The brown recluse spider, Loxosceles reclusa, often generates concern due to the potential severity of its bite. This spider is naturally reclusive, preferring to avoid human contact. Its presence in homes results from specific environmental conditions and resources that draw it in. Understanding what attracts these arachnids is the most effective way to reduce the likelihood of an encounter. Primary factors include undisturbed shelter, available prey, and accidental transportation into a dwelling.
Confirming the Brown Recluse Identity
Misidentification of the brown recluse is common, often leading to unnecessary fear or misdirected control efforts. Accurate identification relies on specific physical markers, as many other common spiders have a similar brown coloration. The most distinguishing feature is the arrangement of its six eyes. These eyes are configured in three pairs, or dyads, arranged in a semicircle on the front of the cephalothorax, unlike most spiders that have eight eyes.
The famous violin or fiddle-shaped marking is present on the dorsal side of the cephalothorax, with the neck pointing toward the abdomen. This marking can be faint, especially on younger spiders, and similar patterns appear on other species. A more consistent identifier is the lack of a coloration pattern on the abdomen and the absence of spines on the uniformly light-colored legs. The spider’s native range is restricted to the south-central and Midwestern United States, from Nebraska to Ohio and south to Texas and Georgia.
Environmental Factors That Draw Them In
Brown recluse spiders are naturally attracted to spaces that mimic their outdoor habitats, such as under logs or rocks, by providing dark, dry, and secluded conditions. Indoors, this translates to undisturbed areas like attics, basements, wall voids, and crawl spaces. These spiders seek out stable environments protected from the elements.
Clutter is a major attractant because it provides an abundance of hiding spots and surfaces for their irregular, sheet-like webs. They use these webs as retreats for resting and egg-laying, not for catching prey. They particularly favor cardboard boxes, which mimic the rotting tree bark they inhabit in nature and offer numerous crevices for shelter. Since they are primarily nocturnal hunters, they thrive in areas not frequently cleaned or disturbed by human activity, allowing them to remain hidden during the day.
Food Sources and Accidental Transportation
A consistent food supply is a strong secondary attractant that encourages brown recluses to establish a population within a home. These spiders are active hunters and scavengers, primarily feeding on soft-bodied insects such as crickets, silverfish, cockroaches, and moths. A home with an existing pest issue inadvertently becomes a reliable hunting ground, signaling a sustainable environment. They are also capable of cannibalism and will scavenge dead insects, demonstrating an opportunistic diet.
Beyond seeking food and shelter, the most common way brown recluses enter a home is through accidental transportation, or “hitchhiking.” They are often carried into new locations via items moved from sheds, garages, or storage units. This commonly includes boxes, furniture, stored clothing, and bedding where the spiders have been resting. Since the spider will hide in clothing or bedding left on the floor, this ingress method can lead to defensive bites when the item is subsequently used.
Practical Steps to Reduce Attraction
Reducing attraction factors involves a multi-pronged strategy focused on sanitation, exclusion, and pest control. Eliminating clutter in storage areas, like basements and attics, removes the undisturbed hiding spots brown recluses seek for harborage. Replacing cardboard boxes with tightly sealed plastic containers removes a preferred nesting material.
Controlling the spider’s food source is an indirect but effective method of reduction. Implementing general pest control to reduce populations of soft-bodied insects like crickets and silverfish decreases the home’s appeal as a hunting ground. Sealing exterior entry points, such as cracks in the foundation, gaps around utility pipes, and loose-fitting doors and windows, prevents both the spiders and their prey from moving indoors. Inspecting items brought inside from outdoor storage, such as firewood, boxes, or seasonal clothing, is a direct action to prevent accidental transportation.