Penguins absolutely have ears, and they hear quite well in both air and water. What they lack are the external ear flaps, or pinnae, that mammals use to funnel sound. Instead, a penguin’s ear openings sit on the sides of its head, hidden beneath a layer of specialized feathers. Beneath that modest exterior is a fully functional hearing system tuned for the dual demands of life on land and at sea, and the science of how it works has only recently come into focus.
What a Penguin’s Ear Looks Like
If you part the feathers on the side of a penguin’s head, just behind and slightly below the eye, you will find a small opening. This is the external ear canal, and it leads to a tympanic membrane (eardrum) and a middle ear much like those found in other birds. The feathers covering this opening are not just cosmetic. They are stiff, tightly packed, and angled in a way that protects the ear from wind, water, and debris while still allowing sound to pass through.
Penguins also have a ring of tissue and muscle surrounding the external ear opening. Research on penguin middle-ear anatomy has shown that these muscles can constrict the ear canal, effectively sealing the eardrum from the outside environment.1PubMed. Pressure equilibration in the penguin middle ear This likely helps manage pressure changes during deep dives, where a penguin may descend hundreds of meters in minutes. The ability to close off the ear canal on demand is an adaptation you do not see in land-dwelling birds, and it hints at how thoroughly penguins have been shaped by their aquatic lifestyle.
How Penguins Hear on Land
Penguin hearing in air has been measured in two different ways. One approach uses anatomical modeling, essentially building a computer simulation of the ear from CT scans and calculating how it responds to different frequencies. Another uses behavioral testing, training live penguins to respond to tones and noting the quietest sound they react to at each pitch. Both approaches agree on the general picture, though they produce somewhat different numbers at specific frequencies.
Anatomical modeling of the Little Penguin predicts that the best hearing sensitivity in air falls in a range from roughly 550 to 5,400 Hz, with peak sensitivity around 2 kHz.2Royal Society Open Science. Sound reception and hearing capabilities in the Little Penguin (Eudyptula minor): first predicted in-air and underwater audiograms Behavioral audiograms of African Penguins show a functional hearing range from about 250 Hz to 10 kHz, with the sharpest sensitivity at 2 to 4 kHz depending on the individual bird.3Scientific Reports. Biological relevance and methodological implications of unexpected hearing thresholds in a diving bird That best-sensitivity zone overlaps neatly with the frequency range of penguin calls, which makes sense: an ear tuned to hear your own species’ vocalizations is what natural selection would produce.
To put this in everyday terms, penguins hear well in the range that covers most human speech, birdsong, and the kinds of environmental sounds that matter on a rocky coastline. They are less sensitive at very low frequencies and lose hearing ability quickly above about 5 to 10 kHz. They would not hear a dog whistle, but they would hear you talking from a reasonable distance.
Hearing Underwater
Penguins spend a large fraction of their lives in the ocean, so the question of whether they can hear underwater is arguably more important than how they hear on land. Sound travels differently in water than in air. It moves faster, carries farther, and the physics of how it enters the ear change because the density of water is much closer to the density of body tissue.
Modeling of the Little Penguin’s ear predicts that underwater hearing sensitivity is best between roughly 200 and 6,000 Hz, with peak sensitivity near 1.5 kHz. Above 6,000 Hz, hearing drops off sharply.4Royal Society Open Science. Sound reception and hearing capabilities in the Little Penguin (Eudyptula minor): first predicted in-air and underwater audiograms – Section: 3.3 Predicted in-air and underwater audiograms The shape of the penguin’s predicted underwater audiogram closely matches that of the Great Cormorant, the only other diving bird for which underwater hearing data existed at the time of the study. The penguin’s sensitivity was slightly lower by about 2 decibels, with a slightly wider sensitive frequency range.4Royal Society Open Science. Sound reception and hearing capabilities in the Little Penguin (Eudyptula minor): first predicted in-air and underwater audiograms – Section: 3.3 Predicted in-air and underwater audiograms
It is worth noting how little we actually know about underwater hearing in diving birds. Almost all bird hearing research has been done in air, for obvious practical reasons. The Little Penguin study was the first to produce predicted audiograms for any penguin species both in air and underwater, and much of the underwater data for other species simply does not exist yet. What we can say is that penguins are not deaf underwater. Their ears work in both media, with the underwater sensitive range shifted slightly toward lower frequencies compared to their in-air performance.
Recognizing Family in a Crowd
Penguin colonies are staggeringly noisy places. Thousands of birds call simultaneously, and parents returning from foraging trips must find their specific chick in this acoustic chaos. The system penguins use to pull this off is one of the more remarkable examples of vocal recognition in the animal kingdom.
King Penguin chicks identify their parents primarily by the frequency modulation pattern within each syllable of the adult’s call, rather than by the overall pitch or volume. Experiments with modified playback signals showed that chicks still recognized a parent’s call even when the carrier frequency was shifted up or down by 75 to 100 Hz. But when the shape of the frequency modulation within a syllable was altered, recognition broke down. Chicks also needed only a small portion of the call to identify the parent: the first half of a syllable, lasting about a quarter of a second, and the first three harmonics were enough.5Animal Behaviour. Finding a parent in a king penguin colony: the acoustic system of individual recognition
The vocal mechanism behind this is itself unusual. Penguins, like many birds, have a syrinx with two independently controlled sound sources, one in each bronchus. Researchers have demonstrated that the “beat” pattern created by the interaction of these two fundamental frequencies carries identity information. This beat signal propagates well through the crowded, obstacle-rich environment of a colony, where bodies constantly block and reflect sound waves.6PubMed Central. Penguins use the two-voice system to recognize each other Further experimental work confirmed that the recognition process involves analysis of both the frequency modulation shape and the amplitude beat pattern generated by this two-voice system. When either cue was suppressed or reversed in playback experiments, the chicks failed to recognize the call.7PubMed. Intra-syllabic acoustic signatures used by the king penguin in parent-chick recognition: an experimental approach
This is an impressive feat of auditory processing. It suggests that penguin ears and brains are not just passively receiving sound but actively decomposing complex signals into components and comparing them against stored templates. The system works in conditions that would baffle most artificial speech recognition software: high ambient noise, sound reflections from thousands of nearby bodies, and calls coming from unpredictable directions.
Penguins Talk Underwater Too
For a long time, it was assumed that penguins used sound mainly on land, for colony life and breeding. Then, in 2020, researchers published the first evidence that penguins vocalize underwater while hunting. Using cameras and microphones attached to individual birds, they recorded over 200 underwater calls from King, Gentoo, and Macaroni Penguins during a combined total of nearly five hours of dive footage. The calls were extremely short, averaging about 0.06 seconds, with peak frequencies near 1,000 Hz for King Penguins and around 680 Hz for Macaroni Penguins. More than half of the recorded calls were directly associated with hunting behavior, typically preceded by a burst of acceleration or followed almost immediately by a prey-capture attempt.8PubMed Central. First evidence of underwater vocalisations in hunting penguins
What these calls are for is still debated. They could serve to startle or herd prey, communicate with nearby foraging companions, or serve some purpose researchers have not yet identified. Whatever the function, the discovery confirmed that penguin hearing is not just useful underwater but actually part of an active underwater acoustic life. Separately, experiments with Gentoo Penguins showed that penguins detect and react to underwater sounds played to them in controlled conditions, suggesting they may use sound cues for orientation or prey detection during dives.9PubMed Central. Gentoo penguins (Pygoscelis papua) react to underwater sounds
How Penguin Hearing Compares to Other Diving Birds
Penguins are not the only birds that dive for a living. Puffins, murres, and cormorants all pursue prey underwater, and their hearing has also been studied to varying degrees. The Little Penguin’s in-air audiogram has a similar shape to those of other diving birds, though its absolute sensitivity is somewhat lower than that of three alcid species (Atlantic Puffin, Common Murre, and Marbled Murrelet). The penguin’s audiogram fits more closely with non-alcid diving birds like the Great Cormorant.4Royal Society Open Science. Sound reception and hearing capabilities in the Little Penguin (Eudyptula minor): first predicted in-air and underwater audiograms – Section: 3.3 Predicted in-air and underwater audiograms
This pattern makes evolutionary sense. Alcids and penguins are not closely related; they evolved their diving lifestyles independently, on opposite sides of the planet. That their hearing systems ended up with a broadly similar frequency range is a case of convergent evolution: similar environmental pressures producing similar solutions. The ears of these birds are shaped by the same constraints. They need to hear colony calls on land, manage pressure changes at depth, and possibly use sound underwater for foraging or navigation.
An Evolutionary Clue from Fossil Penguins
Modern penguins differ from all other living birds in one specific aspect of their skull anatomy: the air-filled tympanic recesses on opposite sides of the head do not connect to each other. In most birds, these cavities communicate through an internal pathway, and this interaural connection is thought to help with sound localization. By comparing sound arriving at both ears through both external and internal routes, a bird can better pinpoint where a sound is coming from.
A study of the brain and sensory anatomy of Paraptenodytes antarcticus, a fossil penguin from the Miocene, found that this ancient species still had the interaural connection that modern penguins have lost.10Oxford Academic. Evolution of the brain and sensory organs in Sphenisciformes: new data from the stem penguin Paraptenodytes antarcticus This suggests that early penguins may still have used the interaural pathway for directional hearing, and that modern penguins lost it at some point during their evolution. Why they lost it is not settled. One possibility is that as penguins became more specialized for deep diving, the sealed ear canal and modified middle-ear structure that protect against pressure changes at depth made the internal connection unnecessary or structurally incompatible. Penguins may compensate for the loss by relying more heavily on other sound-localization cues, such as intensity differences between the two ears.
Noise Pollution and Why Penguin Hearing Is a Conservation Issue
The fact that penguins can hear underwater, and that they are sensitive to a range of frequencies produced by human activities, has turned penguin hearing into a conservation concern. African Penguins are known to be sensitive to sounds as low as 100 Hz, which overlaps heavily with the noise produced by seismic survey airguns and large vessels.
A tracking study of African Penguins found that birds foraging within about 100 km of active seismic survey operations changed their foraging direction, moving away from the seismic vessel and diverting from their traditional feeding grounds. This was the first documented case of a seabird showing avoidance behavior in response to anthropogenic underwater noise.11Scientific Reports. Avoidance of seismic survey activities by penguins When penguins are forced to forage in suboptimal areas, they may burn more energy for less food, and this matters enormously for a species already classified as endangered.
The longer-term picture may be even more troubling. Algoa Bay in South Africa, one of the last strongholds for African Penguins, experienced a significant increase in ambient underwater noise after ship-to-ship fuel transfer operations began in 2016. Noise levels, already high, increased by about 2 decibels, which sounds small but corresponds to a doubling of sound intensity. This increase coincided with a dramatic decline of roughly 85 percent in penguin numbers from the nearby colony at St Croix Island.12PubMed. Maritime traffic trends around the southern tip of Africa – Did marine noise pollution contribute to the local penguins’ collapse? The study’s authors noted that Algoa Bay has become one of the noisiest bays on Earth and urged management intervention to reduce the disturbance.
Causation is difficult to prove in wildlife population declines because so many factors act simultaneously: food availability, disease, predation, climate change. But the correlation between rising noise levels and collapsing penguin numbers at St Croix is striking, and the established sensitivity of penguins to low-frequency underwater sound makes noise pollution a plausible contributing factor. For a species that relies on underwater hearing for foraging and whose populations are already under severe pressure, even a partial impairment or behavioral disruption from chronic noise could tip the balance.
Why So Much About Penguin Hearing Is Still Unknown
Given how iconic penguins are, it is surprising how recently the basic facts of their hearing have been established. The first predicted audiograms for any penguin species, covering both in-air and underwater hearing, were published in 2024.13PubMed Central. Sound reception and hearing capabilities in the Little Penguin (Eudyptula minor): first predicted in-air and underwater audiograms Behavioral audiograms exist for only a handful of species. Underwater hearing has barely been studied in any diving bird, let alone across the 18 recognized penguin species. The discovery that penguins vocalize underwater while hunting was not published until 2020.
The reason for these gaps is largely practical. Penguins live in remote, harsh environments. Testing hearing in a live penguin requires either training the animal to respond to specific tones, a process that takes months, or measuring auditory brainstem responses with electrodes, which requires anesthesia and controlled conditions that are hard to create on a sub-Antarctic island. Underwater hearing is even harder to measure because you need to present calibrated sounds to a submerged animal while controlling for vibrations through the testing apparatus itself. Researchers have turned to anatomical modeling partly because of these logistical difficulties, using high-resolution scans of penguin heads to simulate how the ear structures respond to sound.
What this means for you, if you have been wondering whether penguins can hear: they certainly can, and they hear in more environments and with more sophistication than most people would guess. The ears are there, quietly doing their job beneath feathers that evolved to keep them hidden and protected. The science is catching up with the biology, but it has some ground to cover.