All schools of Islamic thought agree that all types of fish living in the sea are halal. This is based on the Quran, which states: “Lawful to you is the game of the sea and its food, as provision for you and for travelers” (Surah Al-Ma’idah, 5:96). Another verse says, “The two seas are not alike: one is fresh and sweet, the other salty and bitter. But from both, you eat fresh tender meat” (Surah Fatir, 35:12).
Thus, besides commonly consumed fish, it is also permissible to eat whale, dolphin, shark, and other fish types.