Will mobs despawn when moved by water?

Question

I am working on a big project where I need to move mobs pretty far using a water system. They wont see light at all.

Will they despawn after some time?

Im guessing the tour will take about 3-4 mins.

Answer 1

It depends if the following conditions are met:

Monsters and squid (but not animals) can spontaneously cease to exist, or "despawn", under certain conditions:

• A mob will immediately despawn if ever there is no player within 128 blocks of it.
• A mob that has had no player within 32 blocks of it for more than 30 seconds has a 1 in 800 chance of despawning on each game tick (1/20th of a second). That means that such a mob will survive for just under a minute, on average, from the time they spawned or were last within 32 blocks of a player.
• All hostile mobs in a world will despawn if the difficulty is set to peaceful, regardless as to where the player is positioned in the world.

In multiplayer, despawning does not occur while there are no players in the game.

Answer 2

Short answer: No
Long Answer: Maybe, depending on where you are.

Mobs Despawn when they are a certain distance from the player, so if the water moves them far enough away from you, then yes they will despawn. The Minecraft Wiki states that:

• A mob will immediately despawn if ever there is no player within 128 blocks of it.
• A mob that has had no player within 32 blocks of it for more than 30 seconds has a 1 in 800 chance of despawning on each game tick (1/20th of a second). That means that such a mob will survive for just under a minute, on average, from the time they spawned or were last within 32 blocks of a player.

Answer 3

The probability of survival for a mob with a player in 32 - 128 blocks distance for 3 minutes is around 1%. Just did the math assuming despawn occurence independence.