[ukmicky (OP)]

How do these amazing dolphins control these rings, why dont they simply go up

[DoctorBeaver]

If they're so clever how come they haven't learned not to follow tuna?

[ukmicky (OP)]

If you release a bubble of air into water it travels up,how is it that there rings of air dont  travel up.

P.S I didnt say they were clever

[RD]

The ring is a toroidal vortex (like a smoke ring): a doughnut of water is rotating around the air, trapping it.

The force created by the momentum of the rotating doughnut of water surrounding the air ring is greater than the buoyancy force of the air, so the air ring does not rise. 

[DoctorBeaver]

Excellent vid by the way

[neilep]

I love the video, and thanks for asking the question I was going to ask Michael..and thanks for answering it RD