Fish and dolphins disappeared

@[Mod] Neko You marked this issue as resolved due to a duplicate, but mention a duplicate from snapshot 7 with a different issue. There are no fish or dolphins in any of the oceans in my world.

Please reopen this issue.

Not sure what you are referring to.

5 days, all the dolphins and fish in the oceans and rivers have disappeared

This is intended behavior. Dolphins and fish despawn.

Fish I caught with a bucket and put in my aquarium are still there.

This is also intended behavior. Fish picked up and placed by buckets will not despawn.

Then are they not supposed to respawn? I highly doubt that they went through the effort of creating all these types of fish only to have them despawn and then not respawn again.

They do eventually. Though I think that depends on other entities in the area.

For 2 days, we have not seen a single fish. I went with a boat through the ocean for about 7500 blocks and then back again, cleared monuments etc unde rwater, not a single fish anywhere. 

Create a new report with the world download.