Black widow spiders are common in Florida. There are two species of them here, the southern black widow (Latrodectus mactans) and the northern black widow (Latrodectus variolus). Southern black widow females are shiny black and have a red hourglass on their undersides. Northern black widow spider females are shiny black but the hourglass can be incomplete or missing. They have red spots up the middle of their back and may have white stripes on the sides. Female bodies range from 8-13 mm. Males of both species are much smaller (4-6 mm), black, and have white spots with some red on the underside. Both species are primarily nocturnal.
Lifecycle Of Black Widow Spiders
Female black widow spiders usually mate during the spring or summer, then produce a beige egg sack and lay an average of 220 eggs in it. She puts the egg sacks in her web and guards the eggs to keep predators away. In about a month, spiderlings are born white with no spots or hourglass on them. Each molt brings them closer to the adult coloring scheme. Females live for 1.5 years and males live for 3-5 months. Females may have as many as 9 egg sacks during their lifetime, so they reproduce and take over fairly quickly.
Places Black Widow Spiders Live
Black widow spiders are generally timid and only bite when they feel threatened or are guarding an egg sack. They used to be found under the toilet seat in outhouses, so people had to remember to check for them before being seated. They also frequent attics, garages, and basements. They often hide in shoes, clothes, and boxes so shake out clothes and shoes before putting them on. In nature, black widow spiders like dark sheltered places such as under logs or stones, in stumps, in rodent burrows, in rock piles, and in log piles. Their webs are disorganized and skimpy.
Only adult female black widows have long enough fangs to pierce human skin. Black widow bites are dangerous. The venom is 15 times more powerful than a rattlesnake's venom. Fortunately, the venom is only injected in small quantities. The bite area does not generally swell, but there may be a rash around it. It is a neurotoxin, so the bite is initially painless. In 1-2 hours, bite victims begin to feel pain. Sometimes people feel tingling in the nerves or around the spine. The person may experience any of these more general symptoms: nausea, chills, slight fever, rise in blood pressure, retention of urine, burning sensation of the skin, fatigue, motor disturbances, breathing difficulty, constipation, and muscle aches. Deaths are rare, but it is important to get medical attention when you are bitten. There is an antivenin available, but it works best soon after the bite symptoms start occurring. Pregnant women are most at risk and it can affect the pregnancy.
As mentioned, black widow spiders are timid and usually only bite in defense of themselves and their egg sacks. Here are some things you can do to help keep from getting bitten.
- Wear gloves when working in areas they frequent, such as barns, basements, attics, and other dark places.
- Stack firewood away from the house, as black widows love to live in woodpiles.
- Seal cracks and crevices in your foundation so they cannot enter your house.
- Seal gaps around pipes, electrical wires, and cables where they enter your house.
- Make sure you have screens that do not have holes.
- Check door sweeps and make sure they are working properly.
- Shake out clothes that have not been worn for a while.
- Shake out your shoes before putting them on.
Get Professional Help
Because black widow spiders are so dangerous, it is crucial to get professional help when dealing with an infestation. Green Flag Services will give you a free quote on our services. If you are interested, we will send a technician out to do an inspection and the initial treatment. We use eco-friendly products to get rid of spiders. They will not harm you, your family, or your pets. Call Green Flag Services today to schedule an inspection.