Why your house is teeming with ladybirds: Horrified Brits say their homes are crawling with insects - here's what's behind the invasion

If you've spotted swarms of ladybirds clinging to your windows or crawling across your walls in recent days, you're not alone.Homeowners across the UK have reported seeing unusually large numbers of the insects gathering on houses as autumn temperatures begin to fall.According to experts, many of the insects turning up in homes are harlequin ladybirds, an invasive species that has become widespread across Britain since arriving in 2004.They are noticeably bigger than native ladybirds and may bite if handled, leaving a red mark.As the weather cools, the insects begin searching for sheltered spots where they can spend the winter in a dormant state.That often brings them into close contact with people, as houses provide the warmth and protection they are seeking.John Whiteley-Wilkson, managing director of Acorn Environment Services, said: 'People are often surprised by how many ladybirds appear all at once, but they're simply looking for a safe, dry place to spend the winter.'Homes provide ideal shelter as the weather starts to cool.'Horrified Brits have shared videos of ladybirds clinging to doorframes and windows. Homeowners are seeing unusually large numbers of the insects gathering as temperatures begin to fallOne reason the influx can appear so dramatic is that ladybirds rarely hibernate alone.Instead, they often gather together in large groups, meaning dozens can suddenly appear on the same wall, window frame or doorway.'It's completely normal for ladybirds to gather together before hibernation,' Mr Whiteley-Wilkson said.'While it can look like an infestation, it's usually just a seasonal behaviour rather than a sign of a pest problem.'Many homeowners first notice the insects on south-facing walls, which absorb more heat from the sun during the day.The extra warmth helps the ladybirds conserve energy before winter fully takes hold.'You'll often notice ladybirds gathering on the warmest side of a property,' the expert explained. 'They're making the most of any remaining warmth before temperatures drop further.' According to experts, many of the insects turning up in homes are harlequin ladybirds (pictured), an invasive species that has become widespread across Britain since arriving in 2004The Natural History Museum says harlequin ladybirds are particularly well known for entering buildings in autumn and can sometimes congregate in large numbers.'Harlequin ladybirds are pretty distinctive, even though they have lots of colour forms,' Max Barclay, senior curator of beetles, said.'You can find different varieties, from red with black spots, to orange ones and even black ones with red spots.'Experts say the easiest way to identify a harlequin ladybird is to turn it over. Unlike native species, which typically have black undersides and legs, most harlequins are orange underneath with orange legs.Harlequins are also known for carrying a sexually transmitted disease, called laboulbenia, which is a fungal infection that forms scales on the wings of ladybirds.Thankfully, it cannot infect humans.'It's a fungus that grows on the exoskeleton and we don't have one of those,' Mr Barclay said. 'Also, we don't have sex with ladybirds.' As the weather cools, the insects begin searching for sheltered spots where they can spend the winter in a dormant state (stock image)The easiest way for ladybirds to get into your home is through small gaps along the edges of loose-fitting windows.And while it's common to find them in your home, experts urge people not to kill them.'These ladybirds don't want to be in your home any more than you want them there,' Mr Barclay said.'If people squash them, they can stain walls with their defensive yellow chemical secretions which can be slightly smelly.'To get rid of the insects, the best thing you can do is to 'help them find a way out', Mr Barclay explained, adding: 'The ladybirds will be grateful and may even repay the favour by eating some of the greenflies on your roses.'For those keen to keep the insects outdoors, experts recommend sealing small gaps around doors, windows and air vents.'Ladybirds aren't trying to invade your home – they're simply looking for somewhere protected to spend the winter,' Mr Whiteley-Wilkson concluded.'Preventing them from getting inside is usually just a case of sealing the small gaps they use to enter.'