Hundreds of dolphins 'stampede' next to tour boat off California coast

Tourists on a whale watching tour watched in amazement as hundreds of dolphins raced alongside their boat.

Footage taken off the coast of Dana Point, California shows the dolphins jumping out of the water as swam past.

The behavior is what they call a dolphin stampede, when dolphins swiftly rise above the water's surface.

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Captain Dave's Dolphin and Whale Watching Safari captured the video, saying the dolphins behave this way because it's the "fastest mode of travel" with "less resistance in the air than in water."

They continued, “It is not known exactly what causes common dolphins to stampede. It’s thought that the dolphins could be evading a predator such as orcas, racing to catch a food source, or meeting up with another pod of dolphins.”