The MINOS project examines whether large offshore wind energy plants in the German North and Baltic Seas impair or endanger harbour porpoises, seals or seabirds. The research results should make the necessary knowledge available, in order to be able to evaluate the future offshore wind park development. In the projects MINOS and MINOS+ - running time 2002 to 2008 - were therefore above all the preferential residence areas and migration routes of the endangered animal species investigated. Beyond that, hearing and acoustic sensitivity of harbour porpoises and seals were examined.