Comparison of acoustic particle acceleration detection capabilities in three shark species.

Behavioural studies have shown that sharks are capable of directional orientation to sound. However, only one previous experiment addresses the physiological mechanisms of directional hearing in sharks. Here, we used a directional shaker table in combination with the auditory evoked potential (AEP) technique to understand the broadscale directional hearing capabilities in the New Zealand carpet shark (Cephaloscyllium isabellum), rig shark (Mustelus lenticulatus) and school shark (Galeorhinus galeus).

Comparison of auditory evoked potential thresholds in three shark species.

Auditory sensitivity measurements have been published for only 12 of the more than 1150 extant species of elasmobranchs (sharks, skates and rays). Thus, there is a need to further understand sound perception in more species from different ecological niches. In this study, the auditory evoked potential (AEP) technique was used to compare hearing abilities of the bottom-dwelling New Zealand carpet shark (Cephaloscyllium isabellum) and two benthopelagic houndsharks (Triakidae), the rig (Mustelus lenticulatus) and the school shark (Galeorhinus galeus).

Operant conditioning as a tool to assess hearing abilities in sharks.

Sharks (elasmobranchs) are an ancient, diverse group of fishes, representing a basal stage in the evolution of vertebrate hearing. Yet, our understanding of behavioural measures of hearing abilities in sharks is limited. To address this, an operant conditioning paradigm was designed, and scalloped hammerhead Sphyrna lewini and rig (spotted estuary smooth hound) Mustelus lenticulatus were successfully trained to respond to pure-tone acoustic stimuli from an underwater speaker.