De aal: portret van een uistervende globetrotter

European eel: Portrait of a globetrotter threatened with extinction. This article summarises the state-ofthe- art knowledge on the European eel (Anguilla anguilla L.). There is growing concern about the future of the species: population data reveal a strong decline since 1980. This decline is probably due to a combination of anthropogenically induced factors. Several measures, both short term and long term, are needed for improvement of the habitat and restoration of the population. It is essential that the mortality caused by the turbines of hydropower plants, pumping engines, and the over-exploitation of the species by the fisheries is minimised. Recovery will take at least more decennia. Therefore, strong and continuing support for these measures is needed at all levels, with an increase in social awareness and political attention. A restoration initiative was set up in the Netherlands in 2009 (projectgroep Aalherstel), aiming to initiate and stimulate activities that contribute to the protection of the eel in Dutch waters, and a sustainable population in the long term.