Ladybirds & firebugs — SOS 4D Paris

Asian ladybirds (Harmonia axyridis) gather in large numbers at the first cold snap. Drawn to sunlit facades, they accumulate on south-facing walls, around windows, under roof overhangs, in roller shutters, attics or lofts looking for a place to overwinter.

Indoors, it is not unusual to see dozens or even hundreds of individuals, mainly near openings or heat sources. When disturbed, they release a yellowish, unpleasant-smelling fluid that can leave lasting stains on walls, curtains, furniture and coverings.

Firebugs (Pyrrhocoris apterus) are easily recognised by their bright red and black colour. They live in very large colonies at the foot of trees, along low walls, terraces, garden borders or against sun-exposed facades. Although they rarely enter homes, their high concentration can become particularly unsightly.

The Asian ladybird is an invasive species accidentally introduced into Europe. Highly competitive, it threatens local ladybird species and can cause significant nuisance in homes.

An infestation may lead to:

• staining caused by the defensive fluid they secrete;
• marks that are difficult to remove from walls, curtains and textiles;
• allergic reactions in some people (skin irritation, rhinitis, asthma attacks);
• a massive presence that is especially disruptive in living areas.

Firebugs, on the other hand, are virtually harmless to humans. They do not bite, do not transmit diseases and do not damage buildings. However, when they gather in the hundreds or thousands, they represent a significant visual nuisance and can invade terraces, balconies, facades or house entrances. Their presence often reveals favourable settling areas that are best treated before winter to prevent proliferation.