Black Widow Spider: All You Need to Know for Safety and Curiosity

Black widow spiders are found throughout North America, with a high concentration in the southern and western regions of the United States.

These arachnids are notorious for their potent venom and distinctive red markings on the underside of their abdomen, making them easily recognizable.

These spiders are part of the larger cobweb spider family, characterized by their web-making abilities.

The female black widow, which is considered dangerous, can bite and inject toxic venom. It’s essential to know about these spiders to stay safe and avoid any potential harm.

There are several other spiders commonly found in the United States, such as the brown recluse and tarantula.

A comparison between these spiders and the black widow can help people distinguish between them and ensure their safety around these creatures.

Black Widow Spider Overview

Identification and Appearance

• Female: Shiny and jet black
• Male: Black with white underbody
• Markings: Red hourglass shape on the underside of the abdomen
• Eyes: Eight eyes, arranged in two rows of four. Their vision is poor.
• Size: 8-13mm in body length, 25-35mm with legs extended ¹

The southern black widow spider has distinct markings which make identification easier.

Below is a comparison table of the characteristics of the female and male black widow spiders.

Characteristic	Female	Male
Color	Jet black	Black with white underbody
Markings	Red hourglass on the abdomen	None
Size (Body length)	8-13mm	Smaller than females

Habitat and Distribution

Black widow spiders, specifically the southern black widow (Latrodectus mactans), are found across the United States.

They prefer warm, dark, and dry places, such as woodpiles, garages, and sheds.

Diet

Black widow spiders are carnivorous predators that primarily feed on a variety of insects and other arthropods. Their diet includes:

1. Flies: They often catch and consume various species of flies that get trapped in their webs.
2. Mosquitoes: These are another common prey for black widows.
3. Grasshoppers: Larger black widows can subdue and eat grasshoppers.
4. Beetles: Various types of beetles can become prey for these spiders.
5. Caterpillars: Some black widows may catch caterpillars in their webs.
6. Other spiders: Black widows are known to be cannibalistic, especially after mating. The female often eats the male, which is how the spider got its name. They can also eat other spiders that venture into their territory.

Hunting Strategy

Black widows use their webs to trap their prey.

Once an insect is caught in the web, the black widow quickly moves to it, and bites it to inject its venom, which immobilizes and begins to digest the prey.

After the venom has taken effect, the spider wraps the prey in silk and consumes it by injecting digestive enzymes and then ingesting the liquefied remains.

Are Black Widow Spiders Dangerous For Humans?

Yes, black widow spiders can be dangerous to humans, but it’s important to put the risk in perspective.

Treatment of Bites

If someone is bitten by a black widow spider, it’s essential to seek medical attention promptly.

While antivenom exists, it’s rarely used in the U.S. due to potential side effects.

Instead, treatment typically focuses on managing symptoms. Pain relief, muscle relaxants, and supportive care are the mainstays of treatment.

Prevention and Safety Measures

Reducing Encounters

To reduce encounters with black widow spiders, it’s essential to keep your surroundings clean and clutter-free. For instance:

• Remove piles of wood, debris, and garbage from your yard or garage
• Regularly check for any webs or signs of spiders and safely remove them

By eliminating potential hiding places, you can decrease the chances of coming in contact with these venomous creatures.

Protective Gear

Wearing protective gear is an effective way to prevent black widow spider bites. Some examples include:

• Gloves: Always wear gloves while working in areas where spiders may be present, such as gardening or moving objects in a garage
• Long sleeves and pants: Cover your skin to minimize exposure to bites

Precautions

In case a black widow spider bite does occur, there are some precautions you can take to minimize the effects:

• Apply an ice pack to the area to reduce swelling and numb the pain
• Seek prompt medical attention for proper treatment

Comparison Table: Black Widow Spider vs Rattlesnake

Feature	Black Widow Spider	Rattlesnake
Type of Venom	Neurotoxin	Hemotoxin
Main Symptoms of a Bite	Severe pain, muscle cramps, nausea	Swelling, severe pain, difficulty breathing
Key Female Characteristic	Red hourglass shape on the abdomen	Females larger, no distinct markings

Remember, the key to prevention is vigilance and maintaining clean environments to reduce encounters with venomous species.

Black Widows in Pop Culture

Marvel’s Black Widow

The Black Widow is a popular character in Marvel’s comics and movies.

She is a member of the Avengers and has been portrayed in various forms across media.

Natasha Romanoff, also known as Black Widow, is a skilled spy, fighter, and strategist.

• Avengers: Black Widow is an integral member of this superhero team.
• Natasha Romanoff: The character’s real name and alter ego.
• Marvel: Black Widow’s creator and publisher.

Black Widow’s popularity in the Marvel movies led to her own standalone film, which delves into her past and her journey to becoming a superhero.

Characteristic	Black Widow
Real Name	Natasha Romanoff
Team Affiliation	Avengers
Publisher	Marvel
Powers & Abilities	Skilled fighter, marksman, and spy

In the Marvel Cinematic Universe, Natasha has been a key figure in various films, such as The Avengers, Captain America: The Winter Soldier, and Avengers: Age of Ultron, where she showcases her skills and relationships with other superheroes.

Conclusion

Footnotes

1. Southern Black Widow Spider ↩

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about black widow spiders. Scroll down to have a look at some of them.

Letter 1 – Australian Redback Spider (Australian Widow) eats Lizard!!!

Impressive
Dear WTB,
I came upon your site today, it’s an amazing archive. I thought that these two pictures would be of interest to you.

Obviously they are not the best spider photos, but at the time I was more impressed with the size of its meal. The lizard is approx 3″ long and the spider is an Australian Red Back.
Regards
Simon
Coffs Harbour, Australia

Hi Simon,
Impressive sure is an apt description. The Australian Redback Spider, Latrodectus hasselti, is in the same genus as the American Black Widow, and the venom of the female is also quite toxic. Here is a site with more information.

Letter 2 – Black Widow

Marlos-
It’s Katey, from class last summer. (Remember me? I’ve seen almost all the movies?) Anyway, I just moved to Highland Park and I’m finding black widows everywhere.

Here are two pictures I took, they aren’t very good but I have a phobia of spiders and that’s the best I could do without passing out. They hang upside down in their web, very creepy.

I’m positive they are black widows because I sprayed them (a lot!) and eventually they bellied up and I saw the hour glass. I tried to get a picture of that but my camera isn’t good enough (and I was still scared to get close).
See you at Art Center, have a nice break.
Katey Bright

Hi Katey,
Glad you are well. You can recognize Black Widows by their unique silhouette, which is evident in your photos. I let the Black Widows live where they want to in my Mt. Washington house.

They build webs and stay in the webs. They are very shy, nocturnal and not aggressive. As long as you know where they are living, you can avoid them. Thanks for the photos and I’m glad you are well. Did you change your major?

Letter 3 – Black Widow

Black widow picture + “bee” question
Hello,
A friend told me about your site – it’s great!! I’ve been reading with a mixture of the creeps and fascination. Thank you for the informative site and terrific pictures.

Speaking of pictures, attached is one of a black widow if you’d like more for your collection. We found this one on our outdoor grill (hence the “ Kenmore” logo) – much bigger than we had expected.

I also have a question – unfortunately no picture since we have moved recently. At our old house in San Jose , we used to have “bees” visiting our flowers – except these were so big and lumbering we called them “Bee-52s.” Their bodies were huge and shiny black (guessing an inch long?).

They were so large their buzz sounded amplified and when they landed on flowers the whole limb would sag down. They seemed to be solitary – if another one came along they’d lumber over and chase them. Was this a bee and if so what kind? It was definitely interested in flowers (it loved the ones on our potato bush).
Thanks very much!
Jennifer

Hi Jennifer,
Thanks for the Black Widow Photo and also your kind letter. We believe your bee is a female Carpenter Bee.

Letter 4 – Black Widow

Spider
Though I would send you a good picture of a BLACK WIDOW spider. The longest legs are 1 3/8″ each .

What a Beauty.

Letter 5 – Black Widow

American Homebody, our mother site, just sent in this photo of a female Black Widow spider spotted in their Jefferson Park offices.

(01/31/2004) Not True but False Widow

Hi,
Great site!
Have a question about black widows. When we lived in the New Orleans area, we saw several spiders that were black and shaped just like a black widow, but had red markings on the top side of the abdomen.

I have not been able to find anything online that resembles them , and thought you might be able to help.
Thanks,
Mary P

Hi Mary,
First, the red hourglass is on the under side of the abdomen. There is a spider known as the False Widow, Steatoda grossa. Both the true and false widows belong to the Comb Footed Spider Family Theridiidae.

The False Widow is a beneficial spider, reported to prey on its more poisonous relative. It also eats Sow Bugs. It is a hardier spider than the true Black Widow. We find them in our yard all the time, and will take a photo the next time.

Letter 6 – Black Widow

I have a juvenile Southern Black Widow in a jar at my house. She’s very small and has striped legs, a red stripe down the topside of her abdomen and of course, the tell tale hourglass on the underside of her abdomen. I’ve had her now for approximately 3 weeks.

I would very much like to keep her but since I have a 10 year old daughter I cannot just let her roam about freely. I don’t want to put her outside because I live in Oklahoma and the temperature is decreasing daily. The jar that I have her in is a gallon glass jar with a metal lid. We’ve poked holes in the lid so she can breathe and put dirt, rocks, leaves and plenty of sticks in the jar.

She seems to be content because she has spun a very nice web in there. We’ve fed her a variety of things including flies, little bees and other spiders. She liked all of those just fine but now that the weather is turning much colder it is getting harder to find suitable bugs for her. So, I went to the pet store and bought her some crickets.

There is only one problem, the crickets are much bigger than she is and she won’t eat them! Last night she was hanging upside down in her web as she always does and one of the crickets walked right up to her (via a stick) and she retreated. The cricket then stomped all over her web and went back to the bottom of the jar. I have a few questions concerning this amazing spider of mine.

• First of all, will she eat the cricket if she’s hungry or is he just too big for her?
• Will the cricket eat her?
• How often do Black Widows need to eat?
• Does she need a fresh supply of water or does she get this from her prey?
• If she does need a fresh supply of water, how much?
• When will she molt?
• When she does, how long afterwards should I wait to feed her again?

I very much adore this spider and want her to live through the winter. Please let me know what I can do to keep this truly wonderful creature alive and well. Thank you!
Misty McClain

Dear Misty,
Thank you for your sensitive letter. I will try to answer all your questions. First, while it is possible for your juvenile spider to feed off of the crickets, the size differential might be a problem. Find out from your pet store what their source of crickets is.

You might be able to contact the breeder and get juvenile crickets. Another solution which might be fun for your daughter as well is to raise Drosophila, fruit flies, which can be obtained from a biological supply house for schools, or you can just try to attract the flies to an overripe banana in your kitchen.

The fruit flies are very easy to raise as any home maker who has forgotten to remove fruit from the kitchen or fogotten to take the garbage to the compost pile. I always have some fruit flies swarming in my kitchen.

Crickets are omniverous, and they might try to eat your spider. Not to be evasive, but your spider will eat when hungry. In the wild, they do not eat daily, but rather when they catch prey.

Sometimes this happens several times a day, and at other times it might be weeks between meals. The spiders are resilient. Black Widows are fond of damp dark places but they will not drink water. They get their water from the life giving juices sucked out of their prey.

She will molt when she has outgrown her current skin. This happens several times over the course of her life. At her final moult she will achieve the glossy black color that typifies her species. it is also possible that you have a male spider which is colored similarly to the juvenile. I hope this answers your questions, and good luck.

Letter 7 – Black Widow

Dear Daniel,
I’m sorry to report that my captive black widow has apparently expired, without warning, and before her time (I think), and I’m hoping that you might be able to offer some possible causes of death.

I found this brave arachnid in my house, right next to the front door, where she had constructed a nice web in the corner. This was surprising, because these spiders are typically shy-er and aviod the insides of our home, keeping to the piles of garbage and debris that surround it.

I dusted off my spider cage and tossed her in with some sticks, and she set up shop immediately, dispatching every bug I could capture and introduce into her one-spider ecosystem. She ate four flies in about three weeks, and then, last night I caught three June beetles almost at once and decied to toss them all in and see how she’d handle an overabundance of supplies.

She caught and wrapped all three in quick succession, then set to work on one, and I went to bed. This morning she was curled up in a ball on the bottom of the cage (see photo). Now there’s a giant bead of clear fluid emerging from her mouth-parts-area, and her legs are sort of clenching up and slowly releasing, over and over.

Could all this be the result of a tainted june beetle? Is she going to suddenly pop out of her old exoskeleton and finish off the three meals left un-eaten in her web? Please advise.
Yours,
Sean Dungan

Dear Sean,
I have never heard of a spider stuffing herself to death, but I guess that is always a possibility.

I guess you should just wait and see what happens. Her typical lifespan would be three years, and it is entirely possible that you had a senior citizen move in with you.

Letter 8 – Black Widow

Friends;
It’s summertime in the Canyon, so that means it’s bugtime. I killed a number of these over the holiday weekend, but thought I’d take a picture of this lady before I smushed her with a broom.

I would’ve tried to get in closer, but admittedly, I was a little scared.
Chris

Hi Chris,
Thanks for the update on the buggy canyon. Just two days ago I overturned an old piece of wood while planting an oak seedling, and lo and behold, there was a big fat black widow snuggled in a crack on the underside.

I gingerly replaced the wood. I have heard it said that there isn’t a house in southern California that isn’t home to at least 15 black widows, despite the actions of paranoid home owners and the attempts of exterminators to eradicate the species from the planet.

Though she is a desert creature, the Western Black Widow Spider, Latrodectus hesperus, seeks out dark, cool, and usually damp locations to spin her indefinite web. Look for her in wood piles, hollow stumps, crawlspaces and among refuse stored in garages and attics.

The water heater area is often a favorite site. The sexes exhibit pronounced dimorphism, looking like two entirely different species. The male is small and greyish while the much larger female is usually a glossy black, with a red (though sometimes orange or even yellow) hourglass marking beneath her bulbous shiny abdomen.

The size difference contributes to her reputation as a man eater. The bite of both sexes is poisonous, and the venom is reported to be 15 times as strong as that of a rattle snake. Though they are not aggressive, preferring to hide in the dark, they occasionally bite people. Avoid contact with the spider and immediately call a physician if a bite occurs. An ice bag should be placed on the wound and the victim should be kept calm.

Letter 9 – Black Widow

Subject:  Black Widow Spiders
Geographic location of the bug:  Northern New Mexico
Date: 10/04/2017
Time: 12:05 AM EDT
Good evening.
I moved to Santa Fe from Southern Oregon four months ago for work and I have never encountered female black widow spiders like this. We have killed eight large, female specimens in the house over the past two days.  Most of them were on the move in broad daylight, and surprisingly aggressive. 

Two of them were actively sharing a web.  I captured one in my bathroom, and confirmed the red hour glass. I’ve never known female widows to act like this, unless defending egg sacks. Is this a sub species native to New Mexico, or some sort of infestation I was previously unaware of?
How you want your letter signed:  Alexa Rense

Dear Alexa,
According to BugGuide:  “The Latrodectus genus breaks down taxonomically into approximately 31 recognized species, five (5) of which are found in the United States; four (4) species are native, one (1) species (L. geometricus) was introduced.”  According to BugGuide data, it is the Western Black Widow that is found in both Oregon and New Mexico. 

While the bite of a Western Black Widow can be dangerous, they are not an aggressive species, though many female spiders will defend eggs and young.  We are lamenting the loss of native Western Black Widows in Los Angeles where they seem to have been entirely replaced in recent years by the invasive Brown Widow.

Letter 10 – Black Widow Cannibalism and potential undocumented Bug Love

Spider Trapping a Baby Black Widow
Location: Southern California
November 4, 2010 1:10 pm
We found this spider in our backyard on the patio trapping a baby black widow. We are thinking it is either a male black widow or a brown widow, but are uncertain.

We live in Southern California in the Murrieta/Temecula area. We would love to find out what it is. Thanks!
Signature: Courtney

Hi Courtney,
We are intrigued with your photos of Black Widow cannibalism.  The predator in this photo is an immature female Black Widow that will eventually lose that striped pattern and become a glossy black spider, and the prey is exhibiting the telltale red hourglass of a Black Widow as well.

Thank you so much.  Is Black Widow cannibalism common?  Do all females change like this?  Would it have started out all black like the baby here? I understand if you can’t answer all my questions, but I thought I’d try.
Thanks,
Courtney

Hi Courtney,
We were going to paste the third of your photos into this response so we could better determine the identity of the victim.  We have never seen data on the frequency of Black Widow cannibalism, but the name and alleged reason may be an indication that there is fact in the lore. 

With that said, this may be a virgin adolescent female who is still wearing her prepubescent markings.  That may be a suitor that sacrificed his life for the perpetuation of the species. 

Black Widows may be able to mate as adolescents and then storing the spermatozoa until it is needed.  Adult females are glossy black and we have not seen documentation of mature females marked otherwise.

Letter 11 – Black Widow Foreplay

black widow?
Hello, we live in Kentucky and found these in our trash bin outside, we assumed the large one was a black widow, but there is a very small one with it on the side, is that a male or another female?Thanks.
Kerry

Hi Kerry,
Though your photo doesn’t actually show mating activity, we still felt it appropriate for our Love Among the Bugs page. The Black Widow has earned her name because of her reputation for devouring her mate.

The tiny male in the upper corner of your photo is biding his time, living in close proximity and waiting to make his move. The male is a much smaller spider. When the time is right, he will move in and if the fates allow, consumate the pairing.

Once years ago, I watched a male widow snare his mate by spinning a web around her. This probably kept her still while he did the deed, hopefully allowing him to skulk off into the night afterwards.

Update: (08/31/2008)
Bug Love and the Black Widow.
I just had speak up after seeing this section in bug love.. the problem is MALE black widow’s arnt Black and they have no hourglass shape mark on the abdomin. The are actuly almost translusent.

Very small in comparison the the female they are an beige almost. kinda clear looking. Just thought id mention it considering you refer to the other black spider in the picture as a Male… Great site and keep up the good work.
Steve

Hi Steve,
WHile what you say is often true, one has only to glance at page after page of Widow photos on BugGuide to see there are several species and much variability within the species, and much confusion on how to accurately distinguish the various species.

We searched until we found some support that male Widow Spiders can have an hourglass. There is a series of three images of a very black male spider with red marking on the upper surface as well as a distinct hourglass underneath that are posted to BugGuide. Lee from Cass County, Texas, questioned the hourglass specifically.

The identification on that spider is the Southern Black Widow, Latrodectus mactans. BugGuide has not received any submissions of the Southern Widow from Kentucky, where the photo in question was taken, but submissions from Ohio and Illinois would indicate that the Southern Widow ranges far enough north to include Kentucky.

Our conclusion that the spider in the photo submitted to our site was a male was based on behavior, that the diminutive male Widow Spider will take up position at the perifery of the larger female’s web until he can attempt mating.

Letter 12 – Black Widow Mating

Blackwidow Love
Thought you might enjoy. This gal hung out on the window for months and then this little dude showed up – I though she would eat him right away but after 2 weeks I looked him up on the internet. He is her male counterpart, funny I thought he would look like her. Anyway they finally got to business many many times. I took tons of shots of them and then, a day latter, he was lunch.
Robin

Hi Robin,
Thanks for sending your awesome documentation of the mating of a Black Widow. Black Widows are sexually dimorphic, meaning the sexes do not look alike.

Letter 13 – Black Widow: Not quite Mature and a Mouse Spider

Black Widow? Strange Mark?
Hi Bugman,
I enjoy your site daily. We were cleaning out our Garage today and ran into this spider under some cardboard boxes. I assume it’s a Black Widow, but didn’t see any red on her. What I found interesting was the mark she has on her body. I thought it might just be a scratch of some sort, but was curious to see what you made of it.

I can send you a larger picture if you want to zoom in more. I am located in Woodland Hills, California. I sent while you have been having trouble getting pictures and then I was looking at the site today and read the one part about the person posting the picture incase you didn’t get it in the email… And I thought “Why didn’t I think of that!”
Here is a link to the below spider I mentioned: Thanks so much,
Angela

Also if you might have the time, we have this spider very often in our house and we are always ushering them outside. I think it might be a wolf spider, but I can’t quite seem to find a wolf spider that looks like this one on your site? Thank you so much! I have your site as my default page because I love checking it everyday!

Hi Angela,
That works nicely for us. We hope to have our email attachments straightened out soon. This is a Widow. Immature females are gaily colored spiders with cream and red markings on their backs. As the spiders mature and molt, they loose the colors and eventually become glossy black.

Your spider is nearing maturity. Your other spider is one that Charles Hogue, in his fabulous book Insects of the Los Angeles Basin, identifies as a Mouse Spider, Scotophaeus blackwalli.

It is a European immigrant often found in homes where it hunts and does not build webs. While searching for online substantiation, we located a Frequently Encounted Spiders in California website that substantiates this identification.

Letter 14 – Black Widow Photos

Oh! and speaking of monsters… I’ve attached a few pictures of a black widow I found crawling up my leg as I studied….=) Also set that one free…

I really should have thought about my downstairs neighbors before chucking it out my 4th story window… I also had a bad termite problem in that apartment… but those pictures are just plain gross. I’ve sinced moved into a new apartment… So far… no bugs…
Thanks again!
Leah

Thank you for the Black Widow photos Leah. You are a brave girl.

Letter 15 – Black Widow released in the woods

Subject: Black Widow
Location: Ashburn, VA
December 17, 2012 1:40 pm
We had a little visitor to our apartment just before Halloween. I meant to send you these pics then, but life got in the way. Even though I am extremely arachnophobic (sp?), I did capture and then release this miniature monster in our nearby woods. Enjoy the pictures!
Signature: Amber

Hi Amber,
Because of your sensitive treatment of this healthy looking, female Black Widow, we are tagging your posting with the Bug Humanitarian Award, a distinction we reserve for folks who go out of their way to show respect for the lower beasts.

Letter 16 – Black Widow sighted during Eclipse

Subject: Is this a Black Widow Spider
Location: Johnstown, PA
August 21, 2017 2:53 pm
My name is John and I am the safety director for a company based out of Johnstown, PA. Earlier today, August 21, 2017 I was approached by two mechanics working on a truck with a concern over a spider. Today was the day of the eclipse and was a very nice warm day, temperature mid to upper 80’s.

the spider was located in a sealed portion of the truck that under normal circumstances is very dark. there was a repair needed in the area so a hatch was opened up to reveal the webbing and the spider. After multiple people viewed the spider there was an ensuing debate on whether it was a Black Widow or not. Please help.
Signature: John Gregorchik

Dear John,
Because of the red hourglass marking on the ventral surface, we are 100% confident this is a female Black Widow Spider.