Mapping and explaining wolf recolonization in France using dynamic occupancy models and opportunistic data

• DOI: 10.1111/ecog.02874
• Publication Date: 2017-05-16T10:03:05Z
• Authors: Julie Louvrier; Christophe Duchamp; Valentin Lauret; Eric Marboutin; Sarah Cubaynes; Rémi Choquet; Christian Miquel; Olivier Gimenez
• Keywords: Occupancy; Species distribution; Sampling bias

While large carnivores are recovering in Europe, assessing their distributions can help to predict and mitigate conflicts with human activities. Because they highly mobile, elusive live at very low density, modeling presents several challenges due 1) imperfect detectability, 2) dynamic ranges over time 3) monitoring scales consisting mainly of opportunistic data without a formal measure the sampling effort. Here, we focused on wolves Canis lupus that have been recolonizing France since early 1990s. We evaluated effort posteriori as number observers present per year cell based location professional then assessed wolf range dynamics from 1994 2016, while accounting for species detection time‐ space‐varying using site‐occupancy models. Ignoring effect detectability led underestimating occupied sites by more than 50% average. Colonization appeared be negatively influenced proportion site an altitude higher 2500 m positively observed short long‐distances, forest cover, farmland cover mean altitude. The expansion rate, defined given divided previous year, decreased first years study, remained stable 2000 2016. Our work shows analyzed distribution models control detection, pending quantification approach has potential being used decision‐makers target where likely occur conflicts.