They posted their video Saturday on YouTube with the title "Whales almost eat divers," The (San Luis Obispo) Tribune reported. Shawn Stamback and Francis Antigua, both residents of San Luis Obispo, Jay Hebrard of Atascadero and Jeremy Bonnett of San Diego had their close encounter Saturday morning more than 2 miles from the shore.
Stamback said he and Antigua took a break after their first dive by snorkeling.
"Before I knew it, a big boil of bait fish started shooting up in my face," Stamback recalled. "As soon as that happened, I knew exactly what was going on. I knew there was a predator chasing those fish. I had no idea there was a freaking freight train behind those fishies. That really blew my mind."
The next thing they knew, two large humpbacks, both weighing many tons each, breached and then disappeared back into the ocean with mouthfuls of food.
After that, the group decided not to go on a second dive because they had probably used up their luck.
But Stamback is still glad of the experience: "I got to experience something on Earth that very few people have."