the feral chickens of Kauai

The story goes like this.

Several years ago, a big hurricane hit the island of Kauai. It knocked over chicken coops and tore down chickenwire, and the birds made a break for it. In the absence of any real predators (including people, since nobody there eats them), the feral chickens rule the island, growing fat and sassy on fallen fruit and earwigs. They've multiplied in numbers to the point where they easily outnumber the human population.

The roosters flout the conventional rules about when and where it's appropriate to crow, and they make all sorts of racket whenever the urge strikes.