Weever fish: the worst thing on an Irish beach, and it is smaller than your hand

Nothing in Irish water will do you as much harm for its size as a lesser weever. It is about the length of your finger, it is buried in the sand where you are about to put your foot, and people describe the sting as one of the worst pains they have had. This is not a Kilkee problem — it is worth knowing on any sandy beach in Ireland.

What it is and where it is

Echiichthys vipera, the lesser weever. A small sandy-coloured fish that lies buried in shallow sandy ground with nothing showing but the spiny first dorsal fin. That fin carries three venomous spines. It is not aggressive and it is not hunting you — it is a defensive animal that you stand on.

It wants clean sand in shallow water, so the beaches people actually swim off are exactly the ones it lives on — the west coast strands, the Kerry and Clare beaches, the south coast, Dublin bay, Donegal. Anywhere you can walk out on soft sand, assume they are there.

Two things decide when you meet one. They are commonest around the Irish coast from May to September as the water warms, and they come closest to shore at low tide. Low water on a warm afternoon in July is the exact combination to watch.

What it feels like

Immediate, severe, and out of all proportion to the mark on your foot. Intense pain building over the first hour, swelling, and often numbness spreading through the foot. Less commonly people get dizziness, nausea or vomiting, and occasionally someone faints. It is frightening the first time, largely because the pain is so far beyond what a puncture that small ought to produce.

The treatment that works

Heat. The venom is made of proteins that break down when they get hot, so hot water immersion is not folk wisdom — it is the actual mechanism.

• Get the foot into hot water as soon as you can. Hot, not scalding — 45 degrees is the upper limit.

• Keep it there. Thirty to ninety minutes, or until the pain genuinely eases. People give up far too early and the pain comes straight back.

• Top it up as it cools, testing the temperature each time.

• Check for a broken-off spine in the wound, and keep it clean afterwards.

The mistake nobody warns you about

The sting numbs the foot. That means the person in agony is the worst possible judge of how hot the water is, and there are documented cases of people giving themselves a serious scald on top of the sting because they kept adding hot water to a limb that could no longer feel it.

Somebody else tests the water, with an elbow or a hand that has not been stung. Every time it is topped up. That one habit prevents the second injury.

Never let the stung person judge the water temperature. Their foot is numb. Someone else tests it, every time.

When it needs a doctor

Most stings are handled with hot water and patience. Get medical help if there is a spine left in the wound, if pain or swelling is still severe after a couple of hours of proper treatment, if the person has trouble breathing or a strong whole-body reaction, or if the wound looks infected over the following days. For anything serious, ring 112 or 999.

Not getting stung in the first place

Wear something on your feet in shallow sand at low tide — old runners, wetsuit boots, anything. Shuffle rather than stride, so a buried fish feels you coming and leaves. And be particularly careful in the last hour before low water on a warm summer day, which is when the two risk factors line up. That advice holds on every sandy beach in the country, not just ours.

Tide times for Kilkee are on our home page. If someone in your group gets stung and you are near the East Pier, call in — we would far rather sort it out properly than have you drive home with a foot in a cold towel.