If your home has become a fly-filled nightmare this summer, there could be a surprisingly simple solution – and you don’t need a swatter or spray.An insect expert has revealed how to catch the pesky invaders with your bare hands, using a simple trick that exploits the way flies react to movement.The key, she says, is to approach slowly from above – because when flies sense danger, their instinct is almost always to shoot upwards.Dr Jessica Stokes, Project Officer and Fellow of the Royal Entomological Society, said: ‘Most house flies have very good eyesight, particularly when it comes to movement. The advice is therefore to approach them slowly, ideally from above.‘Flies will almost always fly upwards, which is why many traps are designed a little like a lobster pot hanging vertically.’To catch a fly with your hands, it’s best to aim a few inches above the fly’s resting position rather than the surface where it sits.Flies can detect rapid changes in air pressure and movement and, when threatened, instinctively launch themselves upward to take off.By targeting the empty space above the fly, it will fly straight into your closing hands – where you can keep a hold of it until releasing it outside. An insect expert has revealed how to catch the pesky invaders with your bare hands, using a simple trick that exploits the way flies react to movement Dr Stokes said Britain’s warm, humid spell may have sparked the feeling that homes are being invaded by a ‘fly epidemic’.Higher temperatures accelerate insects’ development, meaning many species can complete their life cycles faster and become noticeable in greater numbers, she explained.With Brits throwing open windows and doors to cool their homes, flies have even more opportunities to get inside.Fruit flies are particularly fond of warm, humid conditions and can quickly home in on fruit bowls, sinks, drains and compost caddies.But while they may be an unwelcome sight in the kitchen, flies play an important role outdoors as pollinators and decomposers, breaking down organic waste and recycling nutrients into the soil.Rather than simply killing them, it is best to capture them and release them outside your home, the experts said.‘Insects often get a bad reputation, but the reality is much more interesting,’ Dr Stokes said. ‘Insects are quietly doing some of nature's most important jobs.‘Our aim is to help people understand them a little better and find simple ways to keep them out of our homes while allowing them to thrive outdoors, where they pollinate plants, break down organic matter and provide food for countless other species.’For those wanting to deter flies from their homes she recommends using citrus peel, which emits a scent insects find overwhelming.She also said peppermint oil can overwhelm insects’ sense of smell and mask the trails and food odours they rely on.‘Use a few drops in water in a spray bottle around doorframes and windowsills, or cotton balls soaked in neat oil left in problem spots,’ she said.‘This will need topping up every few days as the scent fades.’Dr Erica McAlister, Principal Curator for Diptera and Siphonaptera at the Natural History Museum and Honorary Fellow of the Royal Entomological Society, explained that flies could also be entering your home to escape the summer’s intense heat.She suggests putting up screens – made of beads or something similar – to prevent flies entering in the first place.‘I am a shooer,’ she said. ‘I coerce them outside by waving – but I understand if there are a lot this may be problematic.‘So you could catch them in pots by moving very, very slowly.’