Why You Shouldn't Squish That Spider, Even If It Gives You The Creeps

Jun 1, 2018
Originally published on May 31, 2018 4:41 pm

People aren’t usually overjoyed to see a spider crawling around inside their home.

But Matt Bertone, an entomologist at North Carolina State University, says spiders are an important part of our indoor ecosystem and rarely a danger to humans — so it’s best to just leave them alone.

“They’re part of our environment. I don’t think we can completely sterilize our home environment,” Bertone (@Bertonemyia) tells Here & Now‘s Jeremy Hobson. “I also think that they’re not doing anything bad. They are interesting to observe. And it’s interesting to know that there are other organisms that find our houses nice, and I think they get a bad rap in general.”

How Do Spiders Find Their Way Inside?

“Spiders are really active,” Bertone says. “A lot of them are hunting on the ground outdoors. And your house, no matter how tightly sealed you think it is, has cracks and crevices and they may come in, get stuck inside. And that’s when you usually find the dead spiders, the ones that can’t survive for long periods of time in the house. So those types, it might be beneficial just to release them back outside.”

Where Are They Typically Hiding?

“Many different places. In the corners, under things, they don’t like to be out in the open necessarily unless they’re away from activity,” Bertone says. “So you’ll find them under cabinets, but also in places that you expect more wildlife to be, say in basements or in workshops, places where there’s more humidity, things like that.”

If You See One …

“For me, I kind of just let them be and kind of crawl around and go their way,” Bertone says. “If you’re really not interested in them being in your house, it could be that you catch it and release it outside. Some of them are inside accidentally so it might actually help them.”

Yes, Spiders Can Actually Help You

“Outside, they’ll catch bees and things that we tend to like,” Bertone says. “But they will also happen to catch pests, and if you do have an infestation at home, they will catch a lot of those pests. You can see spiderwebs out in your lights that have tons of midges or mosquitoes in them.

“And of course also some spiders often feed on other spiders. For instance, spitting spiders are known to feed on a lot of other spiders, including brown recluses. So identification of the proper spider, too, may help, because you may kill a spider that was there benefiting you.”

What About Bites?

“That’s a common fear, and I will tell you that spider bites are extremely rare,” Bertone says. “A lot of people wake up in the morning, and they have some kind of red bump on them, and they assume some spider bit them at night.

“But in many of the cases — where spiders do bite and the ones that can actually pierce your skin, are big enough to actually deliver a bite — you have a crushed spider that you pinched up against, you leaned up against the wall, you stuck your hand in somewhere where a spider was resting, and those are the cases that are true bites.

“Spiders are really not interested in biting you while you sleep, or even probably being near you when you sleep.”

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