Pistol Shrimp
A 3cm shrimp that stuns prey by snapping a claw so fast it creates a sound louder than a gunshot and a flash of plasma
No photo available for Pistol Shrimp
Superpower
The pistol shrimp snaps its enlarged claw shut in under 1 millisecond, ejecting a water jet at 97km/h that creates a cavitation bubble reaching 8,000°C as it collapses — briefly the same temperature as the surface of the sun. The collapse generates a flash of light (sonoluminescence) and a shockwave measuring up to 218 decibels — louder than a gunshot. The pressure wave stuns or kills prey up to 4cm away before the shrimp makes physical contact. This happens in less time than a human blink.
Overview
There are over 600 species of pistol shrimp (family Alpheidae) found in tropical and subtropical marine environments worldwide. Most are less than 5cm long. Despite their size, colonies of pistol shrimp collectively produce so much snap-noise that they are one of the dominant sound sources in shallow tropical ocean — their collective snapping creates a crackle that makes sonar systems effectively unusable in areas they inhabit and was used during WWII to hide submarine signatures in the Pacific. Many species live in symbiosis with goby fish — the shrimp excavates and maintains a burrow while the nearly-blind goby keeps watch, touching the shrimp's antenna with its tail fin to signal danger.
Found in
Shallow tropical and subtropical marine environments worldwide — coral reefs, seagrass beds, and estuaries. Most numerous in the Indo-Pacific. Also found in the Mediterranean and Atlantic.
Things worth knowing
- 1
During WWII, US Navy submarines would position themselves in Pacific pistol shrimp colonies — the crackle of thousands of snapping claws masked the sub's acoustic signature from Japanese sonar operators. The shrimp's noise created natural acoustic camouflage.
- 2
The flash produced by cavitation bubble collapse (sonoluminescence) in a pistol shrimp snap lasts less than a nanosecond — it can only be photographed with specialized equipment and was confirmed in pistol shrimp specifically in 2001.
- 3
The snapping claw is used almost entirely for stunning prey and territorial combat — feeding is done with the normal-sized second claw. If the snapping claw is lost, the remaining normal claw begins growing into a snapper, and the regrown claw becomes normal.
- 4
Pistol shrimp–goby pairs are so well-studied that researchers have documented individual pairs persisting for multiple years, with the goby and shrimp appearing to recognize each other individually and coordinate defense responses.
- 5
Some pistol shrimp species are eusocial — living in colonies with a single reproductive queen, non-reproducing workers, and soldier castes, making them the only marine crustacean with a fully eusocial structure outside of the decapods.