Playful dolphins pull on manta ray's tail to play with scuba divers

This video was taken at Socorro off the cost of Mexico in the Pacific. A single pod of dolphin (maybe 12 individuals) wanted to check out the scuba divers. The two dolphins in the video appear to be playing with (teasing) the manta ray. They seemed to enjoy it. Dolphin are very intelligent animals, maybe second to man. They must get bored too, because it sure appears that the divers in the video were their entertainment as well. After the dolphin leave, the manta ray returns!