The Black Widow is a venomous spider most often found in North American deserts across the United States. Other species of Widows can be found in temperate climates around the world. The adult females are about 1 1/2″ long and are easy to identify by the red hourglass shape on their abdomen. Males and immature spiderlings are harder to identify, as they are often brown with orange and white markings and are smaller than the females. Only the females are considered dangerous.
Their venom can be 15 times stronger than some rattlesnakes and it’s considered to be the most poisonous spider in North America. They are not aggressive and usually only bite in self defense, so little venom is injected. Most people bitten don’t usually die. But a black widow spider bite can cause pain, nausea, cramping, sweating, swelling and difficulty breathing. If bitten you may feel something like a small pinprick or nothing at all. It’s possible to not even know you’ve been bitten, until hours later when the symptoms finally start to appear.
Black Widow spiders prefer dark, undisturbed, secluded areas, both indoors and outside to nest in. Outside they can be found under rocks, low bushes, wood piles, trash, outhouses, barns and holes in the dirt. Indoors they can be under or behind furniture and may be brought inside in a stack of firewood. The egg sacks found in the webs, look like small silken balls and can contain from 25-900 eggs. The babies emerge after an average incubation of 20 days. The spiderlings are cannibalistic after about a week and only a few actually survive to leave the nest. Their life span averages 1 to 1 1/2 years. The Black Widow spider eats all types of insects; grasshoppers, flies, other spiders, centipedes, pretty much anything that gets caught in the web.
There’s only a few species in which the female actually eats the male after mating, and even then it rarely happens.