Hey @caosck,
Thank you for reporting this and sorry to hear you experience this in game.
The video you provided is very helpful.
If you haven't already would it be possible to follow our PC troubleshooting guide in full?
Many thanks
Thank you for the video and location @caosck
This issue has been reported before but not in this location, so I have added your video to our investigation, thank you.
I believe it is a bug as you say. If you moved the camera around in the game, did the flying fish disappear temporarily, permanently, or not at all?
Did you happen to encounter this bug again, if you fast travelled out of the area, then returned to the same exact spot?
I'm glad to see our scaly friends were not harmed in the making of this video caosck.
I will keep my eyes peeled for more reports of this and videos, as at the moment this is still under investigation, it has been hard to reproduce, as it seems to happen at random, at random places on the map 
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