Opportunistic alien catfish: unexpected findings in the diet of the alien species Ictalurus punctatus in Central Italy

摘要

Alien fish species are known for the negative impacts they can have on native species and their ability to shape recipient communities. One such case is the North American channel catfish, Ictalurus punctatus (Raf.), in the Arno River in central Italy. During river bank reconstruction, specimens of this species (n=40) were collected, and the stomach content was analysed. As a result, we highlight the opportunistic feeding behavior of this alien species that is responding rapidly to newly available resources and also poses a threat to native species.