Bell Tail Monster.

This creature migrates from one side of the world to other when its mating season. When they reach their destination they take their tails out of the water and make them toll, the sound resonating for miles around.

Link to the Model in Sketchfab.

https://sketchfab.com/3d-models/bell-tail-acuatic-monster-83ad51f618634047b1c1f08866f64ecd