What Deadly Animals Should You Watch Out For In UK Seas?


While the UK isn’t as renowned as Australia for its deadly creatures, a quick swim in the sea can turn nasty very quickly if you encounter one of these creatures…


These fish are approximately 30 cm in size and are commonly found in the North Sea and the Atlantic. In particular, one species called ‘Lesser weevers’ are of greater risk to humans as they reside in the sand of shallow waters and sometimes damp sand. Weevers have venomous spines on their back and gills which injure people who accidentally step or sit on them. At first, it may feel like a small cut, but the pain worsens over time and can become severe. The pain should subside within 12–24 hours but may require medical treatment if the victim suffers from pre-existing medical conditions or if part of the spine breaks off in the wound.

UK location: All around.

Portuguese Man O’War

Commonly mistaken for a jellyfish, the Portuguese Man O’War can be blown into UK seas by strong westerly winds. While the purple aquatic creatures may look remarkable, their tentacles have strong stinging cells which can cause immense pain to unsuspecting swimmers. While some people can treat a sting at home, medical care may be required depending on the reaction and if some tentacles remain on the skin. Even if the creature has been washed onshore, their tentacles can continue to sting.

UK location: Primarily found on the UK West Coast, Cornwall and the Isles of Scilly.


The common stingray is the species found in shallow British waters at a depth of less than 60 m. They are generally timid creatures found in shallow waters, using their stinging tail as a defensive mechanism when threatened. The stinger releases venom into the victim which can cause moderate pain and sickness. If part of the stinger is stuck inside the wound, medical attention is required to remove it. The sting can be fatal if it hits the face or chest.

UK location: All around.

Sea Urchins

Several spiky species of sea urchins are commonly found on rocky British shores. Problems occur when beach goers step on the urchins and the creatures’ hedgehog-like spines puncture humans. Their spines can be venomous and may cause respiration problems. Like many of the animals on this list, the spines can become embedded in the wound causing further damage.

UK location: All around, rocky coasts.


There are various noteworthy jellyfish species found in UK seas; one is Lion’s mane jellyfish. As one of the largest jellyfish, the tentacles alone can be up to 3 m long, covered in painful stinging cells. While not normally fatal, the sting can be painful. Any embedded tentacles should be removed (not with your bare hand) and washed with vinegar and warm water.

UK location: Most coasts during summer.

The symptoms of these injuries can range from moderate pain to paralysis and in extreme cases death, depending on the victim’s health and reaction, but the outlook for these stings and wounds are mostly good. The good news is most of these damages are avoidable by wearing shoes, being cautious, and appreciating wildlife from a distance.



Leave A Reply