Visible crew/equipment: As Melanie drives up to have dinner at Mitch's, the reflection of the cameraman on the inside of the window can be seen moving in the upper-left hand portion of the screen. (00:32:10)
The Birds (1963)
Trailers
Directed by: Alfred Hitchcock
Starring: Jessica Tandy, Rod Taylor, Suzanne Pleshette, Tippi Hedren
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More mistakes in The Birds
Mitch Brenner: Aren't those lovebirds?
Melanie Daniels: No, those are, uh, red birds.
Mitch Brenner: Oh, I thought they were strawberry finches.
Melanie Daniels: Oh, yes. We call them that, too.
Trivia: When we see the school children running away from the birds, they were actually running on a treadmill with Bodega Bay footage added in the background.
Question: What's making the birds go insane and attack people?
Answer: None of the characters knew why the birds attacked, or the reason it was confined to the one town of Bodega Bay. The incident was so isolated that the outside news media was barely aware it was occurring or knew its severity, so there was no investigation into it at the time. Alfred Hitchc0ck's explanation was that the birds were rising up against humans to punish them for taking nature for granted.
Answer: It is never explained, probably because it would ruin the mystery of the film to spell it out.
If you are a Hitchcock fan, you pay attention to dialogue. They mention quite often that it started Melanie's arrival, of which she brought 2 caged birds. The rest is implied.