How do you know if you have a black widow infestation?
All you need to know about black widows, from their physical features to habitat and black widow infestation signs.
Black Widow Infestation Signs
The black widow spider got its name from sexual cannibalism, an irregular phenomenon involving the female and male spider species.
Here, the female spider kills and eats the male counterpart after a violent mating. Nevertheless, this occurs probably when the males are in captivity without a means of getting away.
These arachnids are distinguished by the red hourglass marks on the upper part of their abdomen. This helps to keep predators at bay.
What are the Physical Features of a Black Widow?
While black widows are usually black, the females are sometimes brownish-black. Also, the younger species are orange and white-colored.
However, these arachnids undergo molting as they grow, making them black. These spiders are mostly medium-sized, measuring about 3 to 10mm.
Compared to the short lifespan of males, females can live for 1- 3 years.
The black widow spider matures from an egg into an adult within a year. Like the web weavers, these spiders have poor vision; hence they rely on vibrations for survival.
Where Do Black Widow Spiders Live?
Black widows thrive on all continents except Antarctica. They’re primarily found in firewood piles, under stones, rodent holes, and hollow tree stumps.
They seek out warm areas; thus, you’ll see them in unused blankets, shoes, and crevices.
What Are the Characteristics of Black Widow Spiders?
While black widows are quite active at 70 degrees and above, they can live in lower temperatures under the right conditions.
Like other spider species, black widows spin irregular, tangled webs near ground level at night. They often hang on the webs, waiting for their prey to get trapped in them.
Once trapped, the spiders move swiftly to surround the prey with silk. Black widows feed on their prey by secreting digestive juices, which aid feeding and digestion.
They often feed on small insects like grasshoppers, caterpillars, mosquitoes, beetles, and flies. Females are believed to eat their male counterparts after mating.
This isn’t 100% true, as documented cases occur in confined spaces where the male black widow can’t escape. Most times, the males can distinguish if their mates have eaten by perceiving chemicals on the web.
This works to prevent them from being eaten by the females.
Do Black Widow Spiders Bite?
Black widow spiders rarely bite except when they (especially females) are attacked. The female spider’s bites are quite harmful as its venom is 15 times more poisonous than a rattlesnake.
When humans are bitten, they develop muscle aches, paralysis, and nausea. Other symptoms include fever, high blood pressure, difficulty breathing, etc.
These bites seldom lead to death but can be dangerous to kids, the sick, and the elderly. There are rarely fatalities once proper care is administered.
Typically, the pain gradually begins when bitten and reaches its climax within 3 hours. By then, the bite has developed into a lesion.
To know if a black widow has bitten you, check for two faint puncture wounds around the bite region. If inflammation occurs after being bitten, you may not likely see bite marks.
Administering antivenin injection to patients can boost recovery from the bites. Pain killers, muscle relaxants, and other medications help lower the blood pressure associated with the bite.
A secondary infection may occur if the bite isn’t properly checked.
You should clean the bite site with soap, apply a cold compress on the affected area for 10 minutes, and localize the bite so the venom doesn’t spread to other parts of the body.
What are the signs of black widow infestation?
If there’s a black widow spider in your living space, here are signs that your home has been infested.
Black Widow Spider Web
Typically, black widow spider webs are irregular, looking like it’s formed within some minutes. Unlike other spider species, black widows don’t spin their webs on elevated locations.
The webs work for hunting and as means of defense against predators. A black widow spider web consists of 3 layers: the top, middle and bottom layers. Each layer has its functions.
The top layer weaves the strongest threads, protecting the nest from dirt or waste. The second layer has more threads than the first layer. It’s the tangled part where the spider hangs most times.
The third layer is made up of vertical sticky weaves to trap crawling insects.
Egg Sac
Black widow spider egg sacs are grey, usually spherical, around 9.5 mm in diameter, and have a distinct notch at the tip. Each egg sac houses 250-300 eggs.
Also, the female spider has about 8-10 egg sacs. It can form an egg sac within an hour. If you see a silken sac with eggs in your doorway or crevices, there’s an ongoing infestation.
How to Prevent a Black Widow Infestation
Now you know when black widows infest your home, how can you prevent an infestation?
- Reduce the clutter in the dark, hidden areas like garages and basements as they are hiding spots for black widows.
- Use oil-based insecticide like Pyrethrin on egg sacs. It would be best if you used the insecticide in small quantities.
- Essential oils are known to repel insects. Mix peppermint oil and water and spray in areas around the house to keep black widows away. You can use vinegar or Terro spider killer spray to eliminate black widows.
- Keep spider baits around corners to draw black widows out of their hiding places. Once the bait captures the arachnid, dispose of them immediately.
- Use a silicone-based sealant to cover gaps and cracks within the home to prevent black widows from hiding there.
- Ensure you wear gloves when handling black widow and its egg sacs.
- Spray plant-friendly insecticide in your garden or yard to eliminate black widows.
Now you have a broad understanding of black widow infestation signs, where they live, and how to prevent infestation.
If you want to completely get rid of black widow spiders in your home, consider contacting an extermination specialist.