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Are There Brown Recluse Spiders in Your House?
Brown recluse spiders (genus Loxoscleles) are fairly large, dark-colored spiders that live in corners and neglected spaces inside your home or garage. They come out at night to hunt for small insects and other spiders, and for this reason spiders in this group are sometimes called "wandering spiders." Some spiders in this group are among the most venomous arachnids in the world. The brown recluse bite causes little pain at first, but over time can cause a growing would as the toxin kills flesh. Brown recluse bite symptoms can be quite ghastly, with an ever-widening lesion that can develop over weeks and require surgery to repair.
How to Kill Brown Recluse Spiders in Your House
Sticky traps are a very simple method of pest control. They're nothing more than a sticky surface that immobilizes and kills wandering spiders. These are "passive" traps that you don't need to set or attend to -- just check them once in a while, and when they're full of insects, simply throw them away.
The main drawback is that these traps will catch and kill beneficial insects as well as harmful ones. Centipedes and other basement arthropods are sure to wander into the trap, so it isn't wise to just put them out if you don't know you have a brown recluse problem.
Brown Recluse Spider Sticky Traps
Spiders in a Sticky Trap
How to Identify Brown Recluse Spiders
You can identify brown recluse spiders by the violin shape on their back -- it's a reliable marking that even non-specialists can see. This marking may be faint or different in very young or immature brown recluse spiders. In adults, the combination of long thin legs, a pale brown body, and a darker violin mark on the back will serve to identify a brown recluse.
If you have a spider you do think is a brown recluse, carefully coax it into a jar or bottle and bring it to the nearest doctor's office. They will be able to tell you if it is indeed a brown recluse. If it is, you need to work to get rid of brown recluse spiders in your basement, house, or garage.
Weird Facts About Spider Webs
Most spiders spin a web with which they snare their prey. The "silk" that they use is actually a liquid that hardens when it comes into contact with the air. The spiders store this "web liquid" in their body until they need it to spin a web.
Since it takes a lot of energy and a lot of raw material to produce this substance, spiders regularly recycle it. This means that after they have had a web out for awhile, and it has become tattered or isn't producing enough prey, they literally eat the entire web and convert it back into web liquid. Then they move to a better spot and use the same material to spin a new web. If you are a student of spiders, or just like satching them do their thing, you will eventually witness a spider eating its own web.
Spiders typically produce different kinds of webbing for different jobs. For example, they use smooth, non-sticky webbing for places where they need to maneuver, and sticky areas for the parts that need to catch and hold the insects that are unfortunate enough to fall into the web.
Garden spiders are known to include a "warning stripe" in their webs to keep birds from flying through it and destroying it.
Brown Recluse Distribution in the U.S.
Brown Recluse Hunting Habits
Brown recluse spiders do spin webs, but they are typically disorganized and not intended to snare prey. Instead, these and other "wandering spiders" catch prey by roaming around and looking for it. When they find a suitable target, they quickly catch, bite, and subdue the unfortunate insect.
Brown recluse spiders eat centipedes, cockroaches, silverfish, and other spiders, among other things. Overall, they are beneficial to the homeowner, since they help control some pretty nasty bugs. Unfortunately, their bite makes them a little too risky to have around, especially if there are a lot of them, or you have small children playing in the same area where the brown recluse spiders are living.
Brown Recluse Fangs
All spiders, including the brown recluse, are predators. They use sticky webs to snare prey, mostly insects, and they all have fangs. The fangs of the brown recluse, like other spiders, are sharp, hollow tubes that inject toxins into the prey to dissolve tissue and internal structures into a kind of soup. Once the prey has been liquified, the spider uses its fangs as straws to suck up the broth.
The Bite of the Brown Recluse
When a brown recluse bites, it releases a toxin that liquifies the cells of the prey. They then "drink" the liquified insides through their hollow fangs. This same toxin also destroys the tissue of humans, and some brown recluse bites can turn into slowly growing lesions that may ultimately be several inches across and consume both skin and muscle. Bites like these are seldom life-threatening, but the damage they cause can be very painful and disturbing, and can ultimately require reconstructive surgery.
Not all brown recluse bites turn into such a gruesome wound. As a matter of fact, some believe that the toxin itself is not what causes the worst damage -- instead, they suggest, it's the result of secondary infections that follow the original bite lesion.
Is It a Brown Recluse?
Have a look at THIS GUIDE for a detailed look at the brown recluse spider.
Before You Set Out Traps, Make Sure You Actually Have a Brown Recluse Infestation!
Your basement is host to a number of harmless and helpful insects, spiders, and other arthropods. Centipedes, especially, are your friend, because not only do they eat dead debris and other gunk, they also consume cockroach eggs. Pretty gross, but also pretty helpful.
The following sources were used for this article:
(all images public domain)