We prepare an updated account of the distribution of the swimbladder parasite Anguillicola in Flemish eel populations, which will be put in an European perspective. The swimbladder of 1200 European eel will be screened for the presence of the various stages of the parasite. The prevalence and intendity of the infection will be calculated and the results will be discussed in view of previous results. Assistance for mapping, know-how and reporting will be provided by the Institute of Forestry and Wildlife Management.