Named for their venomous sting, scorpionfish are bottom-dwelling fish that use a combination of camouflage and patience to catch prey, sucking them into their mouth like a hungry Hoover.
Although they don’t target humans, their toxin can cause severe pain and swelling if you’re unlucky enough to get stung by accident.
What are scorpionfish?
Related to the most venomous fish on the planet (the stonefish), scorpionfish are also worth watching out for. These ambush predators don’t go after humans but an accidental sting can be very painful and – if you’re allergic – could be fatal.
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Because scorpionfish don’t go after humans, stings aren’t particularly common but their outstanding camouflage can increase the chance of getting on the wrong side of these venomous creatures. They conceal themselves so perfectly into the reef that it can be almost impossible to see them – meaning people sometimes step on them by accident.
Although these venomous fish look very similar to stonefish (and the two are often confused for each other), scorpionfish have a more defined fish-like body whereas stonefish look like a child drew a sad face on a lump of rock.
How big are scorpionfish?
They are usually around 50cm and weigh up to around 2kg
What do scorpionfish look like?
There are hundreds of species of scorpionfish, all of which sport a slightly different look. Their main goal, though, is using clever camouflage to blend in almost perfectly with the habitat around them. This means that some are dull greenish grey colours, like a rock that’s been sitting underwater collecting algae, while others are bright reds or oranges like the vibrant coral reefs where they live.
Their skin colour is often broken up with mottling or delicate patterns, which breaks up their outline and tricks the eye into making it more difficult to see the whole fish.
They also have large mouths, which play an important part in their hunting strategy – when they open them wide, it creates suction that pulls their prey into their mouth, ready to be swallowed whole.
Where do they live?
These solitary fish are usually found hanging out on the substrate or seafloor around coral or rocky reefs waiting for prey to pass by. They like tropical, sub-tropical and temperate waters and are often found in the Indo-Pacific and Atlantic oceans.
What do they eat?
Scorpionfish typically eat small fish, crustaceans and other invertebrates.
How do scorpionfish hunt?
Rather than expend lots of energy on chasing prey, scorpionfish just wait for their dinner to come to them. Their camouflage and ability to sit almost motionless on the seabed enables them to blend seamlessly into their surroundings. They can be so well hidden that their prey has no idea there’s a threat in the water and swims right into the danger zone.
When the time is right, these ambush predators strike by expanding their large mouths to create a vacuum that sucks their helpless prey in. Terrifying!
How do they reproduce?
When they’re ready to reproduce, scorpionfish release their eggs and sperm into the water to be fertilised. In some species, the gelatinous egg masses are jelly-like blobs that float to the surface where they are less likely to be eaten by potential predators.
How long do scorpionfish live?
Their average lifespan is around 10 to 15 years
Are they dangerous to humans?
Yes, they can be. Scorpionfish can deliver a toxic venom that can cause pain, swelling, difficulty breathing and heart issues if you get stung.
Deaths are rare but can happen if someone is allergic to the venom. This is – almost – what happened to Rod Lawson who was stung by a scorpionfish while trying to untangle it from a windsurfing line while on holiday in Rhodes. Thankfully, despite his rare allergy, medics were able to save his life.
Lawson was rushed to hospital after his arm had swollen to a terrifying size. “It was like an elephant’s trunk – four times its original size from the fingers right up to the armpit,” he told the Times and Star in an interview.
Like their relative the stonefish, which is thought to be the most venomous fish in the sea, scorpionfish do not actively attack humans. Their venomous spines are for self defence so stings usually happen when someone accidentally stands on them or handles them, for example while removing them from a fishing line.
Are they under threat?
There are many different species of scorpionfish and, although not all have been included on the IUCN Red List of Threatened Species, those that have are considered species ‘of least concern’. They may still be impacted by local threats such as pollution and habitat destruction.
