Characteristics of Black Widow Spiders

Black Widow Closeup from Top

Black widow spiders exhibit typical characteristics of spiders-eight legs, no wings, no antennae, and like most spiders, eight eyes. Their other physical characteristics vary depending on whether they are male or female.

Of the two genders, the female black widow is the one that most people probably recognize. They are usually black in color with a characteristic large, shiny, and very rounded abdomen. They have unique hourglass-shaped markings on the underside of their abdomens. These can vary in color from yellowish to orange to red.

Male black widows are about half the size of the female. They are sometimes lighter in color and have patterns or markings on the dorsal side of their abdomen, usually spots and lines that branch out to the sides. Young black widow spiders of both sexes resemble adult males.

Many people fear black widow spiders because of their dangerous bite. It is the bite of only the adult female black widow that is harmful to humans. People's reactions to black widow bites can vary, depending on such factors as his/her sensitivity, the amount of venom injected, and the location of the bite. If treated, black widow bites are rarely fatal and rarely cause serious long-term problems.

Instead of hunting their prey, black widow spiders spin webs to trap it. They eat a variety of insects such as beetles and cockroaches. These webs are an irregular mass of fibers with no obvious pattern. The webs are, on average, about a foot in diameter and have a small spot in the middle where the spiders wait for prey. A web is usually situated near the ground in a dark, sheltered location.

Outside, black widows tend to live in protected areas, such in tree stumps, under rocks, decks, or in woodpiles. They also prefer the shelter of outbuildings like sheds, tree houses, or barns.

Indoors, black widows prefer undisturbed parts of homes, such as garages, basements, or crawl spaces. They like cluttered areas because they can find more insects to eat.

Black widow spiders are more commonly found in the warmer parts of the United States. However, they can be found along the entire eastern seaboard and westward to Texas, Kansas, and Oklahoma.