Black widow spiders often evoke a sense of unease, leading many to wonder about their presence in local environments. For residents of Maryland, a common question arises regarding whether these spiders inhabit the state. Understanding the distribution and characteristics of black widows can help alleviate concerns and promote awareness.
The Black Widow’s Presence in Maryland
Maryland is home to two native black widow species: the Southern Black Widow (Latrodectus mactans) and the Northern Black Widow (Latrodectus variolus). The Southern Black Widow’s range extends northward into Maryland, while the Northern Black Widow is frequently found throughout the Mid-Atlantic states, including Maryland, being particularly prevalent in the northern parts of its habitat.
While black widows are present across Maryland, they are typically found outdoors and infrequently venture inside human dwellings. On occasion, they might be inadvertently brought indoors within items that have been stored outside, such as boxes, flowerpots, or firewood.
Identifying Black Widows
The adult female is typically jet black and possesses a shiny, glossy appearance, often described as toy-like. Her body is usually about a half-inch long, with a noticeably plump, rounded abdomen.
The most recognizable feature is the bright red hourglass-shaped marking located on the underside of her abdomen. For the Southern Black Widow, this hourglass mark is usually a single, connected shape. In contrast, the Northern Black Widow’s hourglass may appear as two distinct red spots or triangles. Female black widows often hang upside down in their webs, which prominently displays this warning coloration. No other spider in Maryland shares this unique combination of features, making identification relatively straightforward.
Male black widows are considerably smaller than females, typically measuring about one-eighth to one-quarter of an inch, and possess more elongated bodies with proportionally longer legs. Unlike the females, males generally do not have the iconic red hourglass marking. Instead, they often exhibit patterns of white, red, or yellow stripes and spots on their abdomens. Juvenile black widows also display varying patterns of orange, brown, and white before developing the adult female’s characteristic black coloration.
Common Habitats and Encounters
Black widow spiders prefer to establish their irregular, messy webs in dark, secluded, and undisturbed locations.
Outdoor Habitats
- Basement window wells
- Beneath lawn furniture or porches
- Inside garages and tool sheds
- Within woodpiles, rock piles, or trash piles
- Water meters
- Under eaves
- Within brush or leaf piles
Indoors, while less common, black widows might be found in undisturbed spaces such as basements, crawl spaces, closets, or dark corners, particularly if there are openings to the outdoors. Their webs are typically built near ground level and are known for their strength and stickiness.
Black widows are not aggressive and will generally attempt to escape. Bites usually occur when the spider feels threatened, such as when it is accidentally touched or pressed. Instead, using tools or isolating the area can help manage the situation safely. When working in areas where black widows might reside, such as moving firewood or cleaning out sheds, wearing gloves and being observant can help prevent accidental encounters. For removal or if an infestation is suspected, contacting a professional pest control service is the safest and most effective approach.