Distribution of introduced American mink in the Northern Apennine area (Central Italy)

The American mink Neovison vison is a widespread alien carnivore in Europe due to escapes from fur farms through this continent. Impacts by naturalized mink include competition with native species and predation of crayfish and small vertebrates. Therefore, an updated monitoring of mink distribution is required to design management plans. The American mink has been reported with an established population in North-Eastern Italy, in Sardinia, and two small nuclei respectively in the Central and in the Northern Apennine ridge. Available information for the latter dates back to early 1990s. In this note, we described the range expansion of the American mink population in the Northern Apennine ridge and we estimate the current distribution range and the extent of occurrence by using data collected from 2006 to 2021 through the Minimum Convex Polygon (MCP). We compared the current distribution range with that of 1990s. The American mink showed a remarkable range increase since its first escape in the Northern Apennines, thus requiring rapid actions to limit impacts on native biodiversity.

How Raccoons Could Lead to the Disappearance of Native Crayfish in Central Italy

The white-clawed crayfish Austropotamobius pallipes complex populations are decreasing in the Foreste Casentinesi, Monte Falterona and Campigna National Park (Central Italy), due to several factors, including illegal poaching, predatory fishes, drought, and invasive alien species. Recently, the Northern raccoon Procyon lotor has been reported to be present in the area of the National Park and has started to predate on the white-clawed crayfish. The aim of the study was to update the distribution and population status of A. pallipes in the reserves, other sites of the National Park, and surrounding areas to assess the potential effects of the raccoon. Crayfish were sampled by hand or by traps in 14 sites; sampled individuals were sexed and measured. Signs of raccoon presence (e.g., footprints and predated crayfish) were also recorded. Our study confirms the impact of raccoon on native crayfish: indeed, where the invasive mammal is present (six sites), crayfish disappeared, or their populations have been dramatically reduced in number, with a size distribution skewed towards juveniles. In two sites, close to urban settlements, fresh footprints of P. lotor and predated specimens of A. pallipes were also observed. Populations of crayfish are still abundant or even increasing as compared with samplings conducted in the past where raccoon is absent (five sites). Urgent actions (e.g., control of raccoons, and monitoring and restocking of A. pallipes populations if feasible and where possible) should be taken into account to guarantee the survival of this protected species.

Time is running out! Rapid range expansion of the invasive northern raccoon in central Italy

The northern raccoon, Procyon lotor (Linnaeus, 1758), is listed among the invasive alien species of European Union concern. Therefore, an updated monitoring of its distribution is required to design and address management actions. As to Italy, the raccoon has been reported with an established population only in northern regions. In this note, we report a new established raccoon population along the Apennine ridge in central Italy and we estimate the range expansion from 2015 to 2018 both through the minimum convex polygon (MCP) and the kernel estimates. Furthermore, we propose the management actions to limit negative impacts in the Foreste Casentinesi National Park and its surroundings.