A risk assessment of biological invasions in the inland waterways of Europe: the Northern Invasion Corridor case study

Inland waterways have provided opportunities for the spread of aquatic non-indigenous species (NIS) for many centuries (reviewed in Ketelaars 2004, Galil and Minchin 2006, Galil et al. 2007). Canals connecting different river basins have allowed for range extensions of many species, either by active movement and/or by ship transport. Over the past century, the potential for species to expand their range has been enhanced due to increasing trade and the construction of canals. The waterways occur at low altitudes and presently the main European corridor routes consist of an interlinked network of 30 main canals with more than 100 branches, and more than 350 ports exist in low-altitude Europe.