Allarme rosso: espansione della storica invasiva Procambarus clarkii (Girard, 1852) nei laghi Pistono, San Michele e Sirio.

Following extensive monitoring of lacustrine ecosystems in Piedmont (Italy), this study analyses the ongoing expansion of the red swamp crayfish Procambarus clarkii within lakes Pistono, San Michele, and Sirio. We characterized the occurrence of the species in relation to habitat typology and hydrochemical parameters. Utilizing baited traps, 44 and 39 P. clarkii were caught respectively in Lake San Michele and in Lake Pistono, whereas only 4 individuals were captured in Lake Sirio. Correlation analyses between environmental variables and relative abundance revealed the species’ preference for reed beds, where higher abundances were observed compared to lake shores. Our results highlighted the urgent need to implement monitoring and management programs to prevent the further dispersal of P. clarkii in the region and to mitigate adverse ecological impacts, particularly within protected sites of the Natura 2000 network.