There are numerous species of spiders found throughout Western Washington. While most are relatively harmless, some are quite venomous. How the venom from a spider bite affects an individual will largely depend on multiple factors, such as age of the victim, general health, and sensitivity.

Here is some general information to help identify the more venomous species of spiders found in Washington:

The Hobo Spider

The hobo spider, also known as tegenaria agrestis or the “aggressive house spider,” is among the most common house spiders found here in Western Washington. They build funnel webs in moist, dark areas to ensnare their prey, and can often be found in window wells and basements. Hobo spiders can be identified by their long, hairy legs, dark brown color, and unique yellow pattern located on the abdomen. They can appear somewhat large in size (7/16 – 10/16 body length in inches), and are known to be swift runners, but poor wall climbers.

The bite from a hobo spider has been described as a slight prickling sensation, followed by an insensitive, small hard area that reveals itself within 30 minutes, surrounded by a reddened area 2″- 6″ in diameter.

The Brown Recluse Spider

The brown recluse (also known as loxosceles reclusa or the violin or fiddleback spider) spins irregular webs and prefers to hide in crevices, cracks, and beneath furniture. They can be identified by their long legs and their color, which varies from a light fawn to a darker chocolate brown. However, its most defining feature is the dark brown fiddle shape located on its back. Overall, they are somewhat smaller than the black widow, with the females being slightly larger than the males.

Both sexes deliver a venomous bite. Since the brown recluse spider has not yet established itself in the Pacific Northwest, its bite is often times confused with that of the more common hobo spider, which produces similar skin injuries/lesions. The typical reaction followed by a bite is delayed tissue death.

The Black Widow Spider

The black widow spider (latrodoctus hesperus) can be easily identified by its dark black bulbous body and red hourglass marking located beneath its abdomen. The immature black widow and male black widow are smaller in size than mature females, and will in general have white, yellow, and red spots/bands over the back.

Though more common to Eastern Washington, we do occasionally find black widows in Western Washington. Typically found in dark outdoor places such as sheds, privies, garages, beneath homes, and in littered areas, the shy black widow spins amorphous webs. Its venom is a nerve toxin, and its bite has been described as a burning sensation that can last for a few minutes after the initial bite.

The pain typically then progresses through the bitten limb and localizes to a certain degree in the back and abdomen, causing muscles to stiffen and become rigid. This is usually accompanied by abdominal cramping, along with other symptoms that may include tremors, nausea, speech defects, insomnia, depression, and a rise in temperature. These symptoms may manifest within minutes or hours of the bite, and while it can be painful, it is not often fatal.


There are many things that you can do to prevent spiders from taking over your home or business.

  • Eliminate small cracks and openings to your house with the use of sealants (i.e. caulk) and snug fitting screens and doors

  • Get rid of clutter (boxes, furniture, etc.)

  • Keep a clean living environment

  • Wear full-length pants, a long-sleeved shirt, and protective gloves when removing webs or when moving stored wood, boxes, etc.

  • If there is a spider on you, be sure to brush it away. Crushing it increases the risk of a bite!


We understand that your needs can be urgent. Our goal is to provide you with a pest-free home or business as quickly as possible. Call before noon Monday – Friday and a Sentinel professional will be at your door the SAME DAY!


Have any pest related questions or in need of pest control services?

Our office staff is trained to answer any pest control related questions! Once scheduled with us, an appointment confirmation will be emailed within 15 minutes with your appointment information and a picture of your technician!


We’ll give you a call and schedule the best time for you!