What you want to feed them are a few Alka-Selzers.
They can't burp. You'll see red from their exploded crop in an hour.
I had my own run-ins with the critters at Presidio of Monterey doing repairs to a clinic. These are the most hateful creatures in the world once they are after you. I required stitches on my temple due to an attack. Happy to see them dead.
Crows are pretty heinous, too. I confess to having shot crows.........bagged 'em, took 'em for a midnight ride and dumped them in a ditch. The rest of the clan took up nesting elsewhere. They'd been dive-bombing the kids playing in the garden and crapping on my laundry on the line.