, and estimated global, national, and local population trends using Bayesian hierarchical models. 4. Our model estimated that there were a total of 55297 Alpine ibex in the Alps in 2015 (lower 95% Credible Interval [CrI]: 51157; upper 95% CrI: 62710). The total number of individuals appears to have increased slightly over the last 10 years from the 47000-51000 estimated in previous reports. Positive population trends were observed in Switzerland and Italy, while no trend was apparent in France. For Austria, Germany, and Slovenia, there were insufficient data to estimate a trend. The slopes of the colonies’ trends were positively correlated with the year of colony foundation. 5. The geographic range of the Alpine ibex does not seem to have increased in size in recent years, although the accuracy of the spatial data varies among countries. 6. The periodic and standardised collection of census data for all colonies and a common policy of data-sharing at a European level appear essential for monitoring the global trend of this species and for planning balanced conservation and management actions.