A county wide eel research project was initiated by the Fisheries Agency of Japan in 1999. The primary objective of this project is to reveal the status of Japanese eels Anguilla japonica in freshwater habitats. Biological and environmental data are being collected from more than 15 rivers or lakes in 9 prefectures throughout the year. Two studies focused on; (l)development of stock management systems of glass eels; and (2)establishing eel stocking methods in selected rivers or estuaries. Monitoring of glass eel catch, release-recapture experiments and tracking of adult eel migration were conducted as the first step of these studies.