Encountering a brown widow spider often raises questions about its threat level and whether removal is necessary. Understanding its characteristics and behaviors provides practical guidance for managing its presence.
How to Identify a Brown Widow
Brown widow spiders typically display a mottled coloration, ranging from tan to brown, sometimes with grayish tones. Unlike the shiny black widow, the brown widow’s body is not glossy. Females often exhibit a dorsal longitudinal abdominal stripe and three diagonal stripes on each side of the abdomen. A distinct hourglass marking, usually orange or yellowish, is present on the underside of their abdomen, differentiating it from the black widow’s vivid red hourglass.
A key feature for identifying a brown widow is its egg sac. These sacs are spherical and covered with numerous silk spicules, giving them a spiky or “puffy” appearance, often compared to a World War II harbor mine or a large pollen grain. In contrast, black widow egg sacs are smooth. Brown widow spiders also tend to have long, slender legs with alternating light and dark bands.
Assessing the Brown Widow’s Threat Level
The venom of a brown widow spider contains a potent neurotoxin, similar to other widow species. However, brown widows typically inject a smaller amount of venom during a bite, resulting in less severe symptoms than a black widow bite. Common reactions include localized pain, redness, and swelling at the bite site, comparable to a bee or wasp sting. More severe symptoms like muscle cramps, nausea, or fever are rare.
Brown widows are generally timid and less aggressive than black widows, preferring to retreat or play dead when disturbed. Bites typically occur only when the spider feels threatened or is accidentally pressed against the skin, such as when reaching into cluttered spaces. Male and immature brown widow spiders are not known to bite.
Safe Approaches to Brown Widow Encounters
When encountering a brown widow spider, various safe approaches can be considered depending on the situation. If the spider is in an undisturbed outdoor area, leaving it alone might be an acceptable option, as brown widows are part of the ecosystem.
For spiders found in unwanted locations, physical removal or relocation is possible. Gently sweep them away with a broom, or use a cup and card to capture and release them outdoors. Vacuuming spiders and their webs, especially with a shop vacuum containing a few inches of soapy water, can also be effective.
If killing is necessary, direct methods include crushing the spider with a shoe or broom. Insecticide sprays can also be used, but a quick direct spray is usually sufficient; excessive use can be unnecessary and potentially affect other organisms. For egg sacs, oil-based pesticides are more effective than water-based ones due to the sac’s hydrophobic silk. In cases of persistent or widespread infestations, professional pest control services can provide thorough identification and elimination strategies.
Minimizing Future Brown Widow Presence
To reduce future brown widow encounters, proactive measures focus on modifying their preferred habitats. Removing clutter like storage boxes, woodpiles, and debris from around the home and yard eliminates many potential hiding and web-building sites.
Storing items in sealed plastic containers instead of cardboard boxes in garages and sheds deters them. Sealing cracks and crevices in foundations, windows, and doors prevents spiders from entering structures. Ensuring proper screening on vents also restricts entry.
Regular cleaning, including sweeping webs and vacuuming corners, helps disrupt spider activity. Reducing insect populations around the home, which serve as a food source, makes the area less attractive to spiders.