European wildlife is always subject to change. Species disappear and evolve, but new species can appear and colonize, mostly due to accidental introduction by humans. For example, the construction of the Rhine-Main-Danube Canal has led to an dramatic increase in exotic macrofauna and gobies (fish) in Dutch waters. New species can also hitch a ride to Europe on shipping vessels from America and elsewhere.

The dangers of invasive non-native species can be illustrated by the fungus brought in with alien crayfish, which has almost wiped out native crayfish in the Netherlands. Poisonous plants, such as giant hogweed and common ragweed, cause a serious nuisance to people. A European Regulation on Invasive Alien Species, which states that member states must take measures to tackle non-native species, has been in force since 2015 and underlines the urgency of the problem.

Waardenburg Ecology has discovered a number of new non-native species during monitoring programmes in brackish waters and in the North Sea in recent years. We advise regional and local authorities on policies relating to non-natives, such as non-native crayfish, and can survey for their presence. We work together with organisations such as the Netherlands Expertise Centre Exotics (NEC-E), and have recently produced a horizon scanning document of non-natives that may end up in the Netherlands.