Ouch, What Did I Just Step On? The Rise of Weever Fish Indicates a Human-Caused Imbalance in the Sea

At the Emergency Clinic in Grenaa, Denmark, a conversation about the venomous weever fish takes place almost daily. The clinic regularly treats tourists and anglers who have been stung by this fish, and currently, the numbers are higher than usual.

Just 20 kilometers away at Bønnerup Beach, there’s more evidence of the weever fish’s proliferation. At the Ny Form store, the third best-selling product is a protective foot covering designed to shield against the weever’s three spines. Store manager Pia Christensen reports a significant increase in sales, with one type of beach shoe seeing a 600% rise and another a 300% increase in just three weeks. Tourists and locals alike are purchasing these shoes due to the abundance of weever fish.

The weever fish are particularly prevalent in the Kattegat Sea, where they bury themselves in the sand in the shallow, warm water. This makes them practically invisible to beach-goers, increasing the risk of stepping on them.

Regular swimmers Poul Havshøj and Ulla Jakobsen, who bathe at Grenaa Beach year-round, always wear water shoes for protection. Jakobsen has had a personal experience of stepping on a weever fish, describing the sting as extremely unpleasant, but the pain subsided after her foot was immersed in warm water for half an hour.

The overabundance of weever fish in the Kattegat Sea is a consequence of our actions, according to Henrik Carl from the Natural History Museum of Denmark. He attributes this imbalance in the sea to overfishing of other species and global warming, which has warmed the seas, providing an optimal environment for the heat-loving weever fish.

While in the long term, efforts should be made to restore the balance of predatory fish in the sea, Carl suggests a short-term solution: eating the weever fish, which he describes as an excellent food fish.

If stung by a weever fish, the immediate response should be to immerse the affected area in hot water until the intensity of the pain subsides. It’s also advised to have a tetanus booster if your vaccination is more than 10 years old. Although the sting is not life-threatening, unless you are allergic, it is painful and unforgettable.

Carl also reassures beach-goers that wearing water shoes significantly reduces the risk of being stung by the weever fish. He advises people not to let the presence of these fish deter them from enjoying a swim in the sea.