Practitioners of leisure activities can prevent invasive species in coastal waters and estuaries!

Due to an increased international trade and maritime traffic between Europe and the world, the amount of invasive non-native species (INS) in the seas and estuaries has increased enormously. INS can either enter our estuaries by import or by ‘stealing a ride’ (e.g. ships). Non-native species can be imported for commercial or decorative purposes, but can escape from aquaculture companies or aquaria. Sometimes INS can be hidden in imported gravel or sand. Hitch-hiking of species in ballast water or on the hull of industrial ships or recreant vessels are reasons why estuaries are hotspots of INS.

It is common sense that these non-native species can cause damage to the environment or economy. According to the European project Safeguarding the Environment From Invasive Non-Native Species (SEFINS), it is clear that (at a global level) INS is one of the most important causes for the loss of biodiversity. For example, the Japanese shore crab (Hemigrapsus sanguineus), originating from the western Pacific Ocean, is a little non-native species that reduces the amount of native crab populations due to competition and predation. The Japanese shore crab eats larvae and juveniles of native snail, barnacle and polychaete species. Also oyster- and mussel beds can be damaged by the activity of this non-native crab. As a consequence, INS can be responsible for the loss of millions of euros because of the overgrowth on boats and estuaries, and damaged fishery.

What to do to prevent IUS? You can read all about it in the flyer available in English, Dutch and French . Clean the hull of your vessel on a regular basis and recognize the non-native species. Using the free App ‘That’s Invasive!’ you can help RINSE in order to get an overview of the amount and locations of the IUS by signing in the observed species. This App is available for iPhone and Android. Look out for living organisms on your equipment, clean your equipment nicely and let it dry (several species can survive days in a humid environment). And at last, spread the word! Tell your fellow sailors, fishers, divers, surfers or owners of yacht (clubs) about the danger and consequences of INS.
 
Earlier in 2014, the SEFINS-project has published the publication ‘Safeguarding the Environment from Invasive Non-native Species’ (available in English, Dutch and French). Since the new EU directive concerning INS, EU-members must prepare themselves for these coming-up species using these publications.