Honey, get a shoe...again.

May 26, 2012 8:21 PM

Solve for X, where X = number of spider appearances necessary to justify calling an exterminator.

We've been finding a few spiders from time to time in our house since moving in nine months ago, but now that the weather's warm we've found at least one spider a day for the last week.

They've shown up in many parts of the house, but primarily downstairs (the lower level of a split-level house). They are small dark spiders about the size of a nickel.

Neither my SO nor I are fond of spiders, but on the other hand it's not like they're pouring out of the walls Forbidden Forest-style. But as it has come to be a couple spiders a day, and as we have a baby on the verge of learning to crawl, is it worth ponying up the dough for an exterminator? Or is there something else we could do first?

posted by daisystomper to Home & Garden (20 answers total)

Spiders are generally good, they kill other insects. Unless these are some sort of Australian poisonous spiders I wouldn't call an exterminator for less than ravening hordes.
posted by Justinian at 8:23 PM on May 26, 2012 [5 favorites]

A crawling baby is a far bigger threat to spiders than vice versa, just ask my daughter. I live in the woods, and there is no shortage of things that live out here and would like to come inside. We probably see a spider somewhere in the house nearly every day and haven't worried about it. It's not as if the house is infested, and if you killed all the spiders currently inside, more would wander in.

What could you expect an exterminator to do? If they tent your house then you have to move out for a couple days, and if there's not some sort of spider breeding den in the house, then no underlying problem will be solved, you'll just get new spiders wandering in from wherever they come from, and you'll have saturated your house with poisons that are almost certainly more dangerous than whatever sort of spider you're finding in your house. Does it end up being worth the cost?

They're just spiders. If they're not black widows or something it's probably not a big deal.
posted by tylerkaraszewski at 8:35 PM on May 26, 2012 [1 favorite]

If you send us a picture of a typical spider in your house we might be able to reassure of its harmlessness, if that would help.
posted by Scientist at 8:36 PM on May 26, 2012

I would put X somewhere between 8 & 12 a day. But it really depends on the spider. I use to live in an apartment on a hillside on the edge of a forest. I had jalousie windows so I got lots of spiders. Some I would escort back outside. Others would get squished. But this time of year, probably 3-5 a day would get in. It's where I got over most of my heebies about spiders. Now, when I lived in England, we'd get the occasional Huntsman spider (I think that was the name). They are fairly harmless to people but very large and fast. If I was getting 1 of those a day, I'd call somebody!

Mostly spiders don't bite and they are mostly helpful.
posted by amanda at 8:44 PM on May 26, 2012 [1 favorite]

X=8/day.

I'm scared of spiders, but I'm more likely to avoid exterminators/pesticides with a crawling baby!
posted by palliser at 8:59 PM on May 26, 2012 [1 favorite]

Oh, man. For me, X= a number between 1 and 2. But I hate spiders.
posted by woodvine at 9:15 PM on May 26, 2012 [2 favorites]

I would never consider a lot of spiders to be a problem. Spiders help to keep you from being overrun by the types of creatures that feed on your blood or shit in your food.
posted by bonobothegreat at 9:20 PM on May 26, 2012 [1 favorite]

You can do this search: "poisonous spiders" + name of your state. Or "common spiders"+name of state. Your state's extension service has probably put up a handy page with photos of the spiders that are worth worrying about, such as black widows, so you can learn what they look like.

Probably the spiders you're seeing are harmless and are helping you to reduce the population of insects in your house.
posted by LobsterMitten at 9:21 PM on May 26, 2012

For balance in this situation, research the long-term effects of the chemicals that exterminators would use. The set of spiders worth expending serious chemicals to exterminate is very small.
posted by dws at 9:31 PM on May 26, 2012

The spiders are exterminators. And they never send a bill.
posted by tyllwin at 10:05 PM on May 26, 2012 [10 favorites]

Best answer: I would never call an exterminator for spiders (assuming they aren't black widows)-they are too useful for controlling other insects. However, multiple daily sightings of different spiders would start making me really curious about what was drawing them in the house. An infestation of something the spiders couldn't control would send me to the exterminators. I would clean the house thoroughly, especially along the baseboards, and make sure screens fit and obvious entry points are closed. If you still can't find an obvious reason for the spiders, then they are doing their job and I would just leave them alone.
posted by dness2 at 10:16 PM on May 26, 2012 [1 favorite]

If you live in the northern hemisphere the spiders you're seeing have been living and will continue to live in your house for a long time. The reason you're seeing so many at this time of year is that this is when they tend to come out to mate, especially if you're living in a more southern (read: warmer) climate. If you can capture one or take a clear, non-blurry picture of one you could get a hold of your local college extension office at this lovely link here and ask them.
posted by ZaneJ. at 11:36 PM on May 26, 2012

What dness2 said. It's very likely you're seeing spiders because you have spider food in your house, i.e. insects -- generally smaller and more numerous. Because these aren't predators, you won't see them out and about as much, but they're there or the spiders wouldn't be. In turn, the insects will be feeding on fungi and other things.

Is your basement damp? Perhaps a dehumidifier is what you need most. Look for places where spider webs may indicate the presence of insects. Look for gaps to the outside that you can caulk. Sweep surfaces clean. Look for plumbing or roof leaks that can contribute to dampness. A clean, dry basement will harbor in time fewer and fewer things that lead to bugs and spiders.
posted by dhartung at 1:57 AM on May 27, 2012

I have a quarterly exterminator "for" spiders but it doesn't actually "kill" spiders. Instead, the idea is that the pesticide keeps insects from coming in, and therefore keeps spiders from wanting to come in.

The treatment I get is outside along the house foundation only, no spray indoors. The spray along the foundation is like a line... bugs live fine outside but won't cross it to get in. Insects and spiders continue to live outside, plentifully, where they belong. We still get the occasional spider and/or insect inside, but it has been a huge improvement.

A couple of spiders a day was enough to get me to do this, but you have to go with your own comfort level. Your house should be a place that you are comfortable in, and if you're not comfortable with that many--despite the fact that many of the above posters are--then it's worth doing something about.
posted by dayintoday at 4:11 AM on May 27, 2012

IANAE, but my exterminator says that pesticides authorized for home use are not effective against spiders or scorpions. When they spray, they are spraying to kill the prey that spiders and scorpions eat, and they leave when the food is gone.

We have chosen to do the outside treatment around the warehouse. The exterminator sprays about a six foot swath all the way around the building, and refreshes it about every other month. We haven't had any termite swarms or ant problems for about a year (a miracle in South Florida), and we're down to about one spider/scorpion per month, so I guess it works pretty well.
posted by halfbuckaroo at 4:54 AM on May 27, 2012 [1 favorite]

Do you have any largish plants inside? Plants provide a nice "natural" place for spiders to hang out and quietly do their thing without having to crawl across walls and ceilings. If you get a few leafy plants, you'll probably see a decrease in the number of spider sightings.
posted by RonButNotStupid at 6:20 AM on May 27, 2012

I'm not a fan of spiders either, but spiders are better than almost any other household pest.
posted by two lights above the sea at 6:49 AM on May 27, 2012

If they are a type of spider you do not want, glue traps are efficient. We use them for our brown recluse problem. You may see only one a day, but under your bed sees more. Finding a forgotten glue trap is like a horror movie.
posted by oomny at 8:25 AM on May 27, 2012

Some spiders that are not particularly dangerous bite and those bites are nasty. I know, because they've been biting me. The bites are about the size of mosquito bites except they are harder/denser and they last a lot longer. One of my neighbors, an otherwise healthy woman in her thirties, had bites that got infected and she ended up spending several days in the hospital.

If there is any indication that your spiders bite people do whatever you can to get rid of them. I've heard the same thing from exterminators, they don't have anti-spider capabilities. I'm vacuuming a lot and I'm definitely going to try the glue traps.
posted by mareli at 9:01 AM on May 27, 2012

One more thing, I've heard that sprinkling salt around baseboards works.
posted by mareli at 9:02 AM on May 27, 2012