First record of the round goby Neogobius melanostomus (Pallas, 1814) in the lower River Oder, Germany

In September 2013, the non-native round goby Neogobius melanostomus was found for the first time in the River Oder, Germany, about 58 km upstream of the Szczecin Lagoon (Zalew Szczecinski). Seven specimens were caught at river kilometre 703.5 near Friedrichsthal (53°08'24.29"N, 14°23'03.59"E) during the regular fish monitoring program for the Water Framework Directive. This record is especially important because i) it represents a very early stage of the invasion process, a round goby invasion front, and ii) it potentially reflects the natural dispersal ability of the species. The latter was concluded from the time lag of about 15 years between the first occurrence of round goby in the Baltic Sea in front of the River Oder estuary in 1998, in the German part of the Szczecin Lagoon (River Oder estuary) in 2003, its subsequent establishment in the Szczecin Lagoon in 2006, and its upstream migration observed in 2013. The slow average migration speed of 3.9 km per year might correspond to natural dispersal.