Minecraft wiki entry for Fishing_Rod, associated text: In Java Edition, the drowned mob has a 3.75% chance of spawning with a fishing rod equipped. In Bedrock Edition, naturally-spawned drowned has 0.85% chance to spawn with fishing rod, while converted drowned has 1% chance to spawn with it. If killed, they have an 8.5% chance of dropping this fishing rod. That chance increases by 1% for each level of Looting applied to a weapon (up to 11.5% chance). The dropped item is damaged and never enchanted.