Noninvasive molecular tracking of colonizing wolf (Canis lupus) packs in the western Italian Alps


  • This research was conducted at the Conservation Genetics laboratory at Italian Institute of Wildlife Biology (INFS), and it is part of an ongoing project on wolf recolonization of the western Alps (Progetto Lupo Interreg, Regione Piemonte). V. Lucchini and E. Fabbri are, respectively, researcher and PhD fellow at INFS and University of Ferrara. This work is part of the PhD thesis by F. Marucco and S. Ricci under the supervision of Prof Luigi Boitani, University of Rome. E. Randi is head of Conservation Biology and Genetics at INFS.

Ettore Randi. Fax: 39 051 796 628; E-mail:


We used noninvasive methods to obtain genetic and demographic data on the wolf packs (Canis lupus), which are now recolonizing the Alps, a century after their eradication. DNA samples, extracted from presumed wolf scats collected in the western Italian Alps (Piemonte), were genotyped to determine species and sex by sequencing parts of the mitochondrial DNA (mtDNA) control-region and ZFX/ZFY genes. Individual genotypes were identified by multilocus microsatellite analyses using a multiple tubes polymerase chain reaction (PCR). The performance of the laboratory protocols was affected by the age of samples. The quality of excremental DNA extracts was higher in samples freshly collected on snow in winter than in samples that were older or collected during summer. Preliminary mtDNA screening of all samples allowed species identification and was a good predictor of further PCR performances. Wolf, and not prey, DNA targets were preferentially amplified. Allelic dropout occurred more frequently than false alleles, but the probability of false homozygote determinations was always < 0.001. A panel of six to nine microsatellites would allow identification of individual wolf genotypes, also whether related, with a probability of identity of < 0.015. Genealogical relationships among individuals could be determined reliably if the number of candidate parents was 6–8, and most of them had been sampled and correctly genotyped. Genetic data indicate that colonizing Alpine wolves originate exclusively from the Italian source population and retain a high proportion of its genetic diversity. Spatial and temporal locations of individual genotypes, and kinship analyses, suggest that two distinct packs of closely related wolves, plus some unrelated individuals, ranged in the study areas. This is in agreement with field observations.