Hearing and Olfaction

Abstract Hearing and the sense of smell (olfaction) complement vision in gaining information about objects remote from the body. Hearing sensitivity in birds shows relatively little variation between species and sits well within the hearing capacities of young humans. Most birds have relatively poor ability to locate sounds in direction and distance. Only in owls does the accuracy of sound location match that of humans. A few highly specialized birds employ echolocation to orient themselves in the total darkness of caves. There is increasing evidence that olfaction is a key sense in birds guiding diverse behaviours across many species. Olfaction plays a key role in the location of profitable foraging locations at sea and on land, and in some species smell may be used to locate individual food items and nests. Olfaction may also play a role through semiochemicals in the recognition of species and individuals, and in mate choice.