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Black Widows

Identification of Mature Female

  • Large, black, shiny body
  • Measures approximately 3/8 inch long with 1-inch legs
  • An hour-glass shape of bright red or orange-red color can be found on her abdomen
  • Webs are very irregular, white in color and strong; they can be found under outdoor furniture, barbecue grills, pool pumps, storage areas and corners of porches and patios, and often where insects are readily available

Bite Symptoms

  • The initial bite may feel like a pin prick, which may go unnoticed - you may experience little or no visible signs of the bite such as swelling
  • A red circular mark may appear about six hours after the bite
  • Initial symptoms may be progressive aching sensations
  • There may be muscle pain at the bite site spreading to the abdomen,lower back, thighs and limbs
  • Symptoms last as long as 36 hours and lingering effects may last for several weeks

Treating a Bite

Call the poison center immediately at (800) 222-1222 to find out whether the bite victim can be cared for at home or will require treatment by a doctor or hospitalization. Severe cases may require anti-venom treatment.


A black widow hides near its web by day, typically in a sheltered spot, and is active at night waiting on its web for prey. She does not hunt for prey.

  • Inspect your yard for the irregular white webs
  • To control the black widow population find the webs at night using a flashlight and spray her directly with a strong insecticide and destroy all egg sacs; the egg sacs are small round white balls that contain hundreds of baby spiders
  • Wear gloves when handling firewood, lumber, and rocks - be sure to inspect the gloves for spiders before putting them on


There are many labeled pesticides for spider control. Some are labeled for homeowner use, while others are labeled only for the licensed, certified pesticide applicator. You'll want to spray the insecticide directly on the black widow.

If you have questions, please call us directly at (602) 253-3334 or call (800) 222-1222 for your local poison center.