Early in the morning, when the sun has just begun to rise and you want to stay in bed, your cat yowling and your dog begging for breakfast are probably the loudest animals in the world (well, in your world). We dont dispute that.
However, scientists have measured how loud animal sounds are in the wild, and they are also very, very loud. Maybe even louder than your pets first thing in the morning, but probably not. But we were just saying that some animals can make noises that are so loud they could damage our ears. Not even your cat can do that, though she may try.
The pistol shrimp, also known as the snapping shrimp, is often claimed to be one of the loudest animals on Earth relative to its body size With its powerful snapping claw, the shrimp can create a loud popping sound that stuns prey and communicates with others But is it truly the loudest animal in the ocean? Let’s take a closer look.
Pistol shrimps belong to the Alpheidae family of snapping shrimps There are over 1,100 species in this family, with the genera Alpheus and Synalpheus containing the most species at 336 and 160 respectively [1].
These small shrimp growing to around 5 cm long are common inhabitants of tropical and temperate coastal waters. They can be found living in coral reefs, seagrass flats, and oyster reefs. Some species even inhabit freshwater caves!
The pistol shrimp gets its name from its disproportionately large snapping claw. This claw makes up over half the length of its body and is used for hunting, defense, and communication. By closing it rapidly, the shrimp creates a loud popping sound.
How Loud is the Pistol Shrimp’s Snap?
When the pistol shrimp closes its large claw, a high-pressure jet of water shoots out at speeds up to 62 mph [1]. This jet creates a cavitation bubble that quickly collapses, generating intense heat and pressure.
The snap can reach 218 decibels relative to a micropascal (dB re 1 μPa) [1]. For comparison, a jet engine is 140 dB and a .357 magnum pistol is 150 dB. The shrimp’s snap is so loud that it stuns and even kills small fish nearby [2].
Some sources list the pistol shrimp as the loudest animal on Earth relative to its body size [3]. At a distance of 4 cm, its snap registers at 80 kilopascals of pressure, comparable to the impact created by an object traveling at 60 mph [4].
Given its tiny size, producing such loud clicks is impressive. No wonder the shrimp’s snap has been described as being as loud as a pile driver! [5].
The Role of the Snapping Claw
The pistol shrimp’s powerful claw serves several purposes:
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Hunting – The shrimp lies in wait for prey, then springs out and stuns it with a loud snap. It pulls the immobilized prey back to its burrow to eat.
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Defense – The claw’s snap wards off predators and intruders. Some species live in colonies and use it to protect their shared burrows.
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Communication – Snaps communicate with other pistol shrimps. Colonies use them to maintain contact and coordinate activities.
Without its snapping claw, the pistol shrimp would struggle to survive. Interestingly, if the large claw is lost, the smaller one will regenerate into a new snapping claw. The shrimp is able to reverse the asymmetry, a feat unique in the animal kingdom [1].
Measuring the Shrimp’s Volume
Exactly how loud the pistol shrimp’s snap is compared to its body size has been debated. Early reports of it producing bubbles as hot as the sun were exaggerated [6]. Getting an accurate measurement is complicated by several factors:
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Small size – At just a few centimeters long, directly measuring the shrimp’s snap is difficult.
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Underwater habitat – Sound travels much farther in water than air, so comparisons are tricky.
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Snap variability – Larger claws produce louder snaps. Snaps also vary based on how rapidly the claw is closed.
While a few studies have tried quantifying the shrimp’s sound, there is still uncertainty around its loudness compared to body size. Some researchers conclude it does not produce the most intense sounds relative to size [7]. More study is needed for a definitive ranking.
Challenges of Measuring Ocean Animal Noises
Comparing noises produced by marine animals poses some unique challenges:
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Aquatic vs terrestrial – Measuring aquatic sounds using pressure rather than intensity makes comparisons to land animals difficult.
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Sound propagation – Sound travels much farther underwater before weakening. It is less directional than in air.
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Background noise – Oceans are naturally noisy places, complicating animal sound measurements.
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Accessibility – Recording sounds of animals like beaked whales deep diving is incredibly challenging.
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Behavioral context – Sounds vary based on factors like mood, group size, season, and orientation.
While the pistol shrimp’s snap is undoubtedly impressive, ranking ocean animal sounds remains tricky work. Many loud species likely remain undiscovered in the vast depths.
Other Loud Marine Animals
Though the pistol shrimp makes notable noise, it has some competitors for the title of loudest sea creature:
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Sperm whales – These massive whales emit echolocation clicks of up to 236 dB that stun giant squid [8].
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Beluga whales – Belugas produce clicks reaching 228 dB for long-distance communication and hunting [9].
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Snapping crocodile shrimp – This pistol shrimp relative creates snaps reaching 210 dB used in territorial displays [10].
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Mantis shrimps – Smashes from their club-like claws result in cavitation bubbles, high pressures, and even sonoluminescence [11].
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Toadfish – These vocal fish grunt at over 200 dB to attract mates and defend territories [12].
While the pistol shrimp makes an impressive amount of noise for a small creature, it has some tough aquatic competition from much larger animals. Still, its ability to stun prey with its claw earns it a high rank among loud ocean-dwellers.
The Takeaway
The pistol shrimp’s powerful snapping claw allows it to create underwater clicks reaching an estimated 218 decibels relative to 1 micropascal. This volume is extremely loud given the shrimp’s small size.
However, noise production by marine animals is complex to quantify. Factors like directionality and behavioral context come into play. Other sea creatures like whales likely produce louder absolute noise levels.
So while the pistol shrimp does not appear to be the definitive loudest animal in the ocean, its snapping claw grants it membership in the elite group of noisiest sea creatures. Its ability to stun prey and communicate with such loudness remains amazing given its diminutive stature.
Next time you are diving in tropical waters and hear a loud crack, take a closer look – you may have just witnessed the astonishing snap of a pistol shrimp!
References
[1] https://en.wikipedia.org/wiki/Alpheidae
[2] https://www.science.org/doi/10.1126/science.289.5487.2114
[3] https://www.bbc.com/news/science-environment-34278595
[4] https://www.science.org/doi/10.1126/science.289.5487.2114
[5] https://dosits.org/animals/sound-production/sources-of-sound/snapping-shrimp/
[7] https://asa.scitation.org/doi/10.1121/1.4789933
[8] https://www.cell.com/current-biology/fulltext/S0960-9822(15)00494-0
[9] https://jeb.biologists.org/content/222/Suppl_1/jeb212365
[10] https://www.int-res.com/abstracts/esr/v32/n1/p53-61/
How Loud Is Too Loud?
Human hearing has two components: frequency and intensity. As far as the frequency of sound waves goes, the human hearing range falls between 20 Hz to 20 kHz. Younger humans, like infants, can hear higher sounds.
As for intensity, humans can tolerate sounds up to about 120 decibels, which is the equivalent of a rock concert. As such, you do not want to expose yourself to sounds at that level regularly.
According to National Institute of Deafness and Other Communication Disorders, “Sounds at or below 70 A-weighted decibels (dBA), even after long exposure, are unlikely to cause hearing loss. However, long or repeated exposure to sounds at or above 85 dBA can cause hearing loss.”
A few of the animals in this article are behind some of the loudest recorded sounds, a list that also includes the Saturn V Rocket (204 decibels) and gunfire (about 140 decibels).
Greater Bulldog Bat
The greater bulldog bat, which is native to the Caribbean, uses echolocation to find food, like all bats. But instead of the more typical insects, these bats feed on fish. That means bulldog bats need to make a noise that can reach both the air they fly through and the water where their food swims.
Their echolocations can reach 140 decibels, which is equivalent to a jet engine.
But we humans get lucky again in sharing the world with these bats, since these exceptionally loud sounds are ultrasonic, meaning theyre outside the range of human hearing.
World’s Loudest Animal is Tiger Pistol Shrimp! But How Loud?
Which animal makes the loudest noise?
However, the animal at the top of our list – the tiger pistol shrimp – generates noise as a way of stunning its prey. 1. Tiger pistol shrimp Native to the Mediterranean, this shrimp (pictured above with a gobie fish) leads the list as the loudest living animal, topping over 200dB – louder than a gunshot.
Are water boatmen the loudest animals on Earth?
Relative to their size, water boatmen are the loudest animals on Earth. While many of the animals on this list call to attract a mate, water boatmen are the only ones that manufacture such sounds using their sex organ. By rubbing their penis against their abdomen, in an act called ‘stridulation’, a boatman can generate sound of up to 99dB.
Why do tiger pistol shrimp make noise?
“Altruism is very relevant to animal calling,” says Dr Michael Kokkina, a zoologist from the University of South Australia. “They want to spread the message far and wide.” However, the animal at the top of our list – the tiger pistol shrimp – generates noise as a way of stunning its prey. 1. Tiger pistol shrimp