A miles-long cluster of dolphins has been filmed leaping and gliding across Carmel Bay off California, forming an unusual “super pod” of more than 1,500 of the marine creatures.

Monterey Bay Whale Watch said more than 1,500 dolphins were spotted by the company's scouting boat when it went out to perform a survey.

Over 1,500 Risso's dolphins formed a rare super pod off Carmel Bay, California, stunning marine biologists as they stretched for miles, leaping and gliding.