Your attention, please: The mystery at the heart of Alfred Hitchcock's 1963 horror film The Birds has been solved in the comments section of a website. Below, a video posted by Richmond District Blog shows an untold number of gulls swarming for seemingly no reason, affected much like those in the Bodega Bay of the film. Observe:

“There was a crazy seagull feeding frenzy today at Sutro Baths/Seal Rocks," the woman who took the video told Richmond District Blog. "No idea what was in the water, but never seen anything quite like it there."

One commenter, however, has hit upon the solution, and by extension, the logical explanation to the Hitchcock film:

"It’s herring," writes commenter RIP. "The 13 spawn events happened around the bay area but usually finish around mid-March. However, because of surface temperature of water they crowd up next to beaches and shallow areas after the spawn. Sometimes sea lions drive them into large groups and they move towards the shore to escape, where the seagulls are waiting."

There you have it. Hitchcock's birds were just crazy for herring. So obvious.

Commenters, now's your chance. Anyone have any theories about the Zodiac killer?

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