It is not permissible to use live bait for fishing as this causes pain and suffering to the creature. (Fataawa Mahmoodiya vol.2 pg.397). Hadhrat ibn Umar (Radhiallaahu Anhu) narrates that Nabi (Sallallaahu Alayhi Wasallam) cursed the person who uses any living creature as a target. (Muslim vol.2 pg.153; Rashidiyyah).
And Allah Ta’ala Knows Best
Mufti Ebrahim Desai