Functional diversity of the Middle-Danubian fish fauna, the role of non-native species

It is well known that physical appearance and behavior of each species reflects to its habitat preference, feeding habits, etc. Therefore, one can describe the ecological role of species in a community by characterizing their life-history and functional traits. By applying this framework across all species present in the community, we can characterize its funcitonal diversity. The Middle-Danubian hydrosystem is characterised by valuable and diverse fish fauna, at the same time this area is highly exposed to the invasions because of the „natural" range expansion of Pontos-Caspic species and due to the illegal fish stockings. And although several notes deal with the effect of non-native speci…