Black Widow Spider Habitat

Black Widow Spider Habitat. The neurotoxic venom (a poison that affects nerve cells) of the Black Widow spider (Latrodectus spp.) is well-known.

The Black Widow Spider, which may be found in both urban and agricultural settings, is a large widow spider that can be found across the globe.

The three North American species with the darkest coloration, black hair, and crimson hourglass pattern are referred to as the “black widow spiders.”

The Australian red-back, brown widow spider (sometimes known as the grey widow) and the red widow spider are among the 31 recognized species in the Latrodectus (widow spider) genus. Widow spiders are also known as the “button spiders” in South Africa.

The southern black widow (Latrodectus mactans), northern black widow (Latrodectus variolus), and western black widow (Latrodectus hesperus) are the three North American species of black widows that are currently recognized.


Temperate spiders, such as North America, southern Europe, and Asia, Australia, Africa, and much of South America are all found in the Latrodectus genus.

According to the St. Lucie County, Florida, black widows prefer urban environments as well as woodlands, deserts, and grasslands across the United States. (opens in a new tab) Louis Zoo

According to North Carolina State University (opens in new tab), widows frequently build their webs near where people dwell, often in dark corners inside or outside of buildings.


Black widows, like most spiders, hunt for food and favourable conditions. During the day, they stay hidden in nooks, then emerge at night to hunt. This happens most of the time outside of your home, but they may sometimes come in.

They search out obscurely lighted, protected places to spin their webs, hoping to catch grasshoppers, mosquitoes, caterpillars, beetles and other varieties of prey. Because most homes don’t have a lot of bugs, black widow populations will be low.


Black Widow spiders favour dark, quiet places to build their webs. Nest sites are often found near small animal holes, building openings, and wood piles. Black widow spiders may be found in low-growing shrubs as well.

Black widow spider webs may be found around woodpiles, debris, hollow logs, loose bark, holes, stones, burrows, small trees, bushes, drainage pipes and root cellars.


Black widow spiders can be found in dark, undisturbed areas such as behind furniture or beneath desks when they are indoors. Widow spiders also utilize undisturbed basement areas and crawl spaces in homes.

Cardboard boxes, seldom-used shoes, sheds, barns, garages, attics, pipe holes, doors, air vents, basements, crawl spaces, false ceilings and storage spaces are just a few of the places to check.

The Latrodectus genus includes black widows. There are roughly 30 different types of black widows within this genus.

The Southern widow (L. conspersa) is the only one that may be found in the United States. Northern widow (L. mactans), for example The Western widow (L. variolus) is another kind of widow. (The sphinx is called Hesperus.)

These black widows are distributed around the United States, as their names imply.

The concentration of Southern black widows is greatest in the Southeast, although they may be found as far north as New York and west as Arizona.

Northern widows prefer New England and Southeastern Canada, however have been discovered as far west as Texas and as far south as Florida. Web builders prefer to build their webs in tree limbs.

In addition to the typical black widow spider habitats described above, the Western black widow may build its web in arid deserts or high mountains. While it has been recorded as far north as Southwestern Canada, this species is mostly found in Texas, Mexico, Oklahoma, Kansas, and the Pacific Coast states.

Of course, not all spiders are dangerous. If pests are preventing you from doing your job, however, contact Terminix®.

In loose stone or wood piles, in corners of rooms, garages, and outbuildings, Black Widow spiders create loose and uneven mesh-type webs on plants. They don’t weave the funnel pattern web seen in funnel weaver spiders (Agelenidae) or the symmetrical web seen in orb weaving spiders (Araneidae).


These spiders are not particularly tiny, despite their venom being extremely powerful (15 times more powerful than that of rattlesnakes, but only a little bit more powerful than the venom of cobras and coral snakes).

Even though it sometimes feels like you’ve been stung, spiders bite but don’t sting. Their chelicerae aren’t particularly huge or strong when compared to those of many other spiders.

The hollow, needle-shaped section of each chelicera, which pierces the skin and injects the venom to a dangerous depth, is approximately 1.0 millimetres (around 0.04 inch) long in the case of a mature female.

Males have lower venom levels and inject it in a shallower manner since they are smaller. Even when a mature female injects a significant amount, it is virtually insignificant in terms of physical volume.

Although it may cause the very unpleasant symptoms of latrodectism (the clinical syndrome induced by the neurotoxic venom), when this small quantity of venom is spread throughout a healthy, adult human’s body, it seldom amounts to a lethal dosage.

In terms of the number of black widow spider bites per thousand people, deaths in healthy adults are relatively uncommon.

Muscle and chest discomfort may result from the bite. Cramps and nausea may accompany the pain, which can spread to the abdomen. Restlessness, Trembling, Sweating, and Difficult Breathing are some of the other common symptoms.

Extremities (hands and feet) and eyelids swell more frequently than the bite site, although it is uncommon. Acute symptoms often rise in intensity on the first day following a bite, and there is often a general feeling of unease shortly after the bite.

Although most symptoms disappear after two to three days, some may persist for many weeks following recovery.


The common name “widow spiders” has been coined to describe the prevalence of sexual cannibalism, in which a female consumes a male following mating. The offspring’s survival odds may be improved by this behavior.

Females of some species, on the other hand, rarely engage in this behavior, and most of the verified evidence for sexual cannibalism has been gathered in laboratory cages with males unable to flee.

To avoid being consumed themselves, male black widow spiders pick their mates based on whether the female has eaten. The chemicals in the web are able to indicate if the female has received food.

Since it will resort to cannibalism in desperate situations, Latrodectus hesperus is known as an “opportunistic cannibal.” Latrodectus hesperus is also known to cannibalize siblings in addition to sexual cannibalism.

Widow spiders build an irregular, knotted, sticky silken web similar to other Theridiidae members. In dark and undisturbed places, black widow spiders prefer to build near the ground, often in little holes excavated by creatures or around building entrances or woodpiles.

Indoor nests are often found in basements or other dark, quiet areas beneath desks or furniture. The spider sits waiting for insects to blunder into its web and get stuck, often hanging upside down near the center.

The spider rushes over to envenomate and wrap the insect in silk before it can extricate itself. The spider’s mouth pulses digestive fluids over the meal, which liquifies and is drawn into the spider’s mouth by capillary action.

Little flies, mosquitoes, grasshoppers, beetles, and caterpillars are among the insects they consume. The spider lowers itself to the ground on a silk safety line as soon as it detects a danger.

These spiders have extremely poor vision and rely on vibrations reaching them via their webs to locate trapped prey or alert them of bigger dangers, similar to other web-weavers. Widow spiders are unlikely to bite when they are caught; instead, they play dead or flick silk at approaching danger, which causes bites.

When a spider is squeezed or pinched inadvertently, it delivers defensive bites to humans, which cause numerous injuries. The primary predator of black widow spiders in western North America is the blue mud dauber species, Chalybion californicum.

The physical characteristics of Latrodectus hesperus (western black widow) silk are comparable to those of silk from orb-weaving spiders that have previously been investigated in other research. In the Blackledge study, each of the three types of silk had a tensile strength of about 1,000 MPa.

Trichonephila edulis had a maximal strength of 1,290 ± 160 MPa, according to a previous study. Spider silk has a tensile strength comparable to that of steel wire of the same thickness, but since steel is about six times as heavy as silk, it is much stronger. [failed verification]

Although their bite may be unpleasant, widow spiders (also known as “false widow spiders”) are much less harmful to humans than those in the genus Steatoda (also of the Theridiidae).


Black widow bites may cause systemic symptoms (latrodectism) including severe muscle pain, abdominal cramps, hyperhidrosis, tachycardia, and muscle spasms. They are potentially hazardous due to the presence of latrotoxin in their venom.

The majority of people experience symptoms that last 3–7 days, but they may persist for many weeks. Allan Blair, a member of the University of Alabama Medical School, conducted an experiment on himself in 1933 to demonstrate the symptoms of a black widow bite and to see if someone could develop immunity after being bitten.

Blair failed to complete the experiment and did not want to be bitten a second time because the bite was so painful and harsh.

Around 2,200 individuals in the United States are bitten by a black widow every year, although medical care is rarely required.

Certain bites are “dry” in that the venom isn’t injected. Since 1983, the American Association of Poison Control Centers has not received any fatalities from black widows in the United States. Unless startled or otherwise threatened, black widows are not particularly aggressive spiders and seldom bite humans.

The majority of individuals bitten do not sustain significant injury, much less death. The Mediterranean black widow, Latrodectus tredecimguttatus, was the most common source of fatal bites in the early twentieth century.

Antivenom has been utilized as a source of pain relief rather than as a means to rescue lives since the venom is not typically life-threatening. Nevertheless, according to a research, using antivenom or a placebo along with standardized pain medication resulted in comparable decreases in discomfort and symptom improvement.



The black widow, like other spiders, consumes arthropods and insects that get entangled in their webs. Females, on the other hand, do not usually consume their males, according to the Burke Museum of Natural History and Culture(opens in new tab) in Seattle, Washington.

In the Southern Hemisphere, and most black widow males “survive to mate another day,” according to the museum, only one known Latrodectus species practices mate cannibalism in nature.

According to the Nature Conservancy of Canada (opens in new tab), black widow newborns are known to devour their newly hatched siblings as they emerge from their eggs.

According to the Missouri Department of Conservation, widows eat flying and climbing insects, as well as arachnids and other small vertebrates like snakes and lizards.

The spider paralyzes its meal with a venomous bite once the prey gets tangled up in the black widow’s web. According to the Department of Entomology at Iowa State University(opens in new tab), when the prey stops moving, the spider injects digestive enzymes into the victim’s bloodstream before carrying it away to be devoured.