People usually think of big animals when they are asked to name loud animals. The roar of a lion, the trumpet of an elephant, and the song of the mighty blue whale But in many underwater environments, the smallest animals are among the loudest. Snapping shrimp, also called pistol shrimp, live in a range of shallow water ocean habitats, such as coral reefs, temperate kelp forests, sponge-dominated areas, and rocky bottoms. Their bodies are only a few centimeters long, but their snapping claw can get up to twice as big. When closed, the clawâs hinge produces a bubble which bursts and makes a loud snap sound. At 183-210 decibels, this makes them some of the loudest sound producers in the ocean.
No one really knows why they make this sound, even though they are loud. This is because they are small and like to hide in cracks. Most snaps are recorded when shrimp are fighting over territory, digging burrows, or reacting to changes in their environment. Scientists believe that shrimp also use the sound to scare off prey and keep predators away.
Snapping shrimp are common in places where you can snorkel or dive and hear their crackling sound. This is often the most recognizable and memorable sound. For people who haven’t heard this before, it sounds like when you pour milk over Rice Krispie cereal and it pops.
Spectrograms are ways of looking at sound. This 10-second recording from Gray’s Reef National Marine Sanctuary shows what we hear when we dive close to snapping shrimp: the loudest sounds are made by their collective snapping, which is shown by lighter blue to yellow colors across most of the tones or frequencies we recorded (vertical axis). and sound: NOAA.
People have started to notice changes in the sounds they hear underwater after an oil spill, hurricane, coral disease, or bleaching. This is because many avid divers are very sensitive to the sounds they hear. We know from personal experience that these places don’t snap as much as they used to. Now we’re looking at underwater recordings made before, during, and after efforts to fix up damaged habitats. These studies show that the amount of snapping can help us figure out how well our efforts to restore ecosystems are working or even help us build them back up. Because their sound helps marine larvae and fish find good places to live, animal species that return to the soundscape early may let other living things know that the place is good for them.
Sounds pretty snappy! But there are big caveats. Before we can figure out if changes in snapping are linked to how healthy a habitat is, we need to know why snapping changes in the first place.
Weâve all been taking our temperatures a lot this year. So we know that our temperatures arenât 98. 6 degrees all the time, even when we are healthy. Some peoplesâ bodies run warmer than others. Find out what your normal body temperature is so you can tell when a fever means you are sick and when it doesn’t. The same is true for snapping: we expect the amount of snapping we hear to vary between healthy stretches of shallow water. So, we need to know what’s normal for each of them before we can say if less snapping means habitats are being damaged.
For a few years, as part of the SanctSound project, we’ve been listening to national marine sanctuaries across the country at night. Four of the places we checked had a lot of snapping shrimp. These were the Florida Keys, Gray’s Reef, the Channel Islands, and the Hawaiian Islands Humpback Whale national marine sanctuaries. Our measurements were all the same because we used the same automated tool to count how many snaps happened in each of these spots. We saw different amounts of snapping in these places, and the amount of snapping changed throughout the day and year.
When we put all of our recordings together, those from Gray’s Reef National Marine Sanctuary, a hard live-bottom reef habitat off the coast of Georgia, had the most snapping. Those from Florida Keys National Marine Sanctuary had the least. It’s clear, though, that the sanctuaries have different peak times for snapping. For example, the Florida Keys, Gray’s Reef, and Hawaiian Islands Humpback Whale national marine sanctuaries all had their peak snapping times in the spring, while the Channel Islands didn’t have their peak snapping times until early summer. Other studies have found that snapping happens most often when the water temperature rises above a certain level, which can happen in different places and at different times of the year.
We see that the time of day also changes how much snapping we hear by looking into the data more deeply. At Gray’s Reef and Hawaiian Islands Humpback Whale national marine sanctuaries, look at these areas of shrimp snapping. You can see that we hear more snapping during the darker hours of the day in both places. This is similar to other studies that have found that snapping picks up at dusk. But you can see that the pattern isn’t the same everywhere. In Gray’s Reef, the snapping is strongest at twilight, but in Hawai’i, it gets stronger when the sun goes down.
Pistol shrimp, also known as snapping shrimp, are a fascinating creature that produce an extremely loud snapping sound with their claws This shrimp gets its name from the popping or “shooting” noise it makes, which sounds like a tiny pistol going off underwater. But just how loud is the pistol shrimp’s snap really?
An Ear-Splitting Ocean Snap
The snapping sound produced by the pistol shrimp is one of the loudest natural sounds in the ocean The snap can reach an incredible 210 decibels! To put that into perspective, a jet engine registers at 140 decibels and a gunshot ranges from 140 to 175 decibels The shrimp’s snap is even louder than both of those!
At 210 decibels, the pistol shrimp’s snap is one of the loudest sounds produced by any animal on the planet. The intense volume is astounding considering the shrimp is only a couple inches long.
How Does Such a Small Shrimp Make Such a Loud Sound?
Pistol shrimp have one enlarged claw that is used to create the loud snapping sound. Here’s how it works:
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The shrimp opens the claw, allowing water to rush inside a small chamber.
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It then quickly closes the claw, pushing the plunger portion against the chamber.
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This forces the water out at extremely high pressure, creating a jet stream.
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As the jet hits the surrounding water, tiny bubbles are formed.
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When the bubbles collapse, it results in a loud snap.
The entire process happens in less than 1 millisecond! The shrimp can snap its claw so quickly that the bubbles reach speeds up to 60 miles per hour. This rapid cavitation is what produces the ear-piercing crack.
Why Do Pistol Shrimp Snap So Loudly?
The pistol shrimp’s powerful snapping serves several important purposes:
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Hunting: The snap stuns small fish and shrimp, allowing the pistol shrimp to capture its prey more easily. At close range, the cavitation bubbles can even kill the target.
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Defense: The loud noise deters predators and warns competitors to stay out of their territory. Larger pistol shrimp can even use their snap to break shells of small crabs or mollusks.
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Communication: The snaps are a way for pistol shrimp to communicate with each other. Males will snap more frequently to attract females during mating.
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Symbiosis: Some species of pistol shrimp form helpful partnerships with fish like gobies. The shrimp snaps to scare prey out of rock crevices while the goby catches the fleeing animals.
Not All Pistol Shrimp Snap Equally Loud
While some pistol shrimp like the tiger pistol and candy cane pistol produce incredibly loud snaps, other species are not quite as noisy.
The Randall’s pistol shrimp, for example, is one of the quieter shrimp pistol species. Its snapping sounds have been compared to clipping fingernails or breaking small wooden sticks. For aquarists who want pistol shrimp but are worried about noise, Randall’s pistol shrimp is a good option.
In general, larger shrimp tend to be louder than smaller shrimp. Older, more experienced shrimp also snap louder than younger pistol shrimp who are still learning to control their claws.
Things like the shrimp’s environment, stress level, and activity can also impact snapping volume and frequency. A stressed or threatened shrimp is likely to snap much more often and aggressively.
Hearing Pistol Shrimp Snaps in the Ocean
The loud snapping of pistol shrimp packs can actually be heard above water in certain tropical and sub-tropical coastal areas. Snapping shrimp congregate in large groups, so the combined snaps of multiple shrimp sound like crackling or popping underwater.
This background noise is known as shrimp chatter or shrimp thunder. The sounds can be heard emanating from rock crevices, coral reefs, or seabeds where pistol shrimp have burrowed.
Shrimp chatter can be so loud that submariners and SONAR operators have to compensate for the background noise. That’s quite impressive for a colony of tiny crustaceans!
Coping With Noisy Pistol Shrimp in Aquariums
The piercing snaps of pistol shrimp can be a nuisance for aquarists trying to sleep or relax. Loud snapping at night is especially problematic if the tank is kept in a bedroom.
Here are some tips for dealing with noisy pistol shrimp in home aquariums:
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Select shrimp species known to be quieter, like Randall’s pistol shrimp. Avoid large shrimp.
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Make sure shrimp are paired with symbiotic fish to reduce stress and snapping. Watch for signs of aggression.
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Provide ample hides and burrows to help shrimp feel secure.
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Feed shrimp well and maintain stable water parameters.
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Use foam or insulation around tank to muffle sounds.
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Keep tank lights off at night to encourage less nocturnal activity.
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As a last resort, trap excessively loud shrimp using bait and remove from tank.
With some basic precautions, pistol shrimp can make an interesting addition to saltwater aquariums without being disruptive. Their fascinating natural biology and behaviors are worth experiencing. Just be prepared for an occasional noisy surprise!
Frequency of Entities:
pistol shrimp: 31
snap: 24
shrimp: 20
loud: 16
water: 7
bubble: 6
aquarium: 5
noise: 5
species: 4
tank: 4
claw: 4
sound: 4
ocean: 3
goby: 3
pressure: 2
creature: 2
animal: 2
purpose: 2
snapping: 2
frequency: 1
volume: 1
environment: 1
cavity: 1
jet: 1
chamber: 1
plunger: 1
captures: 1
warns: 1
break: 1
communicate: 1
symbiosis: 1
fingernails: 1
sticks: 1
impact: 1
chatter: 1
thunder: 1
operators: 1
background: 1
burrowed: 1
seabeds: 1
reefs: 1
crevices: 1
colonies: 1
crustaceans: 1
sleep: 1
bedroom: 1
aggression: 1
hide: 1
bait: 1
precautions: 1
behaviors: 1
surprise: 1
Pistol Shrimp sonic weapon – Weird Nature – BBC wildlife
What does a pistol shrimp sound like?
The pistol shrimp cocks its distinctive claw back and “fires” repeatedly at nearby prey. Each time its claws snap, bubbles shoot forward and for a brief moment produce nearly as much heat as the sun’s surface! The sound from each claw snap is incredible, hitting 218 decibels, a noise loud enough to knock nearby animals unconscious.
How loud is a pistol shrimp claw?
The sound from each claw snap is incredible, hitting 218 decibels, a noise loud enough to knock nearby animals unconscious. The pistol shrimp is one of the most uniquely evolved predators across the natural world. Yet, even with its distinctive snapping claw, it must often rely on trusted companions for survival.
How does a pistol shrimp work?
This large claw holds the pistol shrimp’s superpower. When a pistol shrimp senses prey is nearby, it will open the top part of its big claw, allowing some water to enter a small chamber in the crook of the claw. Then, when it clamps down, the pressure from a small plunger on the top claw forces the water out of the chamber.
How many decibels does a pistol shrimp sound?
Their claws have reached a sound frequency of around 218 decibels (colonies of pistol shrimp are said to sound like heavily sizzling fat to divers). Pistol shrimps use their large claws for fighting with rivals and have reached a sound frequency of around 218 decibels.