This species has been nicknamed the “killer shrimp” for its extremely aggressive behaviour towards native invertebrate species. Due to their large body size and well developed mouthparts, killer shrimp are effective predators, which kill or simply bite off much more prey than they can consume (Dick et al., 2002).
In all the European aquatic systems where it has become established, D. villosus has largely replaced both indigenous and exotic amphipod species (Kelleher et al. 1999). In addition, this species readily consumes fish eggs (Casselato et al. 2007) and even attacks fish larvae (Schmidt and Josens, 2004). Due to its predatory activities, D. villosus significantly changes natural food webs of invaded ecosystems and occupies high trophic levels comparable to fish (Van Riel et al. 2006).