Black Widow Identification and Prevention

By: Date:

The black widow: it’s what many people envision when they think of a dangerous spider. Here at Blue Sky, we often get calls from people who are concerned that they may have seen black widows in their homes, so we wanted to provide you with the tools you need to identify and prevent them.

Male black widows are harmless, but venom from the female black widow can be highly toxic to humans. Reactions to black widow venom can vary depending on the location of the bite, the amount of venom injected, and individual sensitivity to the venom. For this reason, it is important that you keep a lookout for black widows in your home, and call us if you think you may have an infestation.  If you are bitten, contact your local poison control center immediately, and attempt to capture the spider for identification.


Adult female black widows are glossy black to very dark brown in color, with a large rounded or oval abdomen. The characteristic orange or bright red hourglass marking is found on the underside of the abdomen. When mature, female black widows can measure up to 1.5 inches, including leg span.

Male black widows are roughly one-third the size of females, and also have the red hourglass marking. They are light brown or tan in color.

Newly hatched black widows are white with black spots on their abdomens, with a cream-colored hourglass marking. As they mature, they become cream and brown striped.

Black widows are common in the warm desert environment in Arizona, and like to build their webs in cool, sheltered areas. You may see black widow webs under rocks, under steps, or around decking near your home. They are nearly always outdoors, but sometimes black widows will build their webs in a secluded indoor area, like a garage, basement or closet. Black widow webs are not uniform in nature and have a cobweb appearance.


Black widow spiders do not hunt humans, and will usually only bite when provoked or trapped, or when they are protecting their eggs. For this reason, you should be careful when moving items that have been in an undisturbed area for a long time, such as stored lawn furniture or flower pots.

Control other pests around your home to remove the food source for black widows. If you take care to get rid of pests such as roaches and crickets, you will remove an easy food source for the spiders and they will have to relocate.

Keep your outdoor areas clean and free of debris, and reduce the areas of suitable habitat around your home. Clean up wood piles or piles of yard waste, and regularly clean empty, enclosed spaces near the foundation of your home. Tidy up your storage areas, and clean up any unneeded items, boxes or stacks of debris in garages, sheds and basements. Keep landscaping plants trimmed and away from the foundation of your home.

If you see webs, use a broom or vacuum to destroy them. You can use a fly swatter to kill black widows if you see them around your home.

If you fear that you might have a black widow infestation on your property, you can always try to capture a specimen and bring it in to us for identification.  Or, try to take a picture and post it to our Facebook page – we will help you identify it! If you have black widows in or around you home, the best way to get rid of them is to call the professionals at Blue Sky.

Our premium service includes several treatment options that provide effective black widow control. We will target their common nesting areas, and knock down any of the webs we see during our thorough inspection of your home.