Mobbing Calls of the Phainopepla

When mobbing potential predators, male Phainopeplas (Phainopepla nitens) utter smoothly upswept vocalizations, unlike the harsh, staccato mobbing calls of other birds and mammals. A Phainopepla repeats this call as it approaches the bottom of its diving arc over the predator. We suggest that these calls do not serve to attract additional mobbers to the scene. Rather, they appear to emphasize the diving attacks directed toward the predator.