Whales sense using vision, touch, sound, ultrasound, echolocation (emitting sound waves and sensing their reflections to determine the location of objects) and chemicals usually detected by smell-like senses and communicate with touch and sound. Even though they rely mainly on sound to communicate, most whales are able to see fairly well in both water and air. [Source: Eric J. Ellis and Allison Poor, Animal Diversity Web (ADW) /=]
Whales have poor senses of smell. There are some indications that some species have no sense of smell. Their eyes are very small and swivel inside its socket just like a human eye. The eyes are of little use because even in clear water they are protected from salt water by an oily substance. Whale have no external ears. Their tiny ear canals are only a few centimeters thick. Even so they have acute senses of hearing: the product of sensory organs in their head not their ears. Some species are believed to be able to detect sounds produced hundreds of kilometers away.
Toothed whales and dolphins use echolocation to locate objects. Baleen whales, unlike toothed whales, are not known to echolocate, but researchers have found fat pockets in the ears of baleen whales that are known to help toothed whales echolocate.
Whales can hear an extremely wide range of sounds, ranging from high sounds that are 13 times higher than the highest sounds that humans can hear to low sounds also beyond human hearing that can travel great distances in the ocean. Ear bones of whales and dolphins are the densest in the world. The are hollow and need to be incredibly strong to protect the delicate inner ear tissues from the pressure of deep dives. Some scientists believe sound travels from the jaw to the ear through a big lobe of fat. The outer ear is essentially useless.
Whale and dolphins are sometimes grouped into three categories depending on what range of sounds they hear best: 1) those that hear higher frequencies than the human range: 2) those that hear mid-range frequencies; 3) those that hear lower frequencies than the human range. Among those in the first group are river dolphins that navigate in cloudy water. The second group includes whales and dolphins that use echolocation to spot prey. Most of those in the third group are baleen whales that use low frequencies to send sound hundreds and thousands of miles across the ocean.
Websites and Resources: Britain-based Whale and Dolphin Conservation Society uk.whales.org ; International Whaling Commission (IWC) iwc.in ; Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Fishbase fishbase.se; Encyclopedia of Life eol.org; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; Monterey Bay Aquarium montereybayaquarium.org ; MarineBio marinebio.org/oceans/creatures.
Whales produce a variety of sounds. Depending on the species, they can produce clicks, whistles, bleeps, moans or sophisticated "songs." These sounds are made by the larynx.Baleen whales grunt, moan whistle, chirp and click to communicate, Humpback whales are famous for their songs and the wide range of otherworldly sounds they make. Male humpback whales "sing" for up to 40 minutes at a time, presumably to attract females. Low-pitched moans produced by some baleen whales are some of the loudest sounds produced by any animal. They carry underwater for hundreds of kilometers. [Source: Eric J. Ellis and Allison Poor, Animal Diversity Web (ADW) /=]
Toothed whales communicate with high-pitched whistles. These sounds are most likely produced by opening and closing nasal plugs. They also use higher-pitched clicks for echolocation (emitting sound waves and sensing their reflections to determine the location of objects), to navigate and to find food. They have a fatty organ called a melon on the forehead that focuses acoustic signals as they are emitted, and they receive sounds in the middle ear via the jaw. Toothed whales have a hearing range that greatly exceeds that of humans; they can perceive ultrasounds up to 120 kHz. Higher frequency sounds used for echolocation can define topography and identify the size, identity, distance and location of objects. Noise from shipping and submarines may interfere with this type of communication. /=\
In 1973, the U.S. Navy began its first tests to hide inter-ship communications by using prerecorded pilot whale noises as a mutually intelligible codebook. At that time, the Navy didn’t know how to project whale sounds at long distances. In 2018, Chinese researchers published studies indicating that today’s technology allows the long-distance broadcast of coded dolphin and whale songs.
Whales and Sound
Sound travels farther and moves four to five times faster under water than on land and through the air — roughly 1500 meters per second in seawater, compared to just 340 meters per second in air. Sound is created by waves of vibration that pass through a medium, such as water or air. Because the atoms in liquids are more tightly packed than in gases, sound travels much faster in the ocean. In the sea sound can also be funneled by submarine canyons. Loud sounds can be heard with little alteration hundreds of kilometers (miles) away. Yes, low tones can travel farthest, but their reach is affected by natural ocean sounds, such as waves, and human-caused noise pollution, such as shipping. Whales are believed to able to hear the sound of boat propellers and other whales even if they are very far away and may navigate by bouncing their sonar off underwater topographical features like seamounts and continental shelves.
Zoe Cormier of BBC Earth wrote: The evolutionary changes to the auditory equipment in dolphins and whales needed to be dramatic to accommodate the acoustic environment of the sea. Because water is denser than air sound waves enter the cetacean ear without a change in something called 'acoustic impedance': sound waves travel in a straight line through the head, rather than at an angle as in land-dwelling animals. The lack of a change in the speed or power of a sound wave as it reaches the skull of a whale generates what is called 'acoustic interference' between the two ears, which affects their ability to locate the source of a sound. [Source: Zoe Cormier, BBC Earth]
To counteract this, cetaceans have evolved to have a pocket of air inside each ear. The middle ear structures have moved from inside the skull to outside of it: the tympanic membrane (ear drum) and the ossicles (ear bones) are housed within a giant bulbous bony shell called the 'tympanic bulla'. There are other anatomical quirks, as referenced in a UCL blog, that make the cetacean auditory equipment so unique: the tympanic membrane is shaped like a cone and projects into the bulla, rather than stretched flat like a drum across the opening to the ear canal as in our own species. “In a baleen whale, the membrane is like a big flag flapping around on a flag pole, while in dolphins it’s more rigid, like a tuning fork,” says Professor Christopher Clark, a cetacean specialist in the Department of Neurobiology and Behavior at Cornell University.
According to National Geographic: Yaps and fin slaps, growls and groans — whales use a wide range of sounds to communicate. But only five whale species — blue, bowhead, fin, humpback, and minke — are known to sing, with humpbacks the unrivaled musical masters of the sea. Smaller whales typically produce higher frequency signals, while massive blue and fin whales can sing at pitches too low for humans to hear. [Source: Alberto Lucas López and Oscar A. Santamariña, National Geographic April 15, 2021]
Zoe Cormier wrote for BBC Earth. Humpback whales are the world record holders for the number of vinyl records pressed of their music: 10 million copies of 'Songs of the Humpback Whale' were inserted into National Geographic magazine in 1979 – in 10 languages. Humpback whales have what many zoologists to be a form of culture: whales in different regions will have different songs from year to year, all the males singing the same song, what musicologist David Rothenberg, author of 'Thousand Mile Song', describes as an “anthem”. Remarkably, humpbacks can collective change the song as a group – within a week all the males will synchronise with each other to a new pattern of shrieks, growls, moans and rumbles. [Source: Zoe Cormier, BBC Earth]
Though ancient sailors were known to hear the calls of whales through the hulls of ships, they likely didn’t know what they were hearing (and it is thought attributed the sounds to mermaids). Scientists only discovered whale song in the 1950s when American scientists stationed in Bermuda heard the calls while listening out for Russian submarines. For 15 years, the navy kept the knowledge of whale songs a secret, until in 1967 engineer Frank Watlington gave recordings of the songs to biologist Roger Payne, who was a specialist in bat and owl vocalisations. Watlington had discovered that the whale songs consisted of a series of phrases that would be repeated perfectly, over and over.
Payne went on to study humpback whale songs, and discovered that all the males in a population will sing a new song every year. Together Payne and Watlington released the songs as the album Songs of the Humpback Whale in 1970, and arguably kick-started the environmental movement. When millions of people became aware that these incredible songs came from animals that humans had been slaughtering en mass for hundreds of years, huge protests led to the 1972 United Nations Conference on the Human Environment 10-year global moratorium on commercial whaling – which at the time was close to driving whales completely into extinction. Inadvertently, military research led to biological enlightenment and conservation movements.
Baleen Whales — the Kings of Long, Loud, Low Frequency Sound
Most baleen whales communicate over long distances with low frequency sounds. Some large whales produce sounds that reach 180 decibels, strong enough to bruise the lungs of humans swimming nearby. According to the BBC: Baleen whales rule supreme over the lower registers — the bass notes of the zoological musical scale. They sing to each other with rumbling, low moans and growls that often are too low for humans to hear. Blue whales for example can make calls just 14Hz in frequency, invisible to our ears. Because low frequency sounds travel further with less scattering, distortion and transmission loss, baleen whales can communicate to each other over enormous distances – thousands of kilometers.
They accomplish this through an ingenious tactic: making their calls within something called the 'deep sound channel', also known as the SOFAR channel (for Sound Fixing and Ranging channel). Due to the physical properties of the ocean, sound waves diminish in volume rapidly close to the surface, but at varying depths below the surface, depending on latitude, sound waves suffer little transmission loss and increase in the speed at which they travel. Whale songs can travel for thousands of kilometers through this horizontal band of water, which is often termed an 'acoustic guide'. Cold war scientists discovered the channel in the 1940s and figured out how to utilise it in submarine warfare, but strategically using the channel to listen for Soviets subs thousands of kilometers away.
Long before the navy figured out how to harness the acoustic properties of the ocean’s depths to send signals as far as possible, whales developed behavioural strategies to communicate with each other over enormous distances: the call of a fin whale for example may travel 250km at the surface, but more than 6,000km in the deep sound channel. “If a whale is near the surface, their calls will bounce off the surface of the sea and the ocean shelf, and quickly dissipate,” explains Prof Clark. “But once that animal plummets into the abyss, due to the physical refraction of the ocean, the energy of their calls get trapped in this layer and can travel farther and faster. That’s how I can hear blue whales singing off the coast of Ireland with a hydrophone placed in the water in Virginia.”
Baleen whales use this channel not just for communicating with each other, but also for navigating, by listening to the echoes of their calls bouncing off distant ocean shelves and coastlines, creating mental maps of the ocean. “I have tracked blue whales slaloming from sea mounts to islands to shelves – they don’t move in random directions, to go straight for features that are illuminated by their voices, sending out calls with wavelengths as long as a football pitch. It’s not echolocation, it’s more like ‘echomapping’ or ‘echoraging’. To study these animals I had to completely change my sense of time and space, because sound waves travel 25km in just one minute – so if a sound has to travel 250 miles to hit a coastal shelf, it will take ten minutes to hit the shelf and then ten minutes to come back. Humans just aren’t used to waiting twenty minutes to hear an echo. But these animals can do this, creating acoustic maps of their environments.”
Not only can baleen whales emit calls that travel farther than any other voice in the animal kingdom, these giants of the deep also create the loudest vocalisations of any creature on earth: the call of a blue whale can reach 180 decibels – as loud as a jet plane, a world record. Baleen whales also create the longest-lasting calls in the animal kingdom, with their famous songs (believed to be for reproduction, though that remains unproven). The world record holder for this is the humpback whale: males will sing for several hours at a time (repeating one song about 10 minutes in length over and over). The patterns of shrieks, growls and moans they sing repeats - just as human musical melodies do - and while a single session usually lasts up to 30 minutes, they have been known to last up to 23 hours.
Different Voices of Toothed Whales
Toothed whales and dolphin speak in different voices, including deep, gravelly one called. "vocal fry" to help find their prey, according to a paper published in the journal Science in March 2023. The study also found that whales, like people, have three vocal registers: a normal voice, a falsetto along with creaky fry. "The similarities we find are really striking," said Coen Elemans, a voice scientist at the University of Southern Denmark who led the study. "This is the first evidence of broad register use in any animal, besides humans." [Source: Dino Grandoni, Washington Post, March 3, 2023]
The Washington Post reported: Elemans and his colleagues found that toothed whales use the normal and falsetto registers to communicate with each other. They reserve the vocal fry register for navigation...especially in very deep water where they hunt in nearly complete darkness. The animals use sound to find their way underwater, sending out powerful pulses and listening to the echo to spot their meal. Toothed whales rely on vocal fry to make their echolocation clicks, according to the study. Under the sea, air is precious — and whales likely evolved to use the lower register for echolocation since it uses air the most efficiently.
Vocal fry, according to Elemans, "has definitely brought toothed whales very far." His team's series of experiments showed that whales produce their wide repertoire of sounds with the same organ — the phonic lips in their nose, which vibrate much like a larynx does in humans. To reach that conclusion, his team filmed tissue motion on trained bottlenose dolphins and harbor porpoises with a high-speed camera, and also taped wild whales with a small sound-recording tags. "They show, to some extent, that the physical mechanism is the same as the one we use," said Andrea Ravignani, a comparative bioacoustician at Aarhus University in Denmark and the Max Planck Institute for Psycholinguistics in the Netherlands. He wrote an opinion article on whale vocalization in the same issue of Science. He added, "The finding is quite unexpected and mind-blowing."
The 52-hertz whale, also referred to as 52 Blue, is an individual whale of unidentified species that calls at the unusual frequency of 52 hertz. This pitch is at a higher frequency than that of the other whale species with migration patterns most closely resembling it — the blue whale (10 to 39 Hz) and the fin whale (20 Hz). Its call has been detected regularly in many locations since the late 1980s, and appears to be the only individual emitting a whale call at this frequency. However, the whale itself has never been sighted; it has only been heard via hydrophones. It has been described as the "world's loneliest whale", though potential recordings of a second 52-hertz whale, heard elsewhere at the same time, have been sporadically found since 2010. [Source: Wikipedia]
The migration track of the 52-hertz whale is unrelated to the presence or movement of other whale species. Its movements have been somewhat similar to that of blue whales, but its timing has been more like that of fin whales. It is detected in the Pacific Ocean every year beginning in August–December, and moves out of range of the hydrophones in January–February. It travels as far north as the Aleutian and Kodiak Islands, and as far south as the California coast, swimming between 30 and 70 kilometers each day. Its recorded distance traveled per season has ranged from a low of 708 kilometers to a high of 11,062 kilometers in 2002–03.
The 52-hertz whale was discovered by a team from the Woods Hole Oceanographic Institution. Its call was first detected in 1989, then again in 1990 and 1991. In 1992, following the end of the Cold War, the U.S. Navy partially declassified the recordings and technical specifications of its SOSUS anti-submarine hydrophone arrays, and made SOSUS available for oceanographic research. As of 2014, the whale had been detected every year since.
South Korean group BTS's 2015 album The Most Beautiful Moment in Life, Pt. 2 includes the track "Whalien 52", which explicitly uses the 52-hertz whale as a metaphor for the alienation from others often felt by adolescents. The title of the Taiwanese movie 52Hz, I Love You (2017) is inspired by the whale, using it as a metaphor for the loneliness experienced when looking for love.
Image Source: Wikimedia Commons, NOAA, graphs of whale sounds from Wildlife Conservation Society
Text Sources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.
Last Updated June 2023