Animals that echolocate include bats, toothed whales such as dolphins and porpoises, and a small number of other mammals, including certain shrews and tenrecs. They make sounds and use returning echoes to detect objects, navigate, or find prey; most animals do not echolocate, and the ability varies widely among those that do.
What echolocation means
Echolocation is a way of gathering information by producing sound and interpreting the echoes that return after sound waves meet an object. The sound may be a brief click, a pulse, or a call. Its echo can reveal that something is nearby and provide clues about its distance, direction, size, shape, or movement.
The word is often associated with darkness, but echolocation is not simply “seeing with sound.” It is a distinct sensory process that works alongside other senses. A bat may use vision as well as echolocation, and a dolphin can rely on hearing, touch, and other sensory information. The relative importance of each sense depends on the animal and the situation.
There is no single list that captures every borderline case. Some animals clearly produce sounds and use their echoes to locate prey or avoid obstacles. In other species, researchers are still investigating whether a sound is used in this way, or whether it serves another purpose, such as communication.
Bats: the best-known echolocators
Many bats echolocate, particularly species that hunt insects in the air or move through cluttered habitats at night. They produce high-frequency calls, commonly through the mouth or nose, and listen for echoes with their sensitive ears. The returning sound helps them track moving insects and avoid branches or other obstacles.
A bat’s calls are not always identical. When it is searching across open space, it may produce calls suited to detecting targets at a distance. As it closes in on an insect, it can call more rapidly, creating a detailed stream of echoes that helps it refine the target’s position. This rapid sequence is often called a “feeding buzz.”
Not all bats echolocate in the same way. Some fruit-eating bats rely heavily on sight and smell when finding food, while certain members of those groups also use audible clicks or other forms of echolocation in particular circumstances. “Bats echolocate” is a useful generalization, not a claim that every bat species uses the same technique or depends on it equally.
Toothed whales: echolocation underwater
Toothed whales, a group that includes dolphins, porpoises, sperm whales, and beaked whales, use echolocation. They produce clicks and receive echoes through a specialized hearing system. In many dolphins, sound is focused into a forward-directed beam, with structures in the forehead helping shape the outgoing signal. Echoes are received through tissues in the lower jaw and transmitted toward the inner ear.
These animals use echolocation to investigate their surroundings and locate prey in water, where visibility may be poor. A dolphin can use returning echoes to distinguish a target from nearby objects. Different species produce different sounds and have different abilities, so it is misleading to picture every toothed whale as using one identical sonar system.
Baleen whales, such as blue whales and humpback whales, are not generally regarded as echolocators. They produce sounds, but making sound alone does not establish echolocation: the key is using returning echoes as a meaningful source of information. This distinction also applies to many other animals that call, sing, or click.
Other mammals that use echoes
Some shrews and tenrecs produce sounds and appear to use echoes to help orient themselves, especially in dark or complex surroundings. Their echolocation is generally less specialized than the familiar systems of bats and toothed whales. It may help with nearby navigation rather than provide the detailed prey tracking associated with many hunting bats.
The exact abilities differ by species, and scientists continue to study how these animals use sound. It is safer to say that echolocation or echo-based orientation has been documented in certain small mammals than to claim that all shrews or all tenrecs echolocate. A species’ habitat, behavior, and sound production all matter when assessing the evidence.
Humans can also learn to make clicks and interpret their echoes, a skill sometimes called human echolocation. It is a learned ability, not a biological sonar system comparable to that of a bat or dolphin. Some blind people use tongue clicks or other sounds to gather information about nearby surroundings, but this does not mean that humans naturally echolocate in the same way other species do.
How echolocation works
The basic process has three parts: producing a sound, receiving its echo, and interpreting the returning information. Sound travels outward, reflects from surfaces, and returns to the animal. The time and character of the echo can offer useful clues. A nearer object generally returns an echo sooner than a farther one, while changes in the echo can signal movement or differences in the reflecting surface.
Animals must separate their own outgoing sounds from the echoes they need to hear. They also have to make sense of echoes that overlap or arrive from several objects. Specialized hearing, timing, and sound production help echolocating species solve these problems. The details are different in air and water: sound behaves differently in each medium, and bats and whales have evolved distinct ways to produce and receive it.
- Call structure: The pitch, length, and pattern of a sound affect the information its echo can carry.
- Timing: The interval between a call and its return helps indicate how far away a reflector is.
- Direction: Differences in sound reaching the two ears, along with other hearing cues, help locate a target.
- Changes over time: A sequence of echoes can reveal whether an object is moving and how its position is changing.
What echolocation is used for
Finding food is a major use, but echolocation has several roles. Insect-eating bats can detect and pursue prey in flight. Dolphins can locate prey and inspect objects in water. Small mammals that use echo-based orientation may benefit from information about obstacles or nearby spaces, even when their system is not finely tuned for hunting.
Echolocation can be especially useful when vision is limited, but darkness is not a requirement. A bat may echolocate at night because it is active then, while a toothed whale may use clicks in murky water. In both cases, the sound supplies information that sight alone may not provide.
It is also useful to distinguish echolocation from communication. A sound can serve one purpose, the other, or possibly more than one depending on its context. A whale’s call or a bat’s social vocalization should not automatically be described as echolocation just because it travels through the environment and may produce an echo.
How echolocators compare with other animals
Many animals hear sounds without producing them to locate objects. Owls, for example, can use sound to find prey, but they are not usually described as echolocators because they mainly listen to sounds made by other things. Likewise, animals that make loud calls are not echolocating unless they use returning echoes to gather information about their surroundings.
Some birds, including oilbirds and swiftlets, use clicks for orientation in dark spaces. Their sound-based navigation is often compared with echolocation, although the systems and degree of specialization differ from those of bats and toothed whales. Such examples show why the question is not simply whether an animal makes clicks; researchers ask whether it produces sound and uses the echo to guide behavior.
Ordinary hearing and echolocation can work together. A bat may hear an insect’s own sounds as well as the echoes of its calls. A dolphin can hear sounds from other animals while producing clicks of its own. Echolocation is therefore best understood as a specialized way to add information, not as a replacement for every other sense.
Common misconceptions
- “All bats are blind.” Bats are not blind; many can see, and some rely on vision along with echolocation.
- “Any animal that makes a sound echolocates.” Sound production is not enough. The animal must use returning echoes to detect or interpret its surroundings.
- “Only animals in total darkness use echolocation.” The ability can be helpful when visibility is poor, but it is not limited to complete darkness.
- “Baleen whales use the same sonar as dolphins.” Baleen whales make sounds, but they are not generally classified as echolocators in the way toothed whales are.
Frequently Asked Questions
Which animals use echolocation?
Bats and toothed whales, including dolphins and porpoises, are the clearest familiar examples. Certain shrews and tenrecs also use echolocation or echo-based orientation. A few birds use clicks to navigate in dark spaces, though their systems are not identical to mammalian sonar.
Do all bats echolocate?
No. Echolocation is widespread among bats, but species vary in how they produce sounds and how much they rely on them. Some fruit-eating bats depend more on vision and smell, and not every bat uses the same echolocation strategy.
Do dolphins echolocate?
Yes. Dolphins are toothed whales and use clicks and returning echoes to locate and investigate objects, including prey. Their sound production and hearing systems are adapted for underwater echolocation.
Can humans echolocate?
Humans can learn to use clicks and interpret echoes for nearby spatial information. This learned skill is not the same as the highly specialized biological echolocation used by bats and toothed whales.
Do whales echolocate?
Toothed whales, including dolphins, porpoises, and sperm whales, do. Baleen whales are not generally considered echolocators. “Whale” covers diverse groups, so the answer depends on which kind of whale is meant.
The short answer
The strongest examples of echolocating animals are bats and toothed whales. Some small mammals and certain birds also use echoes for orientation, while sound-making by itself does not count. The defining feature is that an animal produces sound and uses the returning echo as information about the world around it.