A bird feeder comprising a hopper suspended above ground by a hanger for holding granular bird seed, and a collapsible feed trough through which the seed flows. The trough consists of a series of pivotally interconnected ramps that unfold during deployment into a zigzag configuration. An uppermost ramp is fixedly secured to the hopper, and successive lower ramps are pivoted to each other in an angular "zigzag" arrangement. Each ramp is inclined relative to the horizontal approximately thirty degrees. Each ramp has a discharge hole at its lower end that is large enough for seed to fall through to a lower ramp. In response to vibration, seeds exit the hopper and travel through the trough. When the feeder is to be stored or shipped, the trough is collapsed by folding the ramps into a nested, retracted position.