That may be a fake(don't know)but years ago we surfed a place that was a regular shark area.
Not being the best of surfers I was the first one back to the beach. From there I saw the shapes in the waves and heard the guys yelling.
There were 3 dolphins surfing as well as the guys.
When we all realised what they were the others went back into the water and surfed with them. One guy would get on the wave and at least one dolphin would join him on the wave.
I sat on the beach and got as much enjoyment watching as the guys in the water did. The dolphins stayed for about an hour but I mean,they were SURFING

Mt Greenly,out of Coffin Bay,South Australia,1973.
Cheers
White on White fly all night.
Red on White you're alright.
Red on Red you'll soon be dead.