Local movements and population size of european eels, Anguilla anguilla, in a small lake in southwestern Spain

Radio telemetry was used to study the movements of European eels, Anguilla anguilla , in a small (1.2 ha) lake in southwestern Spain in March and April, 1985. Eels covered a larger area at night than during the day, with an average of 23% and 42% of the activity region used during the day and night respectively. Average distance moved between observations was significantly greater at night than in the day. Eels tracked during rainy and cloudy weather were more active during the day.