An improved procedure to estimate wolf abundance using non-invasive genetic sampling and capture–recapture mixture models

摘要: Non-invasive genetic sampling (NGS) is increasingly used to estimate the abundance of rare or elusive species such as wolf (Canis lupus), which cannot be directly counted in forested mountain habitats. Wolf individual and familial home ranges are wide, potentially connected by long-range dispersers, their populations intrinsically open. Appropriate demo- graphic estimators needed, because assumptions homogeneous detection probability demographic closeness violated. We compiled capture-recapture record 418 genotypes identified from ca. 4,900 non-invasive samples, collected northern Italian Apennines January 2002 June 2009. analysed this dataset using novel multi- event models for open that explicitly account heterogeneity (IDH). Overall, weakly detectable individuals, probably pups, juveniles migrants (P = 0.08), was six times lower than highly wolves 0.44), adults dominants. The apparent annual survival rate individuals (U 0.66) those 0.75). population mean finite increase k 1.05 ± 0.11, size ranged N 117 2003 233 2007. This procedure, combining large-scale NGS multievent IDH models, provides first estimates abundance, multi-annual trend rates an large Apennines. These results contribute deepen our understanding ecology dynamics, provide new information implement sound long-term conservation plans.