Like a grenade painted with a cartoon frown, the lesser weever fish reclines with quiet malice just below the low water mark on sandy, muddy or light shingle shores.
Half buried in sea bed sediment, with a pretty golden body and a preposterously sour expression, it is unknown to the crowds sunbathing and reading on the beach – until they step too close.
What are weever fish?
Weever fish are a type of venomous fish that spend most of their lives buried in the sand.
How painful are weever fish stings
To tread on a weever fish is to taunt a tiger: inch-long dorsal spines stab the offender, whose foot soon swells like a red balloon. Dunking the limb in extremely hot water helps break down the toxins, but the swelling can last for days. Distrust of the seaside might linger longer.
Weever fish are the stinging nettles of the sea, primed and armed at all moments for heavy-hitting self-defence. The sting is rarely dangerous, but howls and tears from its victims are testament to its extreme pain.
The venom is in fact tailored to agonise: with some of the highest levels of serotonin known from any animal, it sets nervous systems aflame. But its potency does have an upside; it is being studied for its potential to kill cancerous cells. And it also gave the fish its name. Weever is derived from Old French for viper.
How big are weever fish?
It may surprise sting victims to learn that their foe is only about the size of a house sparrow. Offshore, a second, larger species – the greater weever – wanders, but it is the smaller fish that dwells close to beaches, nestled in the sand with only its large eyes and sulky mouth poking into the water.
They can be found anywhere on the coast where the seafloor is suitable, although Scotland has fewer records than the rest of the British Isles. Unluckily for us, lesser weevers are most inclined to approach the shore in summer.
How do weever fish hunt their prey?
Of course, this fish has a motive for lurking near beaches, and it has little to do with wilfully upsetting humans. Weever fish have no swim bladder – they do not naturally float, and their ambush habits serve them well. They spend their days snapping at any small fish or prawns that stray too close, but their nights are more lively; perhaps hunting is safer when shags and grey seals are asleep.
How long do weever fish live?
With their spines, slow growth rate and cautious habits, weever fish can live well – if still with a miserable expression – for 15 years.
