NEWPORT BEACH, Calif. (KSWB) — A huge pod of dolphins swam alongside a whale watching boat off the coast of Southern California on Sunday, awing passengers lucky enough to witness the sight in person.

The “stampede,” as the team at Newport Landing Whale Watching called it, happened near Newport Beach. Giddy passengers held up their phones to record videos and a crew member speaking over a loudspeaker stopped to chuckle in disbelief. A long row of dolphins surged forward in unison, extending into the distance. The scene was striking and the timing was perfect: just before sunset, at the coveted “golden hour.”

Dolphin stampedes are also sometimes referred to as “super pods” or “megapods.” As the American Cetacean Society explains, common dolphins such as the ones seen Sunday typically travel and hunt in large herds of hundreds or even thousands.

The reason why a large pod would start moving so quickly together isn’t always clear, but as one expert explained, the dolphins can actually move faster by repeatedly leaping into the air. That behavior is called “porpoising.”

“We don’t know exactly what causes common dolphins to stampede, but it’s thought that the dolphins could be evading a predator, or they might be catching up to a food source,” explained Jessica Roame, who leads educational programs at the whale watching company.

“Porpoising out of the water at a high rate of speed is the fastest mode of travel for dolphins because there is less resistance in the air than in water, which is why these dolphins move in this way when they’re in a hurry, and when hundreds of dolphin do this together, we call this a stampede.”

Roame said Sunday’s super pod was the largest that the company’s captains have seen in years: “Easily thousands of animals!” she wrote in an email about the encounter.

Newport Landing is based in Newport Beach and books year-round whale watching tours through its website. The American Cetacean Society, of which Roame is a member, is a conservation group with educational resources for those interested in learning more about marine mammals.