Natural Wonders: Black Widow Spider

Black Widow spiders are considered deadly, with venom reported to be 15 times stronger than a rattlesnake’s, according to National Geographic.

Human fatalities from the Black Widow bites are generally rare, and the spiders only tend to bite to protect themselves from harm. Other insects, however, including male Black Widow spiders, are at the most at risk of death from the females spiders.

Identification

It’s the red hourglass mark or spots on the female Black Widow’s shiny black abdomen that make it stand out from other spiders. Female Black Widows are usually at least double the size of their male counterparts, and the female’s venom is what can be harmful to humans if they are bitten.

Black widows are an average size and shape of an elongated quarter, and they construct webs using silky fibers to catch prey. The spiders kill insects to eat, but will generally only bite a human or animal if they are threatened or smothered.

Range

Black Widows are considered to be the most venomous spiders in North America, and the species can be found in temperate regions all over the world. The spiders are commony found in America’s warm and desert regions, such as the American Southwest.

The spiders live under rocks, ledges, debris and plants—the areas where they dwell and create webs.

Existence

The female spiders lay eggs in the summer months, with several batches—each containing up to 750 eggs each. There are an average of 8 egg sacs produced in a summer, and only 1 to 12 eggs survive the incubation period of 14 to 30 days due to cannibalism.

About 90 days after egg sac emergence, female mature and live another 6 months to a year. Males mature about 70 days after emergence, but only live a month or two.