French homes overrun by ladybird invasion

France is facing an overwhelming influx of ladybirds this autumn, particularly from the invasive Asian ladybird (Harmonia axyridis).

This phenomenon has been widely reported across various departments, including Haute-Saône, where residents have observed these insects invading their living spaces. 

While ladybirds are generally harmless, their sudden presence in homes can cause concern. 

They can emit a foul-smelling yellow fluid when threatened, which may stain surfaces. 

Additionally, some individuals may experience allergic reactions to the insects.

You can spot the difference between an Asian ladybird and domestic European ladybird by counting the number of spots on the back of the insect. 

If it has more or less than 7 spots, it is not European and is likely an Asian ladybird.

Warmer summer leads to more food for ladybirds

The surge this year is attributed to several factors, including warmer-than-average temperatures experienced during the summer and autumn months. 

This has led to an increase in aphid populations, a food source for ladybirds, contributing to their proliferation. 

The ladybirds are also seeking shelter for hibernation, often choosing to enter homes and buildings, especially those with white exteriors that reflect sunlight and offer warmth.

The Office Pour les Insectes et leur Environnement (OPIE), a French NGO dedicated to the study and protection of insects, has highlighted the ecological impact of the Asian ladybird. 

They note that it was introduced to Europe in the 1980s for biological pest control but has since become invasive, outcompeting native ladybird species and potentially spreading diseases among them.

Several other insects originally from Asia are now invasive species in France, including the Asian Hornet and Japanese Beetles. 

François Lasserre, Vice-President, OPIE, emphasised the multifaceted nature of the migration patterns observed in Asian ladybirds. 

He noted that while climatic factors play a role, the availability of food sources such as aphids and the absence of natural predators contribute to the population boom. 

Mr Lasserre suggested that the influx into homes is a seasonal behavior, with the insects seeking hibernation spots as temperatures drop.

 “Such invasions are temporary, as ladybirds typically hibernate during the autumn months,” he said.

Asian ladybirds have also been frequently spotted in the UK this summer, as population numbers increase there too.

France’s National Research Agency (ANR) is also conducting genomic studies to understand any evolutionary adaptations that have enabled the success of Harmonia axyridis in Europe. 

Ladybirds unlikely to cause issues

While some find the influx concerning, others view it as a natural occurrence. 

Despite higher than average numbers this autumn, there is little reported threat to France’s ecosystem.

To reduce the risk of ladybirds entering your home, experts recommend sealing entry points such as cracks and gaps around windows and doors.

If any stray ladybirds do make it inside, gently remove them by capturing them in a container and releasing them outside.

If you use ladybirds in your garden as a natural pest control, it is recommended to favour domestic European species.