Andrew took the time the other day to point out the blog about the Glaucus atlanticus slug. While that creature is pretty cool, I’m here to argue the merits of the pistol shrimp as the best sea creature. You may be thinking “How could anything possibly beat a slug that eats poison for lunch?”  The answer to that is simple: a shrimp who can paralyze its pray with a bubble that flashes like the sun.

Alpheus Heterochaelis

The proper name for the pistol shrimp family is Alpheus heterochialis, but they also go by  the names snapping shrimp and alpheid shrimp. For the purposes of this article, I will be referring to the species as the pistol shrimp, simply because I like that name best. Despite its tough guy name, the shrimp is very small and  only grows to be about 2-3 inches long. Don’t judge a book by its cover though, because the pistol shrimp is more powerful than it looks.

Take a look at the picture above. Why on earth is one claw significantly bigger than the other? Maybe to scare off predators or attract a mate? Turns out this claw creates one of the loudest noises in the ocean.  That noise is the sign of something truly amazing happening.

Stun Gun-How it Works

The pistol shrimp is a little different from your typical shrimp in its claw design.  The bigger claw isn’t used for pinching or claw-to-claw combat, but instead is a sophisticated biological weapon. The claw is able to lock, much like the hammer of a gun, and release extremely quickly creating a bang and a stun gun effect. The snap of the claw actually creates a jet of water that moves up to 62 miles an hour. This action creates a bubble that ends up imploding on itself creating a very loud crack and briefly creating sonoluminescence. Essentially, the temperature inside the collapsing bubble is around 18,000 degrees Fahrenheit for less than 300 microseconds.

Pistol shrimp are named very aptly, not only for the way they stun, with the “water bullet” we looked at above,  but also the sound they produce while doing so. The bubble collapsing on itself  creates a 218 decibel sound. To give you some comparison, a real gunshot comes in at about 140 decibels. That’s right, the shrimp can actually be louder than a gun. And that ladies and gentlemen, is how a 2 inch shrimp competes with whales for the title “Loudest in the Ocean.” This can create a few problems for humans in the ocean, which will be discussed later in the blog.

What it Does for the Shrimp

Why does a little shrimp need such a powerful weapon? It’s is for the same reason most animals need a weapon: Food. The pistol shrimp is able to use its unique biological talents to stun its prey, or even in the case of a small fish, kill it. The shrimp then comes out from its hiding spot, drags its prey back to safety to eat in peace. In this way, the shrimp is able to kill its prey and eat it while still staying close to its predator-proof burrow. No claw-to-claw combat for this little guy!

Symbiotic Relationship with the Goby

As if the pistol shrimp weren’t cool enough, it even has a best friend in the Goby fish. The Goby fish has excellent eyesight and will keep an eye out for predators for the pistol shrimp. In return, the pistol shrimp will make the Goby a home and kill food for it. Together these two live in a nice symbiotic relationship.

Shrimp-The Cloaking Device You Never Thought Of

Pistol shrimp can be both a benefit and a distraction to ocean going humans. For divers and people trying to record underwater noises, the din from the shrimp can be extremely annoying, especially when a whole colony is there. Even more interesting (at least for me) is the fact that submarines have been known to hide among beds of pistol shrimp to avoid sonar detection. The sound interference prevents the sonar from being able to find the submarine. It’s certainly a unique way of avoiding detection!

Where Can I Find a Pistol Shrimp?

You can find pistol shrimp in many different places in the ocean, but the one place you can’t find them is in your standard aquarium. Pistol shrimp are too difficult to keep in an enthusiast’s aquarium because they have a nasty habit of using their bubble bullets to shatter the tank glass. Obviously that is a major problem for everyone involved. If you are desperate to find a pistol shrimp, take a look in the shallow waters of some of the world’s tropical and subtropical waters. Coral reefs, seagrass, and oyster reefs all provide excellent habitat for the little gunslingers.

Why Does this Matter?

You may be asking yourself “What on earth does a shrimp have to do with me?” and the short answer is that it probably won’t ever affect your life directly. But the shrimp still presents some important challenges to think about. First is that as smart as we think we are, humans are not the first animals to use the gun as a weapon. This little innocuous shrimp has been doing it long before we have. Second, it’s interesting to look at because it shows the power of implosion. One little shrimp can briefly make a flash of light as hot as the sun just by using the natural pressures released from the claw snap. Imagine if something like this were to happen on a larger scale and how devasting to our way of life it has the potential to be. Still not convinced this shrimp is relevant? Think about the submarine issue. What if we could hide our submarines from enemy detection by using colonies of pistol shrimp? It may sound far fetched, but if it could be made feasible, sonor detection could become seriously impaired. Quite simply, the pistol shrimp matters because we can learn from it and the research done on it. While it’s a stretch to say something learned from the pistol shrimp might make a significant difference in your life, its not impossible.

I tried my very best to explain the pistol shrimp, but I highly recommend this video to really get a feel for what they do.

 

What do you think of the pistol shrimp? Does it beat the poisonous slug in your eyes? Do you prefer the shrimp’s other names? Are you convinced this shrimp is cooler than you? Let me know in the comments below.

That’s all for now.

Meghan

One last fact- If for some reason the shrimp loses its pistol claw, the other smaller claw will grow into a pistol claw to replace it. The former pistol claw will regrow as the smaller claw.