Keeping spiders in the house as pest control?

[Cavedweller]

I've wanted to do something like this for a long time, and the plague of fungus gnats I'm currently experiencing has finally driven me to action.

Does anyone keep wild spiders in their house/kitchen as pest control? What would be the best way to encourage a spider to set up shop in your house? Should I just go outside and catch some? What kind of spider would be best suited to this role?

 

[Curious jay]

I have some sheet web/ money spiders (unsure of scientific name because they're so small I can barely get a decent visual of them lol) that I place around my more humid enclosures they seem to keep the fungus knats down.

I would say Steatoda but fungus knats are so small they will probably wriggle through their web layout before they can get to them.

Alot of baby orb weavers around this time of year could set them in an area where they can feed on them until they get larger, if they have a good food source they won't move their webs.

I'm sure someone will have some better suggestions for you.

 

[The Snark]

I fostered pholcids for years but the mess they made in comparison to the few bugs they actually caught wasn't worth it. We let the sparassids have the run of the house, partly for pest control and partly as a safer area in the lethal ongoing game of tag outside, and of course the jumpers and the Lycosids are always welcome.

 

[Gnat]

I have massive amounts of Kukulcania hibernalis living in and around my house along with a few species of cellar spider and false widows. I have a massive explosion of gnats in my house too and the spiders seem to do nothing to impact the problem. They have never really been all that great at general pest control but are neat to have free ranging in the house. There are a few 'wild' K. hibernalis that I feed occasionally.

 

[Ciphor]

First, you already have a ton of spiders in your home, you just don't see them, and they don't prey on Gnats. If your looking for something that is effective at catching Gnats you need a very specific type of spider.

1) Linyphiidae - Linyphiinae. Both sub-families are good at Gnat catching, but honestly the larger sheet web spiders in Linyphiinae would be the best, they literally specialize in catching things like Gnats. http://bugguide.net/node/view/1973 They are available in the wild all year round, different species at different times. The tough part is transporting them safely, they are very fragile spiders and off a web they do not live long. Best method is to capture them into a vial with some tissue so they cannot move around. Gently place them around the spot where the Gnats are. Some will take foothold, some will leave, some will die to other house spiders as they explore for a good spot. It is not easy to establish, I'll tell ya that right now.

2) Linyphiidae - Erigoninae. The other sub-family, also known as dwarf spiders & money spiders. The thing about these guys is, they are freaking small and make small webs. They are likely already in your home, and in spots you never think to check, or you see their tiny webs but never see the spider. Really, I'd just leave this one alone, it would be impossible to get enough of them to control and Gnat problem, however good at catching Gnats they are.

3) The last Option, and maybe the most viable for you, Orb weavers. Juvenile orb weavers will work exceedingly well, and they absolutely will post up a web where Gnats are buzzing even if it is indoors! There are some smaller species of orb weaver that work very well, but I'm not sure what your fauna looks like. If you can find a river with lots of trees around it, you should be able to find some Metellina spp. Really, any orb weavers in the family Tetragnathidae would be great as they all eat small flyers like Gnats. You will recognize it is a Tetragnathid by the orientation of the web. Tetragnathids make horizontal orb weavers while Araneids make vertical orb webs.

 

[Cavedweller]

Thanks guys! I live on a top floor apartment now, and I haven't seen nearly as many bugs in the house as when I lived on the ground floor. Ciphor, I'll try to look into the types you recommended. I have the worst luck with trying to find wild bugs, even though I live on a greenbelt. There are creeks in the greenbelt, maybe I can find some spiders there.

Worst case scenario, I guess I'll try to get some kind of butterwort? I hear those are great for gnat control.

The local LPS has a ton of wild spiders around their tarantula enclosures, those might actually be for gnat control now that I think about it. I wonder if I can buy some from them.

 

[The Snark]

We have some species of mites which make a nearly invisible webbing very close to wall or ceiling surfaces. They have literally coated the entire ceiling of our carport. Leaving the light on at night out there, well, I'll guesstimate that ceiling kills about a few billion gnats every year. The mites may not even eat them, just create a formidable death trap.
Here's a pic. The webbing itself is invisible. The little dots are gnats, along with some termite wings. The webs keep loading up with prey until it droops down in sheets. A minute or two cleans the whole ceiling and the cycle starts over.

 

[Smokehound714]

the ONLY way to effectively control fungus gnats is to dry their habitat out, which is, unfortunately, impossible with certain species.

They thrive in clogged pipes, wet substrate, and decomposing matter.

The larvae are actually beneficial to moist enclosures, as they are a clean-up crew, and keep mold down, however they're annoying little buggers!

To prevent them from escaping and overrunning your home, try stretching a section of knee-high nylons over the top of your enclosure. This excludes most pests AND provides fantastic ventilation!

These are very useful if you're breeding true spiders that can scale smooth surfaces, providing excellent ventilation while preventing the tiny slings from escaping from normal ventilation holes.

Here are a couple of pics to show, if you get any small holes in the nylon, simply roll up a wad of paper towel, and jam it into the hole, and the problem is fixed

because of nylon's stretching ability, one size virtually fits all but the largest lids. It may not be as pretty as a plexiglass lid with fancy metal screen holes, but it's very effective. give it a try!

 

[marclar]

Pholcids and Tegeneria do the job for me

 

[Ciphor]

Pholcids and Tegeneria do the job for me

Your tegens eat Gnats?

 

[marclar]

Your tegens eat Gnats?

I'm not sure if they eat them, but there is a ton of teg's in my back garden and garage and their webs are full of gnats

 

[dzinger14upc]

Never heard of that!

LOL! I'm a pest control specialist and I've NEVER heard of that idea! Just let them loose and do their own thang! Thats what I propose! LOL but i'm sure management won't allow that :-/

 

[Ciphor]

LOL! I'm a pest control specialist and I've NEVER heard of that idea! Just let them loose and do their own thang! Thats what I propose! LOL but i'm sure management won't allow that :-/

That is because pest control specialist are usually fire salesman who prey on ignorant peoples fears of venomous spiders. You sell very expensive chemical spray jobs that hurt the home owners more then help.

Obviously not all pest control experts. Bed bugs are a real issue and bees can be as well, but any pest controller who comes out to respond to spider infestations is usually selling fire. "Oh that? Oh no, those are brown widow recluses, hybrids that cause your spine to rot off, let me grab the expensive stuff, can't put a price on your safety!!"

 

[The Snark]

ROTFL. I think you meant brown black wandering reclusive funnel web banana widow, yes?

 

[Formerphobe]

I don't 'keep' them per se, neither do I discourage them from setting up shop. Unless I catch a orb web with my face, then they get relocated. My daughters, on the other hand = death to wild spiders that don't look like possible escapees of Mom's (all currently present and accounted for...). I currently have a couple of unspecified jumpers that moved into my bedroom. Large numbers of Dolomedes tenebrosus provide pest control in the basement and garage and I occasionally find them in the house proper. Lower numbers of Lycosidae (I think the D. tenebrosus keep them at bay). And we have Bathroom Spiders - Lord knows what species - ~1 inch dls, black with tan patch on dorsal abdomen, free range (no established web), not jumpers. Occasional Lactrodectus sightings in garage and on grounds. Then there are all the species that I never see.

 

[Heckboy]

I do tend to encourage garden orb weavers to set up shop on my deck as much as possible. False widows get brought to outdoor light fixtures to set up homes.
Best of both worlds, that way... the spiders set up webs, eat mosquitoes, and I have a bunch of awesome "pets" who get to exhibit their natural behaviors.
Tegenarias are a bit more challenging. The rest of my family wants to squash them on sight; technically, since they are considered an invasive introduced species around here they are in the right... but I like them so damn much! I just quietly find them new, safer hiding spots when I uncover them from time to time.
Now... if only we had native species large enough to eat the occasional rat. Granted, the cats do that (one does anyways... the other is a bit of an idiot), but I like spiders more.