Are Black And Yellow Garden Spiders Dangerous

Yellow Garden Spider

Argiope aurantia

Status: Not Listed

Classification: Invertebrate

Description

Yellow garden spiders are large, orb-weaving arachnids, meaning they spin a circular web. Most spiders have two claws on each foot, but orb weavers have an additional claw to help them spin their complex webs. In females, the top side of the abdomen is black with symmetrical patches of bright yellow. The legs are reddish brown at the base and black toward the tips. Males are less striking in appearance—they are smaller with brownish legs and less yellow coloration on their abdomens. Females average 0.75 to 1.1 inches (19 to 28 millimeters) in body length, which is up to three times larger than the males.

Range

Yellow garden spiders can be found throughout the continental United States and Canada, Mexico, and Central America. They spin webs in sunny areas with plants on which they can anchor the webs. They may also be seen in backyard gardens.

Diet

These spiders produce venom that is harmless to humans, but helps to immobilize prey like flies, bees, and other flying insects that are caught in the web. The web of the garden spider contains a highly visible zigzagging X-shaped pattern called a stabilimentum. The exact function of the stabilimentum is unknown, but its purpose may be to alert birds to the presence of the web so that they don't fly through and destroy it by mistake. The spider may eat and respin its web each night.

Life History

A male seeks out a female and courts her by plucking at her web. After mating, the female deposits one or multiple egg sacs on her web. Offspring hatch in late summer or autumn. If they're in an area with a cold winter, the young spiders may remain in the egg sac in a dormant state and emerge in the spring. Egg cases are heavily parasitized by wasps and flies. On average, the garden spider lives for about one year. Females usually die in the first hard frost after mating. If temperatures prevent this, females may live several years, but males usually die after mating.

Conservation

Garden spider populations are stable. They are common and widespread.

Fun Fact

Sometimes the garden spider connects itself to a web by a thread of silk and hides in the underbrush. When an insect gets caught, the spider can feel the vibrations of the web.

Sources

Animal Diversity Web, University of Michigan Museum of Zoology

Encyclopedia of Life