The Role of Olfaction in Shark Predation

Abstract

It is recognized that most if not all species of sharks possess a keen sense of smell which is used in detecting dead and wounded prey or other edible material during their well-known scavenging operations. The early experiments of Parker (1910), Sheldon (1911), and Parker and Sheldon (1913) established the role of the paired nasal organs as olfactory receptors. Parker (1914) demonstrated directional response in the smooth dogfish (Mustelus canis) and provided a plausible explanation of how this was accomplished; he postulated that the two separated nostrils have the ability to detect small differences in the concentration of odorous materials enabling the shark to orient in the direction of equal stimulation and to head "upstream" to the source. This tracking ability is well recognized by skin divers and fishermen who have involuntarily attracted sharks by retaining speared fish or by discarding trash fish and offal from their boats.