Tubenose goby – a discreet invader from the past goes higher

Abstract. The tubenose goby has been reported to be the first non-native postglacial gobiid immigrant from the Lower Danube refuges. It is thus a pioneer species that was the forerunner of the extensive invasion of Ponto-Caspian gobies that ascended the River Danube and spread across Europe a century before other goby species. It appears that recently the tubenose goby invasion has accelerated. In this paper historical data on the distribution of the tubenose goby, together with data from extensive monitoring of fish communities in Slovakia are examined to evaluate both the temporal and spatial aspects of tubenose goby distribution dynamics. Until the 1990s, the species was recorded only in the River Danube and small water bodies in the Danubian Lowland (Slovakia). Since then the tubenose goby has spread upstream into tributaries of the River Danube. It was also recorded in several streams in eastern Slovakia after 2014, and the spatial data demonstrate that the tubenose goby has been colonising new water bodies, progressing to the north and ascending rivers, reaching higher altitudes than previously reported. These findings suggest that the tubenose goby deserves attention, even after two centuries following the onset of its invasion, and its further expansion across Europe should be carefully monitored.