Several animals exploit saguaro holes, but only woodpeckers make them. There are two main hole-makers in this desert - the Gila woodpecker and the Gilded flicker.
Both scoop out holes in the saguaro, but the Flicker does serious harm because it digs too deep. This damages the saguaro's internal woody ribs, and damage to the ribs endangers the plant's growing tip. Look out for these 'ribs' in dead saguaros.
