black widow spider

The Black widow spider is one of the most poisonous and dangerous spiders in North America. They are usually identified by their black color and red marking on the underside of their abdomen, also called the opisthosoma. This red marking is usually shaped like an hour glass.

They Are Arachnids

Black widow spiders are not insects. They are Arachnids, meaning they are part of the animal class Arachnida. Since they are arachnids they only have two body segments (unlike insects, which have three). They also have eight legs.

What do they look like?

The female black widow spider is darker and larger than the male. Where the female is usually dark black, the male is often dark brown and doesn't have as bright red of an hour glass shape on the abdomen. The female can grow to about ½ an inch long body and 1 ½ inch leg span. The male black widow is typically around the half the size of the female.


How poisonous are they?

The black widow spider is the most poisonous spider in North America. The male and young black widows are generally not considered dangerous to humans. Upon getting bitten by a black widow, you should seek medical attention immediately. If you can catch the spider, it will be helpful in identifying the type of spider and potential medical remedies. If you see a black widow, do not play with it. Tell your parents or your teacher immediately.

Where do they live?

The female black widow spider generally builds her webs low to the ground. Once she finds a good spot and builds her web, she will often stay in or around her web for the majority of the time. Most of the time she will hang belly up within her web, making identification of the hour glass mark easier. This also warns off predators, which will recognize the bright color and not want to eat her. Even though eating a poisonous spider might not kill a predator, like a bird, it can make them sick.

What do they eat?

Black widow spiders are carnivores. They eat insects that they catch in their web such as flies, grasshoppers, beetles, and mosquitoes. Sometimes the female will kill and eat the male spider, which is how the black widow got its name.

Do they lay eggs?

The female will lay 100's of eggs at a time. The eggs sit in a cocoon spun by the mother until they hatch. When they hatch they are on their own with only a small percentage typically surviving.

Fun Facts About the Black Widow Spider

The poison from a black widow spider is 15 times as potent as the poison from a rattlesnake. A black widow will inject a lot less poison than a rattlesnake in a typical bite, however.

Black widows can live up to 3 years.
Although black widow bites can be fatal to young children, most people do survive.
Common predators include the wasp, praying mantis, and birds.
Not all black widows have the red hour glass on their belly, so its best not to mess
with any black spiders.
They like dark areas and are nocturnal.
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