Black Widow Basics

Spider ControlWe all know black widows are dangerous, but do you know how to spot one, and what to do if you start finding them around your property? Learn more about these dangerous spiders, so you can protect yourself and your family from their potentially fatal bite.


Female black widows are approximately 1.5 inches long, with shiny black bodies and a red or orange-yellow hourglass marking on the underside of their round abdomens. Males are about half the size of females and lighter in color, with red or pink spots on their backs. There are actually 31 species of “widow spiders,” including red widows and brown widows, but the black variety are the most dangerous.

Black widows can be found in most of the world’s temperate regions, including Africa and Australia, southern Asia and Europe, most of South America, and parts of the United States.  The spiders tend to inhabit dark, dry shelters like barns, garages, basements, outdoor toilets, hollow stumps, rodent holes, trash, brush and dense vegetation.


Black widows mate in late spring, but are otherwise primarily solitary. Although females can live up to three years, males typically only live for one or two months. The female often kills and eats the male after mating, the behavior that grants the species its name. The female lays 200 to 900 eggs in a papery sac that hatch after 30 days. Few hatchlings survive the three-month development to adulthood: the baby spiders are also cannibalistic. However, because the baby spiders tend to hatch at once, late spring and early summer are particularly dangerous times to run across the spiders, as it’s very possible they are only one of hundreds from a nearby nest.

Black widows eat flies, mosquitoes, grasshoppers, beetles, caterpillars, and even other arachnids. Once the prey is ensnared in the web, the spider wraps the prey in silk, then uses its fangs to puncture the prey and inject digestive enzymes that liquefy the corpse, producing a fluid the spider can consume. While their tendency to eat pests might make them sound like a desirable houseguest — after all, some spiders are — this breed of spider is dangerous enough that it cannot be tolerated anywhere humans live.


Black widows are highly poisonous, with venom that is 15 times stronger than that of a rattlesnake. Fortunately they are only likely to bite humans when disturbed, and only the female’s bite can be considered a threat to human health. The bites are rarely fatal, though they still pose a great risk to the very young, the ill, and the elderly. Initially no more than a pinprick, more intense pain begins within minutes and spread to other parts of the body. Additional effects can include nausea, sweating, back and abdominal pain, muscle aches, elevated blood pressure, and difficulty breathing. While the pain generally subsides in eight to twelve hours, other symptoms may persist for several additional days. If you suspect that you have been bitten by a black widow spider, it is important to seek medical care immediately.

To help prevent black widow spiders on your property, keep brush and dense vegetation to a minimum, and remove hollow stumps and fallen trees as soon as possible to limit these potentially tempting homes. If you suspect you have black widow spiders, call a pest control professional to schedule a consultation to help you make your home a safer place.

Proudly serving the greater Chicagoland area in Illinois and southeast Wisconsin, the professional exterminators at Aerex Pest Control understand the habits of different types of pests and use that knowledge when developing a pest control program that is best suited to your home and your particular problem. Our technicians are professional, state certified, licensed applicators. Call today for your free consultation 847-255-8888 or click here for a free quick quote.

Now hiring experienced, licensed, pest control technicians! To apply, please call 847-255-8888.