Schwarzmundgrundel & Co. : Fremde Fische in Flüssen und Seen

The number of non-native fish species in our water bodies isincreasing in the course of globalisation. They navigate artificial canals, travel in ballast water of ships or are displaced as eggs attached to ships and other materials. Many of these species remain unnoticed but some may establish a reproductive population and even cause harm. Invasive gobies from the Black Sea – especially the bighead goby and round goby – are taken as an example to explain how biology andecology can be studied and how we proceed to estimate the potential risk. Simple egg traps may help to reduce dispersal of these fish. Such measures are especially promising at locations such as the Upper Rhine where hydropower dams present bottlenecks.