Assessing range re-expansion and recolonization of human-impacted landscapes by threatened species: a case study of the otter (Lutra lutra) in Italy

摘要: Detecting and understanding recoveries of threatened species from past recent presence/absence data is essential to improving conservation efforts. However, false positive trends may be reported because absences in data, therefore appropriate testing needed. We tested an expansion/recolonization the otter (Lutra lutra) populations Italy a fragmented distribution outlined 1984-1985 period by using Monte Carlo simulations. Land-use changes, human depopulation decrease influence anthropogenic features were investigated as potential drivers recolonization GIS modeling. A survey entire Italian range otter, conducted 2002-2004, recorded 2.2-fold increase proportion occupied 10-km squares 49 local colonizations. The size urban land-use smaller (P < 0.05) than those derived simulated surveys based on random versus colonization events. expanded southward nearly reached southern margins peninsula. Recolonization moderately urbanized landscapes was not accompanied depopulation. According partial logistic regressions, pure effect land industry proximity occurrence probability declined about 48%, suggesting decreased impact stream habitat. Conversely, natural factors, increased importance 116%. absence significant northward expansion 20 year suggests that habitat restoration should planned encourage further recolonization. On other hand, threats newly controlled.