Alarm calls of Honeyeaters with reference to locating sources of sound

Abstract

The alarm calls that are given in response to a flying hawk by the New Holland Honeyeater Phylidonyris novaehollandiae, the White-plumed Honeyeater Lichenostomus penicillatus and the White-naped Honeyeater Melithreptus lunatus are described. Animals locate sources of sound by comparing differences in intensity, phase and timing cues of the incident sound at each ear. These processes are explained and previous explanation is criticized. Some animals create more directional cues from incident sound with pinna. The structure of the alarm calls of honeyeaters makes them easy to locate and some honeyeaters possess specialized ear-feathers that may function as pinna. The function of the alarm calls is discussed with reference to survival value.