Studies of the Eel Anguila Anguila in Ireland No. 3. In the Shannon Catchment

Abstract

A sample of 1,637 immature eels of length 28 to 91 em and age 5 to 26 years was collected in summer seasons from 1969 to 1973 by fyke netting. The growth rate was similar to that of eels in many other Irish lakes but the age at maturity in the eels of the main Shannon was several years more than in similar waters. The food was almost exclusively invertebrate. In the Fergus system lakes earlier maturity was noted and fish was the principal food of eels of over 50 cm. A preliminary study of eels migrating upstream at Parteen Weir in 1973, 15 km above the tidal boundary, showed that few, if any, elvers travelled that distance in their first year.