The Tarantula: A Docile, Not Deadly, Spider

Tarantula crawling over tree branch.
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Although tarantulas are often thought to be dangerous, they are not deadly spiders and they rarely bite except in self-defense. When a tarantula does bite a person, it is usually because it is being handled (or stepped on by a barefoot) and is no more serious than the sting of a bee. However, just as some people are allergic to bee stings, some may be allergic to the bite of the tarantula or other spiders.

Tarantula Identification

  • Tarantulas are the largest spiders in the world. They can range from 1 to 4 inches in body length with leg spans of up to one foot (12 inches).
  • They have long lives. Females can live up to 30 years, but males will live no more than 10 years and their lifespan is often less than a year.
  • Tarantulas have dark brown bodies and legs, with reddish hairs on their "backs."

Where Tarantulas Are Found

In the U.S., tarantulas are found primarily in the southern and southwestern states, but they have been found as far north as Utah. They live in underground burrows, coming out at night or, in summer and fall, to mate.

Tarantulas can be found in homes ... but most often because one is being kept as a pet.

What Tarantulas Do

Tarantulas are nocturnal, that is, they are most active at night. They do not usually wander far from their burrows.

During mating season, however, males will journey far from their nests, if needed, to find females. The male will "knock on the door" of a female's burrow (tapping on the burrow's web). The female may ignore him, respond by coming to out to mate, or simply eat the wooing male if she is hungry.

They are actually shy, docile creatures, but a tarantula can seem to be aggressive when it feels threatened: rearing up on its back legs and exposing its fangs ready to attack.

Tarantulas eat insects, such as grasshoppers, beetles, and crickets. They are also known to eat small birds or mammals. Birds, snakes, tarantula hawks, foxes, some desert animals, and even other tarantulas, will prey on and eat this spider.

The Tarantula Bite

Contrary to popular myth, the bite of tarantulas is not deadly to humans. Some African species can cause painful, or even hallucinogenic reaction, but this is rare and fairly unknown in the U.S. As with all spiders, tarantulas are venomous, however, their poison is not dangerous to humans, and generally has little more impact than a bee sting - unless one is allergic to its venom.

The tarantula also has barbed, venomous hairs on its belly which it can throw in self-defense, causing severe irritation to an attacking animal.

If you are bitten, you are advised to seek emergency medical treatment, especially if any allergic reactions occur.

How to Control Tarantulas

Because female tarantulas rarely leave their burrows and males venture out only in search of females, it is rare to encounter one in the home. Thus, most experts recommend that you capture and remove the tarantula rather than killing them. That said, there are things you can do:

  • Utah State University Cooperative Extension suggests that if a tarantula does enter your home, "put an open container on top of the spider and slide a piece of paper under the opening. Then, flip the container and paper together, trapping the spider inside. The spider can then be safely released outdoors."
  • Spiders tend to spin their webs in quiet, undisturbed areas, so you can discourage them through frequent cleaning and vacuuming of these areas, such as closets, cellars, corners, etc.
  • Keep tarantulas out of your home by keeping doors closed, sealing structural gaps, and mending screens around the home.
  • To get rid of a tarantula that wanders into your home, or another unwanted area, you can implement general spider control methods.