Identification
Black widow spiders are glossy black with a distinctive red hourglass marking on the underside of their abdomen. They measure about 1.5 inches in length, including their legs. Males are smaller and have lighter coloration with additional white or red markings. They have eight legs and a round abdomen.
Lifecycle & Reproduction
Black widow spiders undergo incomplete metamorphosis, progressing from egg to spiderling to adult. Females lay egg sacs containing 200 to 900 eggs, which hatch in 2 to 4 weeks. Spiderlings undergo several molts before reaching adulthood in 2 to 4 months. Females can live up to three years, while males have a significantly shorter lifespan.
Habits, Diet & Behavior
Black widows are nocturnal and prefer to spin irregular webs in secluded areas. They primarily feed on insects such as flies, beetles, and grasshoppers. Females are more aggressive when guarding eggs, while males are not known to bite. Their venom contains neurotoxins that affect the nervous system.
Where You’ll Find Them / Typical Locations
Black widow spiders prefer dark, sheltered spaces, including:
- Garages, sheds, and basements
- Woodpiles, stone piles, and debris
- Crawl spaces and under porches
- Outdoor furniture and play structures
- Undisturbed corners of attics and storage areas
Threats & Danger
Black widow spider bites can cause severe pain, muscle cramps, nausea, and sweating. Though rarely fatal, their venom is highly potent, requiring medical attention for severe reactions. Young children, the elderly, and individuals with weakened immune systems are at greater risk.
Prevention
- Seal cracks and gaps around doors, windows, and foundations
- Remove clutter and debris where spiders may hide
- Store firewood at least 20 feet away from buildings
- Shake out shoes, gloves, and stored items before use
- Use outdoor lighting that does not attract insects
Signs of Infestation
- Presence of messy, irregular webs in dark, undisturbed areas
- Sightings of glossy black spiders with red markings
- Egg sacs attached to webs in sheltered locations
- Increase in insect activity near nesting sites
- Bites that cause localized pain and muscle cramping
How to Get Rid of It
- Remove webs and egg sacs using a vacuum or broom
- Apply insecticides in corners, cracks, and outdoor hiding spots
- Use glue traps to monitor spider activity indoors
- Reduce insect populations to eliminate food sources
- Contact a professional pest control service for persistent infestations