Listen Up

You might imagine that the underwater world is a serene, peaceful place, but for the creatures that have evolved to live underwater, that could not be further from the truth. Sound travels further in water than in air and so many animals - including thousands of fishes - make sounds to communicate with each other. So in reality, the marine realm hosts a busy and intense soundscape. Sounds can be used as landmarks or cues; and vocalising or producing sounds somehow can be used to threaten or seduce, to organise, or to make friends. But how do sharks use their hearing? Are sounds important in their daily lives? And can sharks make their own sounds?

Estuary smoothhounds are the first sharks that scientists have recorded making sounds (Image Credit: Poetra RH / Adobe Stock)

Bring the Noise

Believe it or not, sharks have very good hearing and they rely on sound as their longest- range sense. They can hear things before they smell them and so their hearing is critical for sharks to track down prey, find mates and navigate (Abel & Grubbs, 2020; Ebert et al, 2021).

Sharks can hear a struggling fish from up to 3km away

You would be forgiven for not realising how important their hearing is because sharks’ ears are basically invisible to the naked eye. In every species, there are no external structures and the ears are just two tiny pore-like paired openings that sit on the very top of their heads. Yet whilst these might look quite different on the outside, the internal structure of sharks’ ears are very similar to ours (Abel & Grubbs, 2020). 

Sharks ears are most sensitive to low frequency sounds that travel especially far in water. For instance, bull sharks’ (Carcharhius leucas) hearing peaks around 200 - 400 Hz, but they are capable of hearing any sounds between 40 - 1,500 Hz. Despite humans having a much wider hearing range - between 20 - 20,000 Hz - there are several species of sharks that are able to hear frequencies lower than human ears pick up. For example, lemon sharks (Negaprion brevirostris) and horn sharks (Heterodontus francisci) are able to detect 10 Hz sounds (Myrberg, 1987;  Bres, 1993; Meredith et al, 2022).

I Hear You!

Generally, the range of a shark’s hearing ability depends on their particular habitat, feeding ecology and mode of locomotion. For instance, free-swimming sharks have the greatest sensitivity to very low frequency sounds. In the open ocean, up in the water column, away from any landmarks like rocks or corals on the substrate, being able to detect sounds that proliferate over very long distances is vital for these sharks. Comparatively, sharks that live around bustling coral reefs and/or those that have a fish based diet have the largest inner ears, as their hearing is vital for finding a good spot for a fish dinner (Myrberg, 1987; Bres, 1993; Chapuis et al, 2019; Meredith et al, 2022; White, 2024).

Sharks that live around coral reefs have very large, well developed inner ears, so it's thought their hearing is important for them in their daily activities (Image credit: frantisekhojdysz / Shutterstock)

Sharks also rely on their hearing to avoid bigger, badder predators. Sharks are most curious towards low frequency, pulsed sounds and playing these through a hydrophone into the water can draw sharks from miles around. On the other hand, there are many noises that repel sharks. Single loud tones startle young young lemon sharks (Negaprion brevirostris) and silky sharks (Carcharhinus falciformis), and sudden increases in volume will cause even the foreboding oceanic whitetip (Carcharhinus longimanus) to retreat. Like any other animal that jumps in response to loud noises, this is sharks responding to a potential threat in their environment in order to protect themselves from harm. Unsurprisingly orca vocalisations have been found to be especially effective at repelling sharks, including all the aforementioned species and various reef sharks (Carcharhinus species), even great whites (Carcharodon carcharias) will flee from their calls (Myrberg, 1987; Bres, 1993; Chapuis et al, 2019).

The ability to recognise and remember a sound, and what it means is vital for survival and scientists have had  a lot of fun proving that sharks are capable of such advanced auditory discrimination. Port Jackson sharks (Heterodontus portusjacksoni) can be trained to associate music with food rewards and to swim to a specific area of the tank to be fed whenever they hear music, suggesting they do rely on auditory cues (Vila Pouca & Brown, 2018). To learn more, head over to Move To The Music.

Port Jackson sharks can be trained to recognise and respond to music (Image Credit: Mark Norman - Museum Victoria / WikimediaCommons)

Jump Around

Sharks do not have vocal cords, so they cannot sing or talk,  but that does not mean they do not use sounds to communicate. Sharks regularly create noises by moving and so it is suspected that they may use their bodies to send messages to other sharks (White, 2024).

White sharks may make sounds with their tails to communicate (Image Credit: / Alessandro de Maddalena / Shutterstock)

Several species of sharks are known to jump out of the water and whilst there are several possible explanations for this (see Jumping the Shark), one idea is that they could be using the sound created by their landing as a way to communicate with other sharks. For example, as males and females perform differently, scientists suspect that jumping and spinning might be a way for basking sharks (Cetorhinus maximus) to attract a mate (White, 2024). For more information, head over to Spinning Around.

Great whites (Carcharodon carcharias) are thought to use the sounds created by their tails to fight over food resources. Bringing their tails out of the water and crashing them down onto the surface to create a loud sound and large splash is the way that these mighty sharks fight like gentlemen. It's thought that whoever makes the loudest noise and/or directs the most impressive wave at his opponent, wins the bout (Klimley, 2023). Good form!

Scientists wonder if sharks may jump in order to create a sound upon landing, to communicate with other sharks (Image Credit: Steve Momot / WikimediaCommons)

Make It Snappy!

Cowtail stingrays snap their teeth at divers that come too close (Image Credit: dennis and aimee jonez / WikimediaCommons)

Several studies on sharks’ close relatives - the batoids - have confirmed that there are a few species that create noises when they are disturbed. Wild mangrove whiprays (Urogymnus granulatus) and cowtail stingrays (Pastinachus ater) in Australia and Indonesia, and blonde rays (Raja brachyura), rough skates (Raja radula) and marbled electric rays (Torpedo marmorata) in the Mediterranean, make clicking sounds with their teeth when divers approach too closely. Making sound like this is known as "stridulation" and it can be used to communicate distress and/or to ward off threats (Nieder et al, 2025). 

A recent study performed with spotted estuary smoothhounds (Mustelus lenticulatus) in the lab, suggests some sharks may make similar noises when they are distressed. These smoothhounds produced nine or ten single- or double-pulsed clicking sounds by forcefully snapping their flattened teeth together whilst being touched by researchers, but were quiet when they were left to their own devices (Nieder et al, 2025). 

Scientists think estuary smoothhounds clack their teeth together to create a clicking noise when they are distressed (Nieder et al, 2025)

It is not clear whether these sharks are actually able to hear their own clicks, so scientists don't think they make these noises to communicate with other members of their species. It is more likely that sharks make this noise because they are distressed or as a way to say “back off” to a large predator (Nieder et al, 2025).

This is the first example we have of sharks actively using a body part to produce a sound, but as many other sharks in this family have similar dentition, it is very possible that many other species make similar sounds as well. So this finding raises many questions about how many sharks might be able to make noises and how else sharks use sound to communicate.

Several species of batoids, included marbled torpedo rays, clack their teeth to make noises (Image Credit: Philippe Guillaume / WikimediaCommons)

References

Abel DA & Grubbs RD (2020). Shark Biology and Conservation: Essentials for Educators, Students and, Enthusiasts. Johns Hopkins University Press: USA. 

Bres M (1993). The behaviour of sharks. Reviews in Fish Biology and Fisheries, 3, 133-159. Access online.

Chapuis L, Collin SP, Yopak KE, McCauley RD, Kempster RM, Ryan LA, Schmidt C, Kerr CC, Gennari E, Egeberg CA & Hart, N. S. (2019). The effect of underwater sounds on shark behaviour. Scientific reports, 9, 6924. Access online.

Klimley AP (2023). A historical approach to describing the complex behaviour of a large species of predatory shark—case study 2: The white shark, Carcharodon carcharias. Behaviour, 160:11-14, 1103-1136. Access online.

Meredith TL, Kajiura SM, Newton KC, Tricas TC & Bedore CN (2022). Advances in the sensory biology of elasmobranchs. In: Carrier JC, Simpfendorfer CA, Heithaus MR & Yopak KE (Eds.). Biology of Sharks and their Relatives, third Edition. CRC Press: USA. pp. 143-176.  

Myrberg Jr AA (1987). Understanding shark behavior. In: Cook S (Ed.), Sharks: an inquiry into biology, behavior, & fisheries, and use. Proceedings of the Conferences Portland, Oregon, pp. 41-83. Access online.

Nieder C, Parmentier E, Jeffs AG, & Radford C (2025). Evidence of active sound production by a shark. Royal Society Open Science, 12:3, 242212. Access online.

Vila Pouca C & Brown C (2018). Food approach conditioning and discrimination learning using sound cues in benthic sharks. Animal Cognition, 21, 481–492. Access online. 

White CE (2024). The Acoustic Landscape of Shark Habitat. Doctoral dissertation, University of Exeter, United Kingdom. Access online.

By Sophie A. Maycock for SharkSpeak