Dolphins don't consistently jump out to breathe, so they always die after a few minutes

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my dolphins are still dying in fact, sometimes they cannot crawl and get into the water and they die this error had i been reported long before this user and had generated another report because they required it but they marked it as duplicate

Related issues: MCPE-32630, MCPE-33707, MCPE-44918, MCPE-59701

I believe some dolphins are able to jump out of water, and some just aren't able to, despite having access to air.

Also in 1.16.0.63 they donot fix that

I confirm at 1.16.0.64 it continues passing 9 out of 10 dolphins do not return to the water

Affects 1.16.0.66

Affects 1.16.0.67

Affects 1.16.0.68☹

Confirmed for 1.16.0

confirmed for 1.16.1

Confirmed for beta 1.16.20.53

Confirmed for 1.16.100.54.

it's annoying as dolphinariums become so impossible. Even leashed on the surface of the water only helps for a while.

Affects 1.17.40.21
Affects 1.17.30

Can confirm for 1.18.10.26

Affects 1.19.0.28/29 beta and preview

can confirm for 1.19.51

in beta 1.19.60.24, dolphins will only jump into the air if you are riding a boat and they are following you. but they are supposed to jump for air every four minutes or so regardless of the players actions

This happens in 1.19.71. I attached a video.

The entire pool is filled with source blocks. There is no flowing water.

Still happens in the most recent version 1.19.81

Testing in 1.20.12 Hotfix, dolphins do jump out of water to breath every 4 minutes most of the time. It does not matter if I spawn them on land or in water, or pull them out of the water for a little while after spawning them in water. I recorded one coming up to breath every 4 minutes 3 times in a row, even. However, when I afk at a dolphin pool for longer periods of time and come back, they are always gone.

New duplicate report MCPE-180897 includes a video clip of a dolphin dying because it does not reach the surface to breath: https://bugs.mojang.com/secure/attachment/569423/video_20240424_190709.mp4

In this video the dolphin tries to breach the surface but stops a block or two below where it should and swims in circles, as if it cannot find the surface. This seems to match the behavior partially captured in the video attached to this ticket.

Update 3/6/25: the real cause of this issue is MCPE-190996, contrary to my earlier analysis below, which I have crossed out.

Update: after extensive testing based on the above lead, I can confirm that this bug has the same cause as MCPE-45645, MCPE-131091, and MCPE-162241: when mobs swim, the position that they target for movement is offset in the -Y direction from the path that they have pre-generated. In other words, after they find a path through water they try to move a block below that path. The exact offset is difficulty to determine; I think it is between 0.25 and 1.25 blocks.

This offset causes dolphins to stop below the surface of the water when they come up to breath (using behavior.random_breach). I believe they only successfully breach the water surface if they happen to run the behavior when they are already very close to the surface (within about 2 blocks).

shows dolphins repeatedly swimming up toward the surface and stopping.

contains the dolphin test chamber and several others that can be used to investigate this bug.

Can’t believe how long it takes to resolve an issue like this,,,, still happening in 1.21.1

this happening in 1.21.90