It was back in the 1980s in Kenya’s Amboseli National Park, where researchers were left dumbstruck when a herd of elephants suddenly froze mid-stride. Without any audible warning, each lifted one of their feet, stood motionless for several seconds, and suddenly changed their direction of movement as one unified group. To the human observers, they were more than certain that there were no trumpets or no visible threat that they had witnessed. But beyond the realm of human hearing, an entire conversation had just unfolded.
Very often, elephants flap their ears like flags while rumbling, signalling to nearby herd mates that a long-distance broadcast is underway. [Photo © Wildlife SOS/ Mradul Pathak]
This mysterious moment led to one of the most remarkable discoveries in animal communication: elephant infrasound — a ‘hidden language’ that operates at frequencies far below what our ears can detect. It is a communication system so advanced and unique that scientists are only now beginning to decode its complexity.
The Invisible Symphony: What is Infrasound?
Infrasound refers to any sound below 20 Hertz (Hz), which is the lower threshold of human hearing. While we might occasionally feel these ultra-low frequencies as vibrations in our chest or bones, we cannot actually hear them. Elephants, however, have mastered this acoustic technique, producing powerful rumbles that typically range between 14 and 35 Hz. Think of infrasound as the bassline of nature: earthquakes rumble at similar pitches, and blue whales sing across oceans with it. For elephants, these vibrations travel up to 10 km (over 6 miles) through air and even farther (up to 32 km, almost 20 miles) via the ground, crossing hills and dodging obstacles.
Emma, Maya, and Phoolkali move as one during their walks at Elephant Conservation & Care Centre, connected by an invisible thread of infrasonic rumbles and seismic signals. What looks like peaceful grazing is actually a dialogue happening in frequencies below human hearing. [Photo © Wildlife SOS/ Atharva Pacharne]
How does it work so well? The answer lies in physics. Low-frequency sounds travel much farther than high-frequency ones. A human shout might carry only for a few hundred metres as compared to an elephant’s ability to create a powerful infrasonic rumble. In the open savannas of Africa or the dense rainforests of Asia, this long-distance communication system allows elephant families to coordinate movements, warn of dangers, and locate each other across vast territories.
How Elephants ‘Speak’
Elephants produce infrasound through a wonder of evolution: their massive larynx, the voice box located high in the throat, just behind the tongue. A research study conducted in 2012 tested an elephant larynx in a lab to arrive at their rumbling range. Rumbles are produced when air rushes over vocal folds in the larynx, amplified by the large resonant chambers of the throat and trunk, creating rumbles as low as 1 Hz in frequency or at 117 decibel of sound pressure. A human’s hearing frequency starts from 20 Hz, and reaches somewhere between 120 and 130 dB as the maximum volume of the sound the ears can take. Imagine turning on rock music in your audio system at home that pumps up the bass. That vibration in your ear is the language elephants ‘speak’ in.
Asian elephants distinctly make gentle chirps and squeaks that African elephants physically cannot. Though all elephant babies squeal, this vocalisation remains exclusive to Asian elephants in the case of adults. [Photo © Wildlife SOS/ Akash Dolas]
These infrasonic calls carry clear and purposeful meanings. Matriarchs often use specific rumbles to coordinate the herd’s movement and guide migrations. Mothers, separated from their calves, exchange soft ‘I’m here’ calls that help them locate each other across vast distances — much like a game of Marco Polo played silently over the landscape. During extreme weather conditions, like drought, elephants even hear distant thunderstorms via infrasound, leading them to race towards the rain water.
Interestingly, while studying elephant acoustics, researchers found that the pachyderms also have dialects! Kenyan herds use short, punchy rumbles; Namibians draw them out longer, passed down generationally, like an inheritance!
The Elephant’s Vocal Orchestra
While infrasonic rumbles steal the spotlight, elephants produce an impressive array of at least 14 distinct vocalisations. Each serves a specific purpose in their complex social world.
- Rumbles are the most frequently used calls. These are low, resonant sounds that form the backbone of elephant conversation. It majorly includes greeting rumbles when families reunite after separation, contact calls when individuals search for their group, and ‘let’s go’ rumbles, signalling it’s time to move. Scientists have identified rumbles that can be produced through both the mouth and the trunk.
Nasal rumbles, filtered via the elephant’s six-foot-long trunk, perform long-distance communication among elephants. [Photo © Wildlife SOS/ Atharva Pacharne]
- Trumpets are the iconic elephant sound most people recognise. These are sharp, high-frequency blasts (up to 470 Hz) that signal excitement, alarm, or distress. Young calves trumpet when they’re frightened or separated from their mothers, while adults use them during confrontations or moments of intense emotion.
- Roars are among the most powerful vocalisations, reaching 112 decibels for humans, which is not very far from the sound of a jet engine when it takes off. These sounds particularly communicate aggression or serious threat. Interestingly, the terrifying roar of the T-Rex in “Jurassic Park” was actually created using recordings of baby elephant roars!
- Chirps and Growls are gentle, modulated tones, particularly used frequently by Asian elephants. These intimate sounds are perfect for short-distance bonding, calming a restless calf, or maintaining contact within a close-knit group. Notably, during the times of distress, a chirp can quickly turn into a squeak to signal mild alarm, or maybe escalate into a full-throated roar when the situation worsens.
Perhaps most remarkably, recent research published in Nature Ecology & Evolution suggests that elephants may even have individual ‘names’. The study suggests that the elephants have specific calls, which they use to address particular family members. When recordings of these calls were played back, elephants responded only when they heard their own name being called!
Conversations Beneath Their Feet
Elephant communication extends beyond the air, as they fascinatingly use ground itself for signalling. When an elephant rumbles or deliberately stomps, apart from creating airborne sound, it generates seismic vibrations that ripple through the earth in the form of waves. These ground vibrations can travel even farther than airborne calls, potentially reaching other elephants as far as 32 km or 20 miles away, under favourable soil conditions.
Herds at our Elephant Conservation & Care Centre (ECCC) communicate by flicking or thumping their trunks against the ground — a gentle percussion that sends vibrations through the earth, signaling to others nearby that all is well. [Photo © Wildlife SOS/ Vineet Singh]
Elephants have evolved remarkable adaptations to exploit this communication channel. Their massive cushioned foot pads, containing specialised cartilaginous nodes, which act as both transmitters and receivers of seismic signals.
When elephants detect these underground messages, they engage in what researchers call “freezing behaviour”. They stand completely still, often with one foot raised, leaning forward to channel vibrations through their leg and shoulder bones directly to their middle ear. During the transmission, a unique muscle around the ear canal constricts, dampening airborne sounds and allowing the elephant to focus exclusively on seismic signals.
Using the dual communication system, through both air and ground, has profound implications for the survival of the elephants. Herds can share warnings about poachers or other dangers across large territories, where visual or even long-range vocal communication would be impossible.
Why Listening Matters?
Acoustic monitoring is not just academic: it’s a conservation tool. Passive listening can:
- Detect presence and movement of elephants across corridors.
- Provide early warning to communities of approaching herds.
- Help locate poaching events or gunshots (acoustic triangulation).
- Monitor changes in behaviour under stressors like habitat loss or infrastructure noise.
But there are major concerns as well. The constant rumble of highway traffic, industrial machinery, and urban expansion creates noise pollution that masks critical infrasonic messages. Studies show elephants living near busy roads must vocalise 30% louder to be heard, potentially disrupting communication vital for survival.
To us human beings, here’s how an elephant is communicating its mood, without any sound — look closely at an elephant’s eye, it widens when it is excited, scared, or stressed, and remains half-closed when it is relaxed. [Photo © Wildlife SOS/ Atharva Pacharne]
Conservationists have presented some innovative solutions, like, elephant underpasses lined with vibration-absorbing materials, protected ‘quiet zones’ during critical communication periods, and artificial signal boosters that amplify weakened calls. However, the challenge now is designing human development projects that coexist and align with these ancient communication pathways.
At Wildlife SOS, understanding elephant behaviour, which does include how they communicate, is fundamental to our mission. Whether working to reduce human-elephant conflict, or providing lifetime care in our rescue centres, we recognise that protecting these gentle giants means preserving not just their physical habitats but their ability to connect with each other as well. Join our mission and donate now to support the cause for elephant conservation and welfare, because the elephants have been talking all along. Perhaps it’s time we learned to listen!
Feature image: Mradul Pathak/ Wildlife SOS
