How Do Black Widow Spiders Mate?


Female Black Widow Spider

  • One of the most dangerous spiders found in the United States is the female black widow spider. The female black widow has a shiny black, bulbous body, with long extended legs. A distinctive red or yellow hourglass shape marks the underside of her abdomen. The female's reputation for devouring the male after mating earned the spider its ominous name. While the female's after-mating eating habits have been accepted as standard behavior, it is not always the case.

Male Black Widow Spider

  • Scientists believe the male black widow is not dangerous to humans. The female weighs approximately 30 times more than her mate, with the male being about ¼ to ½ the size of the female, with proportionally longer legs. Instead of the hourglass marking, males may have white, red or yellow markings on thier backs.

Mating Ritual

  • The male black widow approaches his mate with caution, inching slowly onto the web towards his intended target. As he moves closer to the female, he taps his legs in a courting ritual to entice her into accepting his attentions. If she decides to acquiesce (instead of having lunch) she will stay still as he crawls onto her larger body and begins inserting his sperm. After he is finished, part of his body may break off, and is left behind in the female's body.

Killing the Mate

  • It is a general belief that the female black widow eats the male after mating. This is not always the case. It is not uncommon for the male to make a hasty and successful retreat after the mating. Scientific studies, which promoted the black widow image, were often done in confined areas and did not allow the male an opportunity to make a safe departure. Note that it is not uncommon for other types of female spiders to kill and dine on the males.

Fertilizing the Eggs

  • The female will store the sperm and fertilize her eggs when she lays them in the sac. Because of her ability to store the sperm, she only needs to mate once. The sac, which protects the eggs, is a white silken cocoon, about 1/2 inch in diameter. As the eggs mature the sack turns from white to light brown in color. Each sack can hold up to about 1,000 eggs. During the summer the female may produce four to nine sacs. It will take two weeks to a month for the eggs to hatch. The female black widow will eat most of her hatchlings, and normally less than a dozen will survive.

Promoted By Zergnet


You May Also Like

Related Searches

Check It Out

How to Build and Grow a Salad Garden On Your Balcony

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!