Brown Recluse Natural Enemy

I am a 45 year old college student studying computer science. Two of my classes were biological study under the instruction of Irving Rushing. Mr. Rushing's "old school" teaching techniques included inspiring the students to perform science studies using the "scientific method". I became curious about the Brown Recluse (Loxosceles reclusa) spider. I had seen what I thought might be a Brown Recluse on several occasions at a friend's garage and decided to confirm that the garage was either infested or free from the dangerous spider. After performing some basic research to identify the spider it became evident that not only was the Brown Recluse present in the garage, but an opportunity to collect and study the spider in its habitat was too tempting to pass up. I do not have a degree studying spiders and concede that what I am doing can not technically be defined as a "scientific study", but, I am observing the Brown Recluse in its natural environment and some of the behaviors are somewhat different than laboratory observations. Unfortunately, my research is developing more questions than answers as you'll see. The main goal here is to STOP the hysteria and clearly separate fact from fear.

I hate to lose my readers but here is the condensed version of the Brown Recluse with links provided. Due to the Brown Recluse's region, misdiagnosis is common as some physicians quote while others rebut Internet pictures of bites and say they are uncommon since 2,055 spiders didn't bite a family and there are none in California because the identity was not verified. So that's what the rest of the world is working on and I hope you made it back here to see what everyone else isn't doing in the field.

This is the largest that a Brown Recluse can grow. It has been reported that they can live 5 to 10 years. Note the size in relation to the dime in the photo. Also note that the majority of Brown Recluse that are encountered will be half this size or smaller. Of the many that I have gathered, this one is by far the largest. It also appears to be the only male gathered so far. Male spiders have an enlarged bulb at the end of the pedipalp (what most people call antenna).

There is somewhat of a divided theory among physicians and researchers as to whether the Brown Recluse is widespread and or dangerous. The flesh eating properties of the spiders poison is actually blamed, by some researchers, not on the poison of the spider but the flesh eating bacteria discovered in the 1990's. The "bullseye" inflamed area can also be Lyme Disease. Some physicians adamantly claim that the bite causes the loss of tissue and have posted pictures of victims on the Internet to prove it.
The Brown Recluse is anything but a recluse. All of the specimens that I have found have been in very busy areas. It is true that they do prefer areas that are seldom disturbed, but this area can be a pair of gloves on a shelf, or a shirt in a closet. The fact is that these spiders do not only hide in a shed that isn't used but twice a year, but a pair of gloves that haven't been used for several days. The fact is that a Brown Recluse can usually be seen in plain sight when the lights are turned on and will run into hiding when their area is disturbed.
The first task is to determine if in fact an infestation is present. To identify the Brown Recluse, it's imperative to understand several unmistakable characteristics beginning at the head. The Brown Recluse, unlike most other 8 eyed spiders has 6 eyes. The eyes are in 3 pairs on the head. Next, the fiddle is present on top of the back and what would be the neck of the fiddle points toward the rear of the spider. The abdomen is connected to the back and usually a grayish color. The rest of the spider's color is a light brown other than the dark fiddle. The largest confusion comes from people who see markings on the abdomen. There are spiders with fiddle shapes on the abdomen, which are not Brown Recluse. So, the body structure in order is the head, the back, and the abdomen.
Often the spider is discovered in the "resting position". If a person finds a spider with the front 6 legs bent toward the rear of the spider (feet pointing forward) and the rear 2 legs bent toward the front of the spider (feet pointing to the rear), then this is possibly a Brown Recluse. The spider must also have the fiddle on its back to be a Brown Recluse. In the resting position, the legs will be laying almost completely flat.
The Brown Recluse do not have a distinctive web but do spin several single strands that will eventually total many single strands if the spider resides in the area for several months. I have seen the spider actually build a web, but, it occurred between boards where it was tending to an egg sac. A person should be wary if they come across such slight indications of "weblike structures". At any rate, if this is a Brown Recluse "weblike structure", the spider will be within inches of the formation and disturbing the structure will cause the spider to run out and make itself seen. These spiders are very fast. They usually run away but several have actually ran toward me seeking shelter in my gloves. It's very important to understand that disturbing these sites will result in a visible spider and an unsuspecting individual could have one of them up their sleeve in the blink of an eye. These spiders also build an egg sac, which is round to oblong and about 3/4 inches in diameter for the actual sac, but a "weblike" structure may also be attached measuring about 1 1/4".

I have found a Brown Recluse inside a membrane and on top of the egg sac once the offspring have hatched out. This situation not only verifies a single spider but at least 50 almost invisible offspring in the area. From experience, if a person happens across this situation while cleaning, let's hope an air hose is not involved. This was the point where I stopped using the air but not soon enough to discover a Brown Recluse adult crawling across my shoulder while driving home. The procedure in this situation is to calmly but quickly exit the road and get that jacket off fast. I'm not reporting what happened verbally. If the weather had been warmer, I wouldn't have had the luxury of noticing the spider in time. Keep in mind many species use the same egg sac style and it should not be assumed that the sac must be destroyed since many spiders are beneficial.
The breeding season has been reported in Texas as being in May or June. I gathered several Brown Recluse specimens on February 11, 2004 which consisted of 3 different development levels meaning that it is possible that the Brown Recluse breeds year-round in ideal conditions such as the 2003-2004 season where the temperature did not drop below 19 degrees for more than 24 hours. A specimen was also found in March with temperatures in the 30's although the specimen was lackadaisical and near a former egg sack. Specimens gathered on June 8, 2004 proved to have the same development pattern with 3 different sizes. This is when I observed that they are not slow but very fast. If you come across a slow moving spider in warm weather, it is not a Brown Recluse.
The Brown Recluse has been reported to be the only spider that exists as a community. This is true to some extent. A specimen captured on one day and placed in a jar was killed by another specimen caught 2 days later and placed in the same jar. These spiders were found in the same area and it is possible that a territorial squabble was brought to a head with the close proximity. A professional has reported to me that containing specimens like this can trigger "survival instincts". Another gathering of 3 different generations, which were placed in the same jar resulted in instant death for the smaller 2 of the 3. They may live together, but they stay away from each other. The 3 February specimens of different sizes existed in total peace for 2 weeks. It appears that the cooler weather calmed them enough to become acclimated with each other before the temperature was increased. The specimens were donated to Irving Rushing's science department and were, therefore; not monitored for cohabitation. The spider found in the June 8, 2004 gathering appears to designate 12 to 18 inches between adult spiders. An important finding at that time was the presence of a molted shell 3 to 6 inches away from the nest and the molted shell was always found on a vertical surface although later moltings were occasionally found on a flat surface. In general, they seem to prefer horizontal surfaces and I have witnessed moldings side by side as they matured through 3 generations. It's important in determining an infestation by looking for molted shells since, other than the slight web, this is the first sign of an established Brown Recluse NEARBY. A spider can be in plain sight if they are not disturbed. As surprised as I am, a specimen molted in the lab twice in 10 days. I would have never believed that if I hadn't seen it with my own eyes. The picture below is possibly only 3 weeks of a Brown Recluse lifetime.

The spider's ability to go for months without food, water, or even possibly air is remarkable. It's been reported that a Brown Recluse can go as long as 6 months without food or water. I had a specimen (BR2-11-04) that survived for 3 months until an unrelated experiment took its life. The specimen was active for about 2 weeks and then it went into the rest position and emitted a clear brown fluid. The spider also showed dehydration wrinkles in the abdomen but it still survived. It's also worth noting that the Brown Recluse does prefer to eat regularly, so the first place to look for the spider is in a place that draws bugs. If the spider finds a termite mound in total darkness, it may reside there, but it prefers to position itself at ground level, under a light. Under a back porch light is the first place to look for the spider. They occasionally prefer a corner. They are the masters of probability and it is most likely that a bug will crawl or fall at a bottom corner. They can also survive on possibility as well. I have seen them in boxes eating spiders dropped by Black Wasps. Closets are a common place to find the spider due almost entirely on moths. Although the closet light is only on for moments per day, it still draws the occasional mosquito or fly and that's all the spider needs to survive. Shaking clothes is an excellent technique since the spider is eager to move out of the article once it is disturbed. They are also likely to be brought into the closet by old clothing and shoes, which adds to why they are there.
There has been to my knowledge no known natural enemy of the Brown Recluse but my experiments found 2 Brown Recluse killers so far. The discovery is very exciting and a huge step in controlling the spider naturally. I expect to discover many other "Brown Recluse killers" with more attention to that theory. It has been reported that Spitting Spiders are natural enemies. I am trying to confirm that the pictures that I have posted are Spitting Spiders, but it looks like they are not. Spitting Spiders are known "spider killers". It has been rumored that brown crickets were the natural enemy with no factual results. We do have to be careful with the term "natural enemy" until we can prove that anything actually seeks and destroys something else.

I have to admit that this one had me wondering because it was so hard to see. Note the dark spots on the joints and lack of distinct fiddle markings. I put this one in a jar and it spun a web, which Brown Recluse do not do and died in about a week. If your spider lives longer than a week, it is more likely a Brown Recluse.

This example probably is mistaken the most and an unknown species to me, but common in Texas. Note that it does have a fiddle on its back, but it points in the wrong direction and the color is not correct. This species has the rest position characteristics (6 front legs pointing forward and the rear 2 pointing backwards). The legs are much too thin and long. That's why it's important that the spider you identify has all of the Brown Recluse characteristics.

Not Brown Recluse

Again, it has a fiddle, but not the correct one.

Not Brown Recluse

Note the babies. This species is also a killer of the Brown Recluse but not as ferocious as the Jumping Spider. This spider killed a Brown Recluse under lab conditions and emitted a clear sticky substance once it was prepared for a slide. I have to admit that it is unlikely that this spider kills any substantial numbers of Brown Recluse because a Brown Recluse must become trapped in its web.

Not Brown Recluse

This is a Wolf Spider and often mistaken as a Brown Recluse since it is common and has some markings. This spider is prey of the Brown Recluse and an experiment sent this large spider running in hot pursuit by a medium size Brown Recluse.

A common house spider (baby Wolf Spider) was placed in the jar with the starving Brown Recluse specimen (BR2-11-04). The Brown Recluse struck the spider then waited for the toxin to kill the common spider before sucking it dry. I caught the common Jumping Spider (Phidippus audax) which is black with a white dot on top of its abdomen. I prepared to add the Jumping Spider (JS5-2-04) to the list of Brown Recluse victims and dropped it in the jar with BR2-11-04. The Jumping Spider pounced on the Brown Recluse once then attacked again grabbing it by its throat until it was dead. I really hated to lose my oldest specimen, but elated to find a Brown Recluse killer.

It's important to become slightly sidetracked and study the Jumping Spider considering its important characteristics. My theory is that this spider is very important as a household friend especially in the instance of a Brown Recluse infestation. The jumping spider is superior tactically to the Brown Recluse with its jumping ability and obvious excellent eyesight. A person could conceivably live with the fact that introducing a jumping spider in the house is better than a brown recluse infestation, but is it worth it in the long term to have a jumping spider infestation? The answer is, there is no long term jumping spider infestation. A jumping spider can only live 3 days without eating, which means it would eat at least 1 Brown Recluse per day. That is unless there is a cockroach infestation which the Brown Recluse and Jumping Spider would share in the extermination until only the starving Jumping Spider was left. If the homeowner was unnerved by seeing the Jumping Spider on occasion, they could rest assured that when they stop seeing them, the job is finished and all spiders are gone. The Jumping Spider would be most effective in the closets with the clothes where pesticides can not penetrate and the greatest risk of a bite is most likely. Brown Recluse live on moths in closets and the extermination of moths and Brown Recluse is a win win situation. Besides, would a person rather be scared by a Jumping Spider or bitten by a Brown Recluse.
Is pesticide the answer? I know I'm going to catch a lot of flack from the bug killers so I offer a challenge when they are ready and some homeowner is ready to permit Brown Recluse specimens hidden in their home. Of course they will be in small escape proof containers. My answer is no, pesticide is not the answer although some good results have been reported. I'm going on the theory that the resilient Brown Recluse must come in direct contact with the pesticide. A fogger has the best chance of making contact with the spider but who wants a fogger set off in their closet not to mention that a spider inside the clothes would probably not be affected. I also worry that spraying will bring the spiders out of their hiding place and on the move, possibly into the bed. I think the roaming; hunting, killing Jumping Spider is the answer.

Reports are that the Brown Recluse is nocturnal and Jumping Spiders are daytime feeders. All Brown Recluse that I have come across have either been in plain sight or just out of the light. Nocturnal does not mean they come out at 8 PM and go to bed at 6 AM. They don't have to be active to be found and attacked. As sad as it is, I have followed a Jumping Spider for a lot of one day. It went through the entire room (across the TV, up to the ceiling, across the floor, under the chair, behind the bookcase, under the dishwasher) then the phone rang and I decided it best to find something else to do rather than tell my friend that I was tailing a jumping spider. The point is that the Jumping Spider penetrated Brown Recluse territory. Would it engage the Brown Recluse? I think so. I have also seen a Jumping Spider IN a closet. I wonder what he was up to in the dark. More questions than answers for sure, but I'm on it.

Another accidental experiment was performed where an unknown spider shared a jar with a Brown Recluse. I assumed of course that the unknown spider would be found dead, but to my surprise, the Brown Recluse lost that battle too. If you have arachnophobia, I can understand your seek and destroy method but education and diligence is the best approach.

Brown Recluse relies entirely on human error for infestation. Every infestation can be traced in my opinion. Brown Recluse simply do not pack their Sampsonite and walk out the door on an adventure. You have to ask yourself:

As you can see, the list goes on and on as to how an infestation occurs and it's impossible to avoid all of these scenarios but with a little diligence, the risk can be reduced. Further investigation found the Brown Recluse to be thick in another area at my discovery location. It appears that the spider first infested this other area in a garage by way of an old box of junk.

Keep beds away from the wall and do not use under the bed for storage. Be very careful when you replace your old mattress with one from storage or someone else's garage. If you are totally paranoid you can wrap tape backwards around the bed legs so that the adhesive points outward to catch spiders. This is not a proven strategy but if you have an infestation, anything is worth trying. Do not sleep on the floor, especially after moving to a different residence. Never ever put on clothes that have been lying on the floor. I personally quit that habit many years ago when a pair of shorts that I put on from the floor was inhabited over the night by a scorpion. That story had a happy ending with a quick shake and a plop on the tile floor. That's also the hard way to test your heart. Don't bring clothes from storage into the closets, and that washing machine and laundry storage in the garage is probably not looking like such a good idea. If a garage is infested, you really don't have any choice but to try a thorough extermination effort before the house inevitably becomes infested. It's important not to just bug bomb the garage but to create an extermination barrier between the house and connected garage to prevent the spiders from simply moving into the house. Be careful what you put in your closets, especially shoes from someplace else. If you have unused clothing and camping gear, it's best to have a dedicated room for those items and the room should be bug bombed regularly. Camping gear and other such articles should be stored in a sealed trash bag if the items are to be kept in the garage or storage. Be especially careful with camping gear, which is usually stored in garages and storage rooms. Don't lay a jacket down in a garage or shop. Shake out everything, since the Brown Recluse are willing to get out of disturbed clothing as bad as you want them out. In the shop, store gloves, ear protection, shoptowels, and aprons in a sealed container. Either wear the items or shake them out and put them away. Do not lay down gloves even for a second. To shake out gloves, grab the tip of the middle finger and beat the glove on the tip of your boot then wring the gloves like you're trying to get water out of them. You'll probably be more inclined to go to such drastic steps when you verify that you have an infestation. The best defense is of course to avoid an infestation. If you must deal with an infested area, which I do not recommend, do it in the winter. These spiders are very, very fast and some are very small.

Don't panic. Remember, there is NO evidence that the Brown Recluse is responsible for any bites. Why haven't all of these bitten victims caught the spider that bit them? Wouldn't the crushed spider still be in the bed or shoe? WHERE'S THE EVIDENCE? Thank God our constitution isn't handled the way the Brown Recluse is. Will I make every effort to avoid them and encourage the same? Yes. Will I run to the doctor and say I was bit by a Brown Recluse or will I think about when I scratched the heck out of that mosquito bite with my hands that had been digging in the dirt. Let's think about this. Thanks for stopping by. Come back soon to see how my experiment of releasing 100 jumping spiders in a Brown Recluse infestation turns out.

Nice Jumping Spider Site	Bite Pics Thumb
Jumping Spider Prey Attack Path	Bite Pics Arm
Brown Recluse Misidentify And Territory	Spider Killer Questions And Other Data