Harlequin Ladybirds in the House: Why They Appear in Winter

A close-up illustration of a Harlequin ladybird (Harmonia axyridis) “doing its thing”: exploring a leaf edge in soft winter sunlight, wings slightly open, tiny legs gripping the surface.

This week I discovered a little cluster of unexpected visitors tucked into my bathroom curtains a mix of black and orange-black ladybirds. After a closer look, they turned out to be Harlequin ladybirds (Harmonia axyridis), an invasive species that often seeks warmth indoors at this time of year.

Why They Come Inside

As winter arrives, Harlequin ladybirds begin searching for sheltered places to hibernate. They are especially attracted to:

• Warm rooms, south-facing windows

• Curtains and fabric folds

• Bathrooms where humidity is stable

• Quiet corners where they can cluster undisturbed

Homes offer the exact conditions they seek, which is why they sometimes appear in surprising numbers.

A harlequin ladybird explores a frosty leaf, transitioning from the warmth of a cozy home to the crisp, chilly outdoors.

A Species of Many Colours

Harlequins are unusually variable. They can be:

• Bright orange with many black spots

• Black with two large red spots

• Brown or almost fully black

• Completely unspotted

The individual I found indoors (see photo below) is one of the darker melanic forms. These darker morphs are common in overwintering clusters.

Are They Harmful?

Not to humans, but they can:

• Outcompete native UK ladybirds

• Release a yellow defensive fluid if squashed (it can stain)

• Occasionally bite, though harmlessly

Outdoors, they play a role in controlling aphids but indoors, they simply want a safe, warm place to sleep for the winter.

What To Do If You Find Them

A lone insect emerges on a bathroom surface, a straggler from a colorful hibernating infestation hidden behind the curtains.

A gentle approach works best:

• Use a glass and card to move them outside

• Shake or relocate curtains outdoors

• Let them settle naturally in sheds, bark, or cool crevices

They’ll quickly find another hibernation spot.

A Small Reminder From Nature

Encounters like this remind us how closely our homes are intertwined with the natural world. As we continue campaigning to protect wildlife in Dumbleton including our precious 11 bat species even tiny winter visitors like these illustrate how vulnerable beings seek shelter as their habitats shrink.