There are two main angling venues on the Shannon in the immediate Limerick area.
These are on the Maigue River at Annacotty (5 kms) from Limerick and Plassey on the Shannon in the University of Limerick (UL) Campus - near Castletroy, on the outskirts of Limerick City.
Because of poor access this section is under fished but can produce very good fishing if the effort is put in and the angler is prepared to explore and experiment.
Angling from a boat for any kind of fish is prohibited in that section of the Lower River Shannon from Plassey Bridge adjoining the townlands of Sreelane in Co. Clare and Garraun in Co. Limerick to Thomond Bridge in the city of Limerick during the period commencing 1 March and ending on 30 September in any year.
Reference: http://www.fishinginireland.info/pike/shannon/limerick.htm