Where Do Black Widows Live and What Are Their Behaviors?

Updated on October 7, 2018
greenmind profile image

I have studied insects for nearly forty years, and I have also done battle with my share of garden pests.

A close-up photograph of a female black widow. Note the robust body, long black legs, and red hourglass.
A close-up photograph of a female black widow. Note the robust body, long black legs, and red hourglass.

Black widow spiders, scientific name Latrodectus mactans, are among the most venomous of all arachnids. They are also among the most poisonous species in North America, and their bite can be fatal in some cases. If you found a spider and you suspect it may be a black widow, this article will help you identify your specimen. Black widows are relatively rare, and most of us will never see one, but if you do see one, you'll want to know exactly what you're dealing with!

I have been working with insects and spiders for almost 20 years, and I get a lot of questions about black widow spiders. What do black widows look like? Where do black widows live? Is the bite of the black widow spider fatal? These are all excellent questions. In this article I hope to answer at least some of your questions about these much-feared poisonous spiders. If you ever wondered what it's like to get bitten by a black widow, or the safest way to pick one up (it's not with your fingers), then this article will address your concerns.

Questions This Article Answers

  1. What do black widows look like?
  2. Where do black widow spiders live?
  3. What makes it a spider?
  4. What are the different body parts of a spider?
  5. How are male black widows different from females?
  6. Do black widows spin webs?
  7. Why do these spiders have fangs?
  8. How common are black widow bites?
  9. What's it like to be bitten by a black widow?
  10. What are the symptoms of a black widow bite?
  11. What's in the black widow's venom?
  12. How do you get rid of black widows?

1. What Do Black Widows Look Like?

Black widows are large spiders that spin tangled webs in sheltered places, both in nature and in your house. The distinctive sign of the black widow is a bright red hourglass marking on the animal's ventral side (the "bottom" or underneath). It's your surest guide to black widow identification—no other spider has it. In the natural world, bright red, orange, or yellow markings are universally used to signify protection by venom or caustic chemicals in the insect's haemolymph, or blood. This, in effect, tells everyone to "stay away from me, or you'll be sorry." But the classic hourglass shape is only one morph that spiders in the black widow's genus display. There are a couple of other variations that still serve the purpose of warning away predators.

If you ever get this close to a black widow, you'll see the true beauty of the species.

2. Where Do Black Widow Spiders Live?

Black widows typically live in your garage or your basement. They prefer dark, sheltered corners where they can spin their tangled webs and wait for the moths and other insects that make up their diet. Black widows do not want you messing with them. In fact, they view any interaction with you as a threat to their very existence. This is why the spiders will bite you—it's the only means of self-defense that they have.

Black widows live where you typically don't go, so you'll only encounter them when you're cleaning out a garage, or reaching into a dark corner of a basement. So be careful! If you make sure you can see where you're putting your hand, then the chances are pretty slim that a black widow will get her fangs into your flesh.

3. Black Widow Biology: What Makes It a Spider?

Black Widow identification begins with a question: What defines a spider? Spiders are a kind of arthropod, a huge group of animals that includes water-dwelling organisms like crabs and shrimp as well as all insects, including butterflies and moths. Spiders form a subset called "arachnids." They are separated from other closely related insects by several features: spiders have eight legs instead of six, two body sections instead of three, most spin webs with a special organ called a "spinneret" located at the tip of the abdomen, and all spiders are venomous. The venom of most spiders is only effective against the small invertebrates that they feed on, but a few have poison that can hurt vertebrates like humans. The black widow is one of a very few spiders with venom capable of seriously hurting humans.

4. What Are the Different Parts of the Spider?

Part
Description
1. Fang (chelicera)
The spider's fangs are sharp and deadly.
2. Venom gland
The glands connect to the fangs for quick delivery.
3. Brain
The spider brain must connect to many eyes and thus has a quite different structure to our own.
4. Pumping stomach
The stomach breaks down the food into a digestible soup.
5. Forward aorta branch
Like many other species, spiders have an open circulatory system.
6. Digestive cecum
The cecum or caecum is an intraperitoneal pouch that is considered to be the beginning of the digestive process.
7. Heart
They do not have true blood, or veins to convey it. Rather, their bodies are filled with haemolymph, which is pumped through arteries by a heart into spaces called sinuses.
8. Midgut
Glands that cause necrosis in the spider's victims.
9. Malphigian tubules
The Malpighian tubule system is a type of excretory and osmoregulatory system.
10. Cloacal chamber
The posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts.
11. Rear aorta
Supplies haemolymph to the cephalothorax.
12. Spinneret
A spinneret is a silk-spinning organ of a spider or the larva of an insect.
13. Silk gland
The silk gland is used to create the spider's web.
14. Trachea
The trachea brings air into the spider's lungs.
15. Ovary (female)
Where the spider's eggs are produced.
16. Book lung
A book lung is a type of respiration organ used for atmospheric gas exchange.
17. Nerve cord
The nerve cord send sensory information throughout the body.
18. Legs
Spiders have eight, sharp legs that give them incredible balance.
19. Pedipalp
Appendages anterior to the first pair of walking legs.
Click thumbnail to view full-size
Some black widow spiders have different markings! Some are quite beautiful!The northern black widow variation.Another beautiful black widow variation.To identify a black widow, look for the dorsal and ventral markings.
Some black widow spiders have different markings! Some are quite beautiful!
Some black widow spiders have different markings! Some are quite beautiful! | Source
Source
The northern black widow variation.
The northern black widow variation. | Source
Another beautiful black widow variation.
Another beautiful black widow variation. | Source
To identify a black widow, look for the dorsal and ventral markings.
To identify a black widow, look for the dorsal and ventral markings. | Source

5. How Are Male Black Widows Different?

The male black widow, as with many other spiders, is much smaller and less conspicuous than the female. His only real reason to exist is to impregnate the female, and once that's accomplished he becomes just another meal. While this may seem cruel—and is the source of the black widow's common name—it is actually a perfectly rational survival mechanism developed through millions of years of evolution. After all, when food is survival, and the male is no longer needed, the solution is obvious.

Being a male black widow is a tough job. To identify a male, look for the light brown brown body and its disproportionately large eyes.
Being a male black widow is a tough job. To identify a male, look for the light brown brown body and its disproportionately large eyes. | Source

6. Do Black Widows Spin Webs?

The black widow spins a characteristic tangled web in a dark corner. She waits for insects to come along and wander into the web, upon which she grabs her prey, bites it, and sucks the digested insides of the insect out with her hollow fangs. The web is one way to identify black widows, but lots of other spiders spin similar webs, so don't jump to conclusions. Wait to actually see the red hourglass on the shiny black underside of the spider to determine if it is actually a black widow spider.

A black widow building a web.
A black widow building a web.
Female black widow with her prey.
Female black widow with her prey. | Source

Some spiders are capable of subduing even those insects with poison defenses of their own. This large female has captured not one but two wasps capable of inflicting a powerful sting to any predator, but the spider has avoided the stinger and inflicted its own fatal bite. Soon these wasps will be a meal for the spider.

Her venom paralyzes, then liquifies, the insect, and the spider wraps the meal in silk to further control and preserve it. This spider has killed a small insect, and is siphoning out the liquified insides with its straw-like fangs.

A black widow's egg sac.
A black widow's egg sac.

7. Why Do These Spiders Have Fangs?

The fangs of the Black Widow, and all spiders, are believed by some researchers to be a highly evolved pair of legs that long ago became adapted to subduing prey. They are essentially hollow tubes that act like hypodermic needles to inject poison. The poison needs to be powerful and fast acting, since the less the prey struggles in the web, the less damage the spider will have to repair. The toxin also often acts as a liquifying agent, turning the prey's insides into a kind of soup that the spider then sucks up through the same fangs that were used to inject the venom.

Black Widow Eating
Black Widow Eating | Source

8. How Common Are Black Widow Bites?

Black Widow bites are rare, since the animal spends most of its time in its web, unlike the Brown Recluse, which roams at night in search of prey and could wind up under your sheets (a truly unpleasant thought). To be bitten by the Black Widow, you basically need to come to the spider, since it probably won't come to you. This means putting your hand in a dark corner of the basement or garage (or even in a tree stump).

I once found an enormous female who had built a nest in a dead tree, about head level. Once bitten, your prognosis is not good. Fatalities are rare, but you are likely in for several days of the effects of the spider's neurotoxic venom.

Source

9. What Is It Like to Be Bitten by a Black Widow?

Black widows leave two little marks... That's usually all you can see from a black widow bite. The fangs just puncture the surface, but it's enough to deliver the venom.

First-Person Account of Black Widow Envenomation

I've been bitten by a black widow spider. I grabbed a pair of old shoes from the garage, and hastily threw them on over my bare feet, and continued my charge around the house to build momentum to get out the door. About a minute later, I realized that there was some wiggling in the toes in my right shoe, and just as I was about to take my shoe off, I felt a bite on my 2nd toe (it wasn't painful, just a bit annoying). Later, the pain was excruciating.

The medical literature suggests that recovery happens within three to five days. Nights three, four, and five were complete disasters for me. For some completely unknown reason, I was sweating profusely at night. As in, literally soaking through my sheets and changing my sheets three times one night and twice the next. The pain is not just related to body temperature, the experience can vary. Below you'll find the full symptoms of a black widow bite.

10. Symptoms of a Black Widow Bite

Symptom
Description
Local pain
The point of contact feels a burning sensation and can become necrotic.
Muscle cramps
Muscle contract rapidly, causing cramping.
Abdominal pain
This muscle cramping extends to the abdomen causing further pain.
Weakness and tremor
The neurotoxin causes shaking and weakened muscles.
Nausea and vomiting
The neurotoxin causes the digestive system to go haywire, causing vomiting as the body tries to rid itself of the toxin.
Fainting
The pain, nausea, and fatigue can lead to fainting.
Chest pain
As your heart beats faster and faster, your chest begins to hurt. Some people even have heart-attacks.
Respiratory difficulties
As the muscles throughout your body shut down, your lungs are no exception. It will become harder and harder to breathe as your heart goes into a panic.

11. What's In the Black Widow's Venom?

Black Widow venom is complex, and contains a number of compounds that further the evolutionary goal of subduing prey and protecting the animal from predators. The most specific ingredients to the genus Latrodectus are a number of toxins called, appropriately, latrotoxins. Latrotoxins are very large molecules with dozens of different atoms, and the way they work is still not well understood. Black Widow venom contains at least seven different latrotoxins (most of which specifically effect invertebrates, or insects, which form the bulk of the spider's diet). There is one, however, called alpha-latrotoxin, which targets vertebrates—including humans. This powerful poison is specific to the genus Latrodectus and is the reason the spider is so toxic to humans.

Tools for Getting Rid of Black Widows

Tool
Average Price
Bug Vacuum
$13
Window Sealant
$6
Zenprox Aerosol
$20
Stryker 54 Contact Spray
$30

12. How to Get Rid of Black Widows

It can be difficult to manage black widows in your home, especially since they are so good at hiding. However, if you take certain precautions, you will be far less likely to get bitten.

Ways to Avoid Black Widow Bites

  • Keep beds away from the walls.
  • Don't store boxes or any items under your bed.
  • Keep dust ruffles or bed skirts from touching the floor.
  • Don't store shoes on the floor or any clothes, towels or other linens (always shake out shoes and clothes before using).
  • Store sports equipment like rollerskates, gardening clothes, gloves, ski boots in plastic bags that are tightly sealed with no holes.
  • Vacuum under furniture, closets, under heaters, around all baseboards and other areas of the house to eliminate habitat.
  • Keep screens on windows and fix or replace screens with holes or that don't fit snuggly.
  • Seal doors with weather stripping and door sweeps.
  • Seal cracks, access holes for electrical conduits or plumbing.
  • Remove spider webs and egg sags when found.

Other Bugs That Get Into Your House

Insect
Description
Centipedes
Arthropods belonging to the class Chilopoda of the subphylum Myriapoda, an arthropod group which also includes Millipedes and other multi-legged creatures.
Silverfish
A silverfish is a small, wingless insect.
Ants
Social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the Cretaceous period.

Questions & Answers

    Seen Any Black Widows Lately? Leave a Comment!

      0 of 8192 characters used
      Post Comment

      • profile image

        Brendan Asmussen 

        5 months ago

        Well it's all quite amusing really to think that the spider and her crew can actually eat the Male,there is cases we have studied the in a odd ocasion the Male will turn and the hunter becomes the hunted.Just a little food for thought yummy

      • promisem profile image

        Scott S Bateman 

        3 years ago

        The headline for this article caught my attention because I have heard several times that black widows have been spotted in my neighborhood.

        I haven't found one yet, but I'm concerned because I spend a lot of time in our basement and backyard.

        Your article will make me more observant going forward. I also have to say that it is exceptionally thorough, visual and informative. Nicely done.

      • profile image

        RANADEEP 

        5 years ago

        I think it is scary though,but it will not bite unless it feels insecure!!A very good lense in this topic!!

      • BarbRad profile image

        Barbara Radisavljevic 

        5 years ago from Templeton, CA

        I followed an image I thought might be an American House spider here from Google, and it turned out to be your male black widow. I'm quite sure it's not the one hanging over my shower and in the corners of the ceilings all over the house. I believe they are umbrella spiders, but I can't find this as a scientific or even common name when I search for them online. Anyway, that's how I wound up here. Excellent lens.

      • profile image

        anonymous 

        5 years ago

        I saw one in my home last week and I'm terrified, I hate spiders or any kind of bugs, and I'm super scared right now

        The spider is in this spot of my house that I can't reach, what can I do?

      • profile image

        anonymous 

        6 years ago

        Oh, these are scary insects, glad we don't have any around, well...except for some people's pets. :)

      • profile image

        anonymous 

        6 years ago

        Found one in my baggie of grapes this morning.....that was a delightful start to my Monday morning!!!

      • profile image

        sherioz 

        6 years ago

        Luckily I've never met a dangerous spider in person. These are gorgeous spiders and I hope I never see them off the printed page or computer screen. Blessed.

      • profile image

        anonymous 

        6 years ago

        I live in Marietta Ga and my back yard seems to be infested with black widows. We saw 2 yesterday. We had a dumpster of dirt delivered about a month age and my kids played in it till it became some compacted. As we were picking up small rocks for an art project my son flipped over a med size rock and there it was. I tried to kill it with a shoe, but when I missed it began running and got away. He then flipped over a small rock and there was another one, Now my back yard is considered a danger zone. Should I put sticky pads all over the yard or is there a spray/power or something that will make them get, go or die. I know they are good for bug control, but I have babies walking around my back yard.- HELP!! fyi-normal, I'm not scared of them because they are not aggressive, its the quantity that concerns me.

      • KandDMarketing profile image

        KandDMarketing 

        6 years ago

        Black Widows and Brown Recluse are both relatively common in and around the Ozarks region of southern Missouri and Northern Arkansas. You just need to be aware of them.

      • tfsherman lm profile image

        tfsherman lm 

        6 years ago

        Gorgeous web! I'm very fond of spiders -- not black widows though.

      • UKGhostwriter profile image

        UKGhostwriter 

        6 years ago

        Never seen a live one ..even a tiny money spider can cause havoc in my family

      • gottaloveit2 profile image

        gottaloveit2 

        6 years ago

        I hate spiders, period! And, with a house that's 160 years old, I can't get away from them. Spider spray is my best friend.

      • junecampbell profile image

        June Campbell 

        6 years ago from North Vancouver, BC, Canada

        I have never seen one. I am happy to leave it that way.

      • profile image

        JoshK47 

        6 years ago

        Positively wonderfully presented information here - thankfully, I've not seen any around here! Blessed by a SquidAngel!

      • KathyBatesel profile image

        KathyBatesel 

        6 years ago

        As a kid, I used to go on weekly widow hunts with Raid. My house literally had dozens of them around our hose faucets, in my father's workbench areas and our storage unit every time I did! As I got older and didn't play outside as much, I stopped. In high school, I awoke with a weird little pimple-like nodule on my thigh. I popped it, but by my second class of the day it had gotten huge - larger than a coffee cup saucer and HOT to touch. The school nurse said it was probably a black widow bite, which aren't all that rare in Arizona. When I got home, I went to find where it might have come from inside my house, and I discovered several webs and adolescent spiders on the sides of our sofa. I believe that was an adolescent bite, though some sources say the young are harmless.

        Some years later, I was sitting on a pipe ell at my school and was bit on the foot. This time, I saw the spider. Again, lots of swelling and hot to the touch, but those are the only symptoms I got either time.

      • laughingapple profile image

        laughingapple 

        6 years ago

        Excellent lens. I have run into these spiders a few times in the wild. They look beautiful but of course are best appreciated from afar(or in photos).

      • profile image

        anonymous 

        6 years ago

        I haven't and hope to keep it that way. What an amazingly informative lens. Well done.

      • LiteraryMind profile image

        Ellen Gregory 

        6 years ago from Connecticut, USA

        I saw one about 7 years ago crawling on the side of my house near the bulk head door. I killed it. I was afraid it might multiply and get into my crawl space.

      • iWriteaLot profile image

        iWriteaLot 

        6 years ago

        What a creepy lens! But very informative. To think that a bit that tiny could do so much damage. But it's good to know that they only bite if you go after them. *shivers*! Blessed.... at a distance! LOL

      • Joan Haines profile image

        Joan Haines 

        6 years ago

        "Squid Angel blessed."

      • Joan Haines profile image

        Joan Haines 

        6 years ago

        When I was nine, our house was overrun with black widows. True story.

      working

      This website uses cookies

      As a user in the EEA, your approval is needed on a few things. To provide a better website experience, owlcation.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

      For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://owlcation.com/privacy-policy#gdpr

      Show Details
      Necessary
      HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
      LoginThis is necessary to sign in to the HubPages Service.
      Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
      AkismetThis is used to detect comment spam. (Privacy Policy)
      HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
      HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
      Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
      CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
      Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
      Features
      Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
      Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
      Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
      Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
      Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
      VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
      PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
      Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
      MavenThis supports the Maven widget and search functionality. (Privacy Policy)
      Marketing
      Google AdSenseThis is an ad network. (Privacy Policy)
      Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
      Index ExchangeThis is an ad network. (Privacy Policy)
      SovrnThis is an ad network. (Privacy Policy)
      Facebook AdsThis is an ad network. (Privacy Policy)
      Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
      AppNexusThis is an ad network. (Privacy Policy)
      OpenxThis is an ad network. (Privacy Policy)
      Rubicon ProjectThis is an ad network. (Privacy Policy)
      TripleLiftThis is an ad network. (Privacy Policy)
      Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
      Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
      Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
      Statistics
      Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
      ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
      Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)