I’ve had a few people around the office complain about ‘giant spiders’ this week. They’ve seemingly come out of nowhere and have set up shop in our homes, finding the sweet spot on our ceilings or hiding away in nooks and crannies, ready to dash across the room and scare the life out of us.
Personally, spiders terrify me – they have since I was a child. My mum once tried to catch one on the ceiling but ended up knocking it on to the bed in front of me, after which it proceeded to crawl towards me. It was the stuff of nightmares, and now I panic whenever I spot a mark on the ceiling.
But while they scare me, I know spiders serve a purpose, so I would never want to hurt one. I just want to find out why they’re coming indoors in the first place and how best to move them on. So I spoke to an ecologist and entomologist, aka an insect expert, to find out what we can do.
Why are there so many spiders right now?
‘Early September is peak time for people to notice large house spiders, but it isn’t necessarily because there are suddenly more spiders or because our homes contain something particularly attractive to them,’ says Adam Hart, professor of conservation ecology at the University of Gloucestershire and a Fellow of the Royal Entomological Society.
‘Many house spiders live in and around buildings throughout the year and remain relatively inconspicuous. At this time of year, mature males become much more active as they wander in search of females. That’s when people suddenly start seeing those very large, long-legged spiders running across floors, particularly in the evening.’
So we’re not necessarily dealing with more spiders here (at least not until the eggs hatch) – it’s just the spiders we already have are more active. Any you see scurrying around right now are more likely males that have decided to step out into the open in search of a female.
Adam surmises: ‘In many cases they’re not really being “lured” into the house at all. Some are already living there, while others can enter through open windows, doors and gaps as they move around.’ In short, the high activity makes them more likely to accidentally wander into your home through any entrances they stumble upon.
3 spider hotspots in your home
While spiders aren’t necessarily being lured into your home, there are things that make it a better habitat for them, says Adam.
Anywhere flies frequent
‘Food is perhaps the big one. A house with plenty of flies and other small insects obviously provides more feeding opportunities, particularly for spiders that build webs and remain in one place.’
So, consider where flies appear around your home – that tells you where you’ll find the spiders. Kitchens are the obvious hotspot, with crumbs and spills galore to attract rogue flies, as is the area around your bins, whether indoors or outside, which can be infested with maggots in the heat of summer.
But considering spiders will make a meal of flies, mosquitoes, clothes moths and even silverfish, they can technically be drawn to any room of the home.
Anywhere that’s dark and undisturbed
Adam continues: ‘Quiet, undisturbed areas such as garages, sheds, lofts, cellars and cluttered corners can also provide good shelter and places to build webs or hide.’
So, if your home is cluttered, you’re making it more accommodating for these eight-legged guests as you’re essentially giving them more places to stay out of sight from potential predators. While spiders are generally more active at this time of year, this could be where the they've been staying in the interim. A declutter method could help if that’s the case.
Spiders generally prefer quiet and undisturbed environment, so that makes your lesser-used rooms a bigger target, e.g. the garage, the basement or even the guest room.
Anywhere there’s other spiders
Of course, male spiders are on the lookout for female spiders, too – it’s their breeding season after all.
‘At this time of year, female spiders are probably the most interesting attraction of all,’ says Adam. ‘The large house spiders we see running around in autumn are very often males searching for mates. Male house spiders can detect chemical cues associated with females, particularly from silk, so if a female is established somewhere in a house, a wandering male can potentially detect her presence and seek her out.’
So all of the above will attract an initial set of spiders, which in itself attracts more spiders during the mating season.
How to get rid of spiders
There are lots of spider repellents you can buy that use essential oils, and there’s the old wives’ tale of using conkers to put them off your home. But, Adam says these aren’t all they’re cracked up to be:
‘I’d be very sceptical about most of the traditional remedies. Conkers, peppermint oil, citrus, various essential oils and ultrasonic devices are frequently suggested as ways of keeping spiders away, but there isn’t convincing evidence that scattering or spraying these around a house provides reliable protection.’
In fact, back in 2010, a group of school children proved that conkers have no effect on spiders and were awarded a prize by the Royal Society of Chemistry for it.
‘If you really want fewer spiders indoors, physical exclusion is much more sensible,’ recommends Adam. ‘Fit insect screens if you regularly have windows open, seal obvious gaps around doors, windows and pipes, and use draught excluders where appropriate.’
If you do need to catch and remove a spider, the tried and tested technique of trapping it under a cup and sliding a card beneath to carefully move it outside is still recommended – although spider-catching tools are also widely available if you’d rather not get so close.
Adam adds: ‘I’d avoid putting a spider straight outside into an exposed location simply on the assumption that outdoors is where it “belongs”. A shed, garage or other sheltered spot can be a better option for a house spider.
‘It’s worth remembering, though, that spiders are beneficial animals. A spider sitting quietly in a corner is providing free pest control by catching flies and other insects. If it isn’t bothering you, the easiest and most environmentally friendly option is often simply to leave it alone.’
So it’s best to avoid insecticides or swatters when it comes to spiders. They have their place in the ecosystem and can help to limit pests around the home. Bear in mind that once the mating season ends in November, they’ll be much less active – so less liable to make you jump as they dash across the floor!
