Thank you so much for sharing this vivid (and totally relatable) nighttime encounter in the bathroom! That bang against the lamp is unmistakable – and yes, it really does make you jump.

You've already done half the work by figuring out it's not a cockchafer. Let me confirm your identification, explain why it was in your bathroom, and—most importantly—tell you what to do (and what not to do) if you find another one.

✅ First the good news: The May beetle is harmless to you.

First, take a deep breath. The cockchafer (  Melolontha melolontha ), sometimes also called "May beetle" or "Doodlebug", is neither dangerous  to humans nor to pets  .

  • It doesn't bite or sting.   The pincers on its head? They're for eating plant leaves, not for pinching people.

  • It is non-toxic.   No poison, no irritation.

  • It doesn't infest houses.   It's an insect that lives outdoors and accidentally flew into the house because it was attracted by the light in the bathroom.

So why did it choose your bathroom in particular? You've probably already guessed:   light  .

🪲 Why was it in your bathroom?

May beetles are nocturnal and strongly attracted to light sources – especially white or bright light. The light in your bathroom, reflected off the shiny tiles and porcelain, acted like a beacon.

They also appear in late spring (April–May) for their short flight period as adults, which lasts only 4–6 weeks. During this time, the males fly noisily at dusk and into the night in search of females. This is when they are most likely to accidentally fly into a lit room through an open window or even down a chimney.

Her bathroom offered all the ideal conditions:

  • A bright light burns at night. ✅

  • An open window or a gap around a ventilation opening ✅

  • Warm, humid air (which they find inviting) ✅

He wasn't looking for a new home. He was simply lost.

You mentioned that you initially thought it was a cockchafer. This is a very common mistake. Here's the short version:

Characteristics May beetle June beetle
Size Larger (1–1.5 inches / 25–35 mm) Smaller (½–1 inch / 12–25 mm)
Color Dark reddish-brown with a black head Shiny, metallic greenish-brown
Movement Clumsy, noisy, bumps into things Buzzing, unpredictable, but somewhat more agile
Active season Late April to May (only 4–6 weeks) Late May to June
Body shape Stockier, more oval Somewhat slimmer
The May beetle is also much louder in flight—hence the disconcerting "slapping" sound you heard. They are not graceful fliers at all.

🛠️ What to do if you find one (What you did exactly right):
You did that perfectly. Here's the simple step-by-step guide:

1. Don't panic! They can't hurt you. Even if one lands on you, it will just crawl or try to fly away.

2. Turn off the bathroom light and close the door. The darkness will calm it down, and it will stop banging on surfaces.

3. Open a window (if possible) and turn on an outside light. The animal will fly towards the light and then fly away on its own. This is the gentlest method.

4. Alternatively, you can carefully catch it. Use a cup and a piece of sturdy paper or cardboard. Slide the paper under the cup, carry it outside, and release the animal on a tree or bush (not directly on the ground – it needs to be able to climb).

What you should NOT do:

Do not crush (that's messy and unnecessary).

Please do not throw it down the toilet (it is alive and can survive in the pipes for a while – cruel and ineffective).

Do not spray it with insecticides in the bathroom (this is excessive and introduces chemicals into your living space).

🏠 Will more cockchafers be coming into the house?
Read more on the next page.Probably not. The flight period of the adult moths is very short (4–6 weeks). You might find one or two more stragglers if you leave the bathroom light on at night with the windows open. However, they   do not breed or nest   in your house. For their larval stage, they need soil and plant roots, which your bathroom does not provide.

If you want to avoid future confusion among your visitors:

  • Keep bathroom windows closed or fitted with fly screens on May evenings.

  • For lights near open windows, use a lower wattage bulb or a yellow insect lamp.

  • During May beetle season, switch off unnecessary lights at night.

🌍 Final remark: May beetles are actually beneficial for the garden.

Adult cockchafers eat leaves (which can annoy gardeners). As larvae, however, they loosen the soil and decompose organic material. More importantly, they are a vital food source for bats, birds, and hedgehogs.

Their population collapsed in the 20th century due to pesticides. But they are slowly recovering, and many ecologists see this as a positive sign for biodiversity. So their nocturnal visitor wasn't just a clumsy insect – it was a small indication that local ecosystems are recovering.

🗝️ Conclusion

AskAnswer
Is it dangerous?No   – safe for humans and animals.
Will it bite?No   – it has no interest in you.
Is my house infested with pests?No   – it was a single, lost adult.
Should I call a pest control service?No   – it is an insect that lives outdoors, not a pest.
What do I do?Turn off the light, open a window, or carefully slide the object outside in your hand.

You survived an encounter with a cockchafer. That's not bad luck. It's also not a sign of an unclean home. It's simply one of nature's clumsiest, loudest, and most harmless spring visitors that got lost and headed straight for your toothbrush.

And quite honestly? That's a much better story than "I found a cockroach".

If you see another one tonight, smile, turn off the light, and let it find its way back outside. You can do it! 🪲