Impacts Analysis of Alien Macroinvertebrate Species in the Hydrographic System of a Subalpine Lake on the Italian-Swiss Border

The potential invasiveness of alien macroinvertebrate species in the Italian/Swiss hydrographic system of Lake Maggiore (NW Italy) was assessed through the Aquatic Species Invasiveness Screening Kit, a risk assessment tool developed for quantifying the impacts of alien species on the commercial, environmental, and species traits sectors. Data were collected using the databases provided by two regional environmental agencies in northern Italy (Lombardy and Piedmont regions) and by the governmental monitoring program of Switzerland, which were integrated with a systematic literature search on Google scholar and ISI Web of Science. In the assessment area, 16 macroinvertebrate invasive alien species were reported: nine mollusks, four decapods, and three amphipods. The species assessment indicated seven species with a high level of invasiveness: Procambarus clarkii, Faxonius limosus (formerly, Orconectes limosus) and Pacifastacus leniusculus, Dreissena polymorpha, Corbicula fluminea, Sinanodonta woodiana, and Pseudosuccinea columella. The results allow invasive species managers to understand which species to focus their monitoring on in the near future in order to track IAS movements and limit their spread within the hydrographic system and to provide the identification and refinement of concerted bilateral strategies aimed at limiting the impacts of these species. They also account for the implications of future climate change on the invasion potential of each species.