If you like mantis shrimp, you’re going to love pistol shrimp. And unlike their punching pals, these guys are actually shrimp!
Whereas mantis shrimp are known for their powerful punches, the pistol shrimp deals its fatal blow with only a single pincer, albeit a large one. When the pistol shrimp spots potential prey wandering by, it pops this big pincer (called the snapper) at it. The snapper launches a little stream of water at a speed of 105 feet per second, which rapidly decreases the water pressure to create bubble bullets. The bubbles immediately burst as the water pressure suddenly returns to normal, creating an insanely loud click of 210 decibels and briefly heating the surrounding water to a whopping 8000°F.
Unsurprisingly, this typically kills the pistol shrimp’s prey instantaneously, or at least knocks it unconscious.
Pistol shrimp don’t just use their bubble bullets for hunting. Some species use them to dig their homes out of rock. Allow me to reiterate – the pistol shrimp can break apart rock with its bubble bullets. Maybe we should call those projectiles bubble grenades instead.
Fortunately for anyone wanting to steer clear of grenade-launching crustaceans, those loud bubbles are pretty easy to hear when you’re swimming near their coral reef home. The constant noise from pistol shrimp colonies actually interferes with sonar equipment, but can also be a tell-tale sign of coral reef health: the louder the noise, the better shape the reef ecosystem is in.
Despite their intimidating abilities, pistol shrimp are actually pretty good at making friends. Some pistol shrimp will let goby fish live with them, and even share food with their vertebrate roommates. Although it doesn’t pay rent, the goby fish does earn its keep by keeping an eye out for predators – if the goby spots danger, it’ll signal the pistol shrimp with its tail, and they’ll escape back to their burrow together. Pistol shrimp may also make their home amongst coral and fight off hungry coral-munching crown-of-thorns sea stars, or form pistol shrimp colonies inside clusters of sponges.
Like most crustaceans, the pistol shrimp may lose a pincer from time to time competing against other pistol shrimp or escaping predators. Fortunately, these pincers will grow back, but the method for re-growing the snapper is kind of interesting: rather than regrow its pistol on the same side of its body, the lost limb will actually grow back as a regular pincer, while the remaining pincer develops into a new snapper. I suppose that means the shrimp would get its snapper back faster than if it waited for an entirely new arm to grow back, which is a good thing, because a pistol shrimp without its pistol is like a wolf without its teeth.
I wonder who’d be quicker on the draw, a mantis shrimp or a pistol shrimp? Those vibrantly-hued crustaceans pack a fast punch, but pistol shrimp don’t have to make contact with their opponent… it’s definitely interesting to think about.
Either way, I’m still glad both these guys are stuck in the ocean. Imagine if we had pistol scorpions… yikes.