How to Identify a Black Widow Spider

It’s never fun to realize that spiders are running amok in your home, especially when it’s a dangerous species like a black widow. Bites from these critters can lead to nausea, muscle weakness, and even seizures in the worst cases—which is why being able to spot them before any of that happens is of the utmost importance. The following guide will teach you exactly how to identify a black widow spider, how to prevent them from showing up in your house and what to do if they’re already there.

Start by Looking for Signs of a Spider Infestation in General

Spider infestations don’t just happen out of nowhere. They take time to form, and a few signs will help you determine whether or not such an issue is present—or developing—in your home. Spotting a spider—living or dead—is the first clue to look out for, but the following indicators will tell you if it’s a one-time problem or something much larger. 

• Excess cobwebs. While seeing the occasional cobweb around your home is normal, you might have an infestation if they occur more frequently than normal. 

• Fewer flying insects than normal. Spiders feed on bugs like flies and mosquitoes. While they’re a nuisance to have around, seeing fewer than usual could mean more arachnids in your home eating them up. 

• Spider nests or egg sacs. Spider nests resemble densely packed cobwebs and usually protect a delicate gray- or cream-colored egg sac. You’ll usually find these in tight corners or crawl spaces where they’re less likely to be agitated by external forces. 

Familiarize Yourself With Black Widow Characteristics 

Once you’ve determined whether or not you have a spider infestation, it’s time to figure out what species you’re dealing with. The following characteristics are unique to black widows, and knowing them will help you easily differentiate this spider variety from others. 

Coloring and Patterns

As their name suggests, black widow spiders will typically be dark black—though females of this species may sometimes be slightly brown. Often, but not always, they’ll also have a red hourglass-shaped pattern on their belly. Remember to keep your distance when identifying spiders of any kind. To spot that unique pattern, you’ll either need to safely trap a live specimen or find a dead one to take a closer look. 

Number of Legs and Eyes

While some toxic spiders may only have six eyes and legs—like a brown recluse—black widow spiders will always have no less than eight eyes and legs. 

Size

The size of black widow spiders ranges from 1 ½ inches to 1 3/8 inches. Male widows will typically be smaller than their female counterparts. 

Shape

Black widow spiders have a round abdomen attached to a small, circular head. Their legs are proportionally much larger than the rest of their body.  

Region 

This spider variety can be found throughout the continental United States. It prefers warmer, temperate climates and is spotted more frequently in Southern and coastal states than elsewhere. 

Learn What Attracts Black Widow Spiders

What attracts spiders is the same across all species. Take steps to minimize the following stimuli to minimize the presence of black widows and other spiders in your home. 

• Excess insects. While a sudden disappearance of insects in or around your home is a sign there are a lot of spiders on your property, letting bugs run wild will almost certainly attract arachnids down the line. Take steps to minimize insect populations before the spiders step in to do the job by trying out some easy pest control solutions. 

• Cluttered spaces. Empty cardboard boxes or disorganized storage spaces are havens for spiders because of their small, safe spaces for nesting and laying eggs. 

• External debris. Spiders also like wood and dirt piles for the same reason they like cardboard boxes—they have plenty of nooks and crannies for breeding. 

• Small openings and unsealed cracks or gaps. If there’s an opening in your home big enough for spiders to squeeze through, you can be sure they will. Fortunately, sealing such cracks with a bit of caulk and a little elbow grease is easy. 

Take Steps to Prevent Black Widow Infestations 

There are several things you can do to repel spiders of all species. For starters, try natural spider repellents like applying lavender, peppermint, or eucalyptus essential oils to possible entry points or favorable nesting zones. If you need something more intensive to deal with a current infestation, consider placing sticky traps in hotspots. 

Getting Rid of Them on Your Own vs. Hiring a Pro 

While it is possible to contain or eliminate a current infestation all on your own, you must take steps to keep yourself safe in the process. That involves wearing gloves, hats, long sleeves, and full-length clothing and treating problem areas with natural or chemical insecticides before attempting removal. 

If you’d rather avoid the risks associated with such a project, let a pest control professional near you take care of the job instead. Pest control costs, in general, can range anywhere from $50 to $500, but you can expect to pay between $100 and $300 in spider extermination costs. 

What to Do If You’ve Been Bitten 

If you suspect a black widow spider has bitten you, clean the area with soap and water and contact a poison control center for further guidance. They will likely recommend applying an ice pack to the affected area for ten minutes, staying still as much as possible, and tracking your symptoms. When in doubt, head to the doctor before things worsen. Try to identify the spider and the time of the bite to get the best diagnosis.