The Pistol shrimp or Snapping shrimp is an impressive, unique, and desirable marine invertebrate. Its snapping claw, called “the Pistol,” makes a loud noise and has a lot of force that can knock out small insects and fish.
There is a small animal called a Pistol shrimp that can live in a saltwater aquarium. Most types of Pistol shrimp are reef-safe, meaning they can live with corals and fish that don’t attack them. They are also pretty easy to take care of.
If you want to learn more about how to care for Pistol shrimp in a tank, this article is a great place to start.
Pistol shrimp are fascinating creatures that inhabit reef tanks and capture the imagination of aquarists with their incredible snapping claws. But what do these marine invertebrates actually eat? In this article, we’ll take an in-depth look at the pistol shrimp’s diet and feeding habits.
Pistol shrimp belong to the genus Alpheus in the family Alpheidae. They are called “pistol” shrimp due to their enlarged snapping claws that can create a loud “popping” sound, similar to a gunshot This snapping claw can shoot out a high-velocity jet of water capable of stunning or killing prey
There are over 600 species of pistol shrimp, but some of the most popular in the aquarium trade include:
- Tiger pistol shrimp
- Randall’s pistol shrimp
- Candy cane pistol shrimp
Pistol shrimp have poor eyesight. Instead they rely on their antennae to sense vibrations in the water. Many species form symbiotic relationships with goby fish who act as “watchdogs” and alert the shrimp to danger.
In the wild, pistol shrimp excavate burrows in sandy or muddy substrates near coral reefs. They are found throughout tropical and subtropical oceans around the world.
Pistol Shrimp Are Carnivores
Pistol shrimp are primarily carnivorous and get most of their nutrition from animal matter. They use their snapping claws not only for defense but also to stun and kill prey.
Some of the main components of a pistol shrimp’s diet include:
- Small crustaceans – shrimp, crab larvae, copepods
- Worms – polychaetes, bristle worms
- Mollusks – snails, limpets, small clams
- Fish larvae and eggs
- Zooplankton – amphipods, isopods, ostracods
- Detritus and algae
Pistol shrimp are opportunistic feeders and will eat whatever small meaty foods they can capture with their claws. In the aquarium, they should be fed a varied meaty diet including frozen mysis shrimp, brine shrimp, crab, clam and mussel.
How Pistol Shrimp Hunt and Kill Prey
Pistol shrimp employ an ingenious mechanism to hunt and kill prey using their snapping claw. Here’s a look at how it works:
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The shrimp spots potential prey, such as a small crab or worm.
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It opens its enlarged snapping claw and then quickly closes it, creating a high-velocity water jet.
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This jet of water is forced out at speeds of up to 60 mph. The resulting shock wave stuns or kills the prey.
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The collapsing cavitation bubble from the jet also produces a loud “pop” ranging from 218 to 226 decibels! This is one of the loudest sounds produced by any marine animal.
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The stunned prey is then retrieved and consumed by the pistol shrimp.
The shrimp’s deadly claw shot is extremely accurate within a distance of about 1 cm. They preferentially hunt slow moving or sessile prey which is easier to capture.
Pistol Shrimp Have Varied Feeding Behaviors
Pistol shrimp exhibit some interesting behaviors when it comes to finding and eating food:
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Nocturnal feeding – Pistol shrimp do most of their hunting at night and hide out in their burrows during the day. Setting up moon lights can help feed them after lights out.
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Scavenging – They will act as detritivores and scavengers if animal matter is scarce, eating bits of debris and algae in the tank.
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Burrow sharing – Symbiotic pairs may hunt cooperatively and share food within their shared burrows.
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Goby feeding – In some partnerships, the shrimp goby may collect and deliver food to the burrow to share.
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Cannibalism – Larger pistol shrimp may sometimes eat smaller members of their own species if hungry.
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Hand feeding – It is possible to hand feed pistol shrimp once they are acclimated. Use tongs to deliver small pieces of meaty foods.
What to Feed Pistol Shrimp in an Aquarium
Pistol shrimp should be offered a varied carnivorous diet in the aquarium. Here are some of the best options:
- Fresh, finely chopped seafood – shrimp, squid, mussel, clam
- Frozen foods – mysis, brine shrimp, cyclops, fish eggs
- Freeze dried plankton
- Meaty pellets or flakes
- Live brine shrimp or blackworms
For reef tanks, the shrimp can also pick at reef plankton, amphipods and other microfauna produced in a mature tank.
Ideally, pistol shrimp should be fed once or twice a day. Target feed the shrimp by dropping pieces of food directly in front of their burrows using a pipette or turkey baster. For shyer individuals, turn off the aquarium lights and feed at night.
Soak freeze dried foods in tank water prior to feeding to rehydrate. Only feed as much as the shrimp can eat in a few minutes and remove any uneaten leftovers to avoid water quality issues.
What Not to Feed Pistol Shrimp
Avoid offering pistol shrimp the following:
- Flake foods with lots of plant matter/fiber
- Terrestrial meats like beef heart
- Overfeeding – leads to high nitrates
Copper medications should never be used in tanks with pistol shrimp or other invertebrates as copper is toxic.
Potential Dietary Issues
Here are some potential problems to watch out for with a pistol shrimp’s diet:
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Starvation – Shrimp may starve if they cannot find enough meaty foods in the tank. Target feed if needed.
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Overfeeding – Excess uneaten food pollutes water. Only feed amount shrimp will consume.
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Aggression – Very hungry shrimp may attack tankmates. Keep well fed.
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Bloating – Can occur if overfed or fed foods that expand in water.
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Cannibalism – Hungry shrimp may turn on each other if not fed enough.
The Takeaway
Behavior of Pistol Shrimp
Pistol shrimp will make a great place to hide by digging holes in the substrate, which is where they will spend most of their time.
You should be careful keeping them in the same tank as smaller fish and invertebrates, even though they are very shy animals.
The shrimps come out at night and like to spend the day in dimly lit areas. They will dig under rocks and eat food that has been left out in the open areas of your reef tank whenever they want to.
They clean up the area around their sandy burrows and inside their burrows because it’s a chore for them. Being scavengers makes it a lot easier for them.
Snapping shrimps are socially monogamous and territorial. In some situations, the Pistol shrimp may act mean toward other fish in the tank, but each species has a different personality. Varieties from the Carribbean tend to be more aggressive than many other species. They also like to be left alone, because if someone bothers them or their host, they will attack without hesitation.
Whenever it is needed the pistol shrimp can be a superb hunter. It detects nearby preys with its antennae and immobilizes them with the aid of the snapping claw. This claw is a defense mechanism that can knock out or kill small fish, shrimp, starfish, and crabs. It can also keep big predators from attacking.
Another distinct behavior observed amongst Pistol shrimps is the communication between individuals using snaps. Along with chemical signals, they use the frequency and speed of the water jets that the snaps send out to send information.
Interesting fact: A genus of Pistol shrimp, Synalpheus, forms colonies containing hundreds of individuals and live inside sponges. This is the only genus that has social behavior.
This advanced social organization amongst organisms is known as eusociality. Here, the colony formed is ruled by a large single breeding female (the queen) and a reproductive male. Males make up most of the castes. They are divided into workers who take care of the babies and soldiers who protect the colony from outside threats.
The Pistol shrimp is renowned for its powerful snapping ability. Basically, the shrimp utilizes its large claw as a communication tool and a weapon. When the claw quickly closes, it makes a loud snapping sound that is said to be one of the loudest sounds in the ocean.
To give you an idea, the average roar of a lion is about 115 decibels, and the sound of a jet taking off is about 150! The Pistol shrimp snap produces an incredible 210 decibels underwater.
Interesting fact: The US used the sound of pistol shrimp colonies as a sound screen to hide their submarines during the Second World War!
The high-speed water jet (which can reach about 100 km/h) is made when the plunger hits the socket. This high-velocity water jet forms tiny bubbles that can implode within a very short time. The resulting force or shockwave is capable of stunning a prey or even killing it instantly.
Researchers have found that the sonoluminescence (flash of light) that happens when the cavitation bubble bursts is actually very hot, about 5,505 degrees Celsius, which is about the same temperature as the sun.
The snap makes an intense flash of light that lasts for about 300 picoseconds to 10 nanoseconds and can’t be seen with the naked eye.
Pistol Shrimp and Compatible Tankmates
Keep in mind that different species of Pistol shrimp can get along with different types of shrimpgoby. For example, the Randall’s and Tiger Pistol shrimp can get along with many types of shrimpgoby without any problems.
Interesting Facts: The study says that more than 30 species of this genus of shrimp live together in this way. Biologists said that a porcellanid crab (Pachycheles rudis) can be a third partner in relationships between shrimp (Betaeus setosus) and gobies.
They often use a signal system, consisted of antennal contact of the shrimp with the fish and tail undulations by the fish (Watchman gobies). If the fish indicates danger by fluttering the caudal fin or even by fleeing into the tunnel the shrimp rapidly retreats.
Some species, like the Red Carribbean Pistol, don’t like living with gobies; instead, they’d rather live with the Curlycue Anemone, which is a type of Caribbean anemone with long tentacles that spiral around.
The rare Pocillopora Pistol shrimp is known to dwell within colonies of Pocillopora corals. So, no matter what kind of pistol shrimp you choose, try to have the animal that they like to eat in your reef tank.
| Pistol shrimp species | Compatible Associations |
| Tiger Pistol Shrimp (Alpheus bellulus) | Cryptocentrus cinctus, Amblyeleotris guttata, Amblyeleotris randalli or Stonogobiops yasha. |
| Randall’s Pistol Shrimp (Alpheus randalli) | Stonogobiops, Cryptocentrus, and Amblyeleotris species. |
| Fine-striped shrimp (Alpheus ochrostriatus) | C. tangaroai, A. guttata, A. randalli and A. wheeleri |
| Red Caribbean Pistol Shrimp (Alpheus sp.) | Do not usually pair with shrimpgobies. Instead, they form a relationship with the Curlycue Anemone (Bartholomea annulata). |
| Bullseye Pistol Shrimp (Alpheus soror) | Does not usually form a bond with shrimpgobies. Some individuals may share a cave with some gobies, but it is not safe for the last. |
You should lean towards the introduction of tankmates that wouldn’t harm the shrimps e. g. small fish that aren’t aggressive, corals, and sponges. Predatory fish like triggerfish, puffers, groupers, lionfish, and hawkfish, on the other hand, should not be kept together.
Do not keep the Pistol shrimp and the Mantis shrimp together. The Mantis shrimp is a large predator. Depending on the species, their size can reach up to 15 inches (35 cm).
In addition, besides the shockwave, they can also deal a lot of physical damage. This means that the mantis shrimp will usually win this fight with the pistol shrimp because it is stronger.