The black widow is a small, shiny spider famous for its red hourglass marking and potent venom. It is actually shy and non-aggressive, and it helps control insect pests.
Interesting facts
- Females are glossy black with a red hourglass mark on the underside of the abdomen.
- Males are much smaller and are usually harmless to people.
- Females occasionally eat males after mating, but this is less common in the wild than its name suggests.
- Black widow silk is exceptionally strong and was once used for crosshairs in gun sights.
- Each egg sac can contain hundreds of eggs.
- Black widows are shy and bite only when pressed against skin.
Behaviour
Black widows build messy, tangled webs close to the ground and hang upside down in them, often at night. When prey becomes stuck, the spider wraps it in silk and bites it.
Breeding and young
Females produce several round, papery egg sacs over the summer, each with hundreds of eggs. Spiderlings disperse by releasing silk threads and floating on the wind.
Threats and conservation
Black widow spiders are common and not threatened.
Where to see it
- Woodpiles, sheds and stone walls in the southern United States
- Deserts of the southwestern United States
- Spider and insect houses at zoos
- Wear gloves when moving wood or stones
Status source: IUCN Red List. Profile last reviewed September 2026.
