The Most Effective Ways To Keep Brown Recluse Spiders Out Of Your House

As their name indicates, brown recluse spiders (LOXOSCEES RECLUSA) would prefer to hide and avoid interacting with us. Occasionally, we may find one indoors or in our yards, especially in certain parts of the Southeast. “Established populations of brown recluse spiders are distributed throughout the southern and central US,” says Johnalyn Gordon, PhD, assistant professor of urban entomology at the University of Florida Institute of Food and Agricultural Sciences. “In the Southeast, the states that are most within this distribution range are Georgia, Alabama, Mississippi, Louisiana, Arkansas, Tennessee, and Kentucky. Outside of this range, brown recluse are very rarely encountered.”

Occasionally, they do show up outside their native range, transported by hitchhiking in boxes or furniture. “They might be able to establish in a new home or building, but they have poor dispersal abilities,” says Angela Chuang, PhD, assistant professor in the departments of environmental science and studies, biology, at Washington College.  “This can lead to cases where a single building has them, but they are otherwise not spreading to other buildings in the neighborhood.”

This means that no matter what you’ve heard or seen on social media, you don’t have to worry about a sudden new “invasion” of brown recluse spiders if one has been found outside its native range, says Chuang.

How To Identify Brown Recluse Spiders

One of the challenges with brown recluse spiders is that they’re tricky to identify because they’re fairly nondescript. “The common wisdom is to look for ‘violin’ markings on their ‘back,’ which is why they’re sometimes known as ‘fiddleback spiders,’” says Chuang. “But this can be difficult for the average person to see. This is especially true if the spider is already dead and desiccated.”

The eyes are the best identifying feature, though it’s difficult to be certain about what you’re seeing without the use of magnification. “While most other spiders have eight eyes, arranged in four pairs, recluse spiders, including brown recluse, have six eyes, arranged as three pairs, with two in the center and two on each side,” says Gordon. Otherwise, these brown to tan-colored spiders are not particularly large, about the size of a quarter, legs and all. The legs are thin and often held out flat to the sides.

Other harmless brown spiders often are mistaken for brown recluse spiders. Some even have similar violin patterns, such as the giant huntsman spider (which is much larger—about the size of a drink coaster!) or wolf spiders and fishing spiders. The Southern house spider also has similar markings and is common in southeastern buildings, says Chuang.

If you suspect brown recluses, get a positive ID before undertaking any management solutions. “There are a lot of harmless brown spiders that eat the numerous arthropods that find themselves in our homes,” says Chuang. “But these other spiders do not warrant management, so it would not make sense to invest money, time and resources into relatively rare event. For example, wolf spiders and various ground spiders blunder into our homes but do not ‘live’ in them, so it does not make sense to ‘manage’ them, besides capturing and throwing out the occasional unlucky individual.”

Do Brown Recluse Spiders Bite?

Occasionally, but biting is a defensive measure. “Like black widows, brown recluses have a much worse reputation than they deserve,” says Chuang. “Bites occur in situations where someone’s unprotected skin puts pressure on the spider, causing them to bite in distress, in an attempt to be released.”

This might happen if the spider is trapped against your skin with a towel or piece of clothing, or if they have fallen into a shoe, or if they’re on furniture where you place your arm. It’s also somewhat more common if someone picks up wood from a woodpile or moves yard items without wearing gloves, says Chuang.

Reactions to bites from a brown recluse, like any spider or insect, can vary. “In most cases, the bite itself is not painful, and it remains localized, healing in a few weeks,” says Gordon. “However, the venom is a cytotoxin, and, in some cases, bites can lead to necrotic lesions requiring medical attention.”

Because it’s nearly impossible to diagnose a spider bite without the spider itself, try to collect it if you believe it bit you, says Gordon. Also, if you experience any concerning symptoms,  such as fever, sweating, chills, or difficulty breathing, contact your doctor right away.

Where Do Brown Recluse Spiders Hide?

Brown recluse spiders, as their name indicates, are a little “shy” and like to hide in warm, dry, quiet areas. They prefer dark, rarely-disturbed rooms, such as the basement, guest room, or storage areas and are active at night. Outdoors, they can be found in rock piles and leaf litter, says Gordon. They also may be found in sheds or under decks.

How To Keep Brown Recluse Spiders Away From Your Home

Try these tips from Gordon and Chuang to make your home less welcoming to brown recluse spiders (and spiders, in general):

• Seal entry points. Make sure screens are in good repair, and check for gaps in weather stripping and door sweeps.
• Deal with indoor insect populations. “Brown recluses can only increase to high densities if there are a lot of insect prey around, so it may be worth managing the insects first,” says Chuang. Bottom line: No food = not a good place for spiders to live.
• Keep your home clean. Dust regularly and remove webs in various corners of a home or property with sticks.
• Get rid of clutter. These spiders like to hide in stacks of collapsed boxes, shoe boxes, or piles of clothing. Eliminating clutter in unoccupied areas can reduce their appeal to spiders, along with controlling any indoor food sources like crickets, cockroaches, and silverfish, says Gordon.
• Keep wood and rock piles away from up against the house. This makes it less likely spiders will find their way indoors.
• Always wear gloves and long sleeves when working outdoors or cleaning clutter. Choose cloth, leather, rubber or anything thick that will protect you from accidental bites, says Chuang.
• Forget about repellants. No research yet has found commercial or DIY repellants that keep spiders away, including a popular social media hack of using lemon oil, which a study found showed no effect.
• If you have a large population of brown recluse spiders, hire a professional pest control company. “Serious infestations often require a pest management professional to inspect the space and develop an integrated management strategy,” says Gordon.