What makes spiders problematic?
Spiders are one of the most common pests we service at Cascade Pest Control. They cause unsightly webs that attract and accumulate insects and dust. Spider webs over picture windows can obstruct views and annoy homeowners. Spiders crawling indoors can be startling.
Spiders are not insects, but “arachnids,” as they have eight, not six legs and eight eyes. Spiders are carnivorous and primarily eat insects. Interestingly, spiders liquify their food before ingesting it.
Most spiders are venomous but only toxic to tiny insects. A rare few are toxic to humans. And all spiders have blue blood. We have red blood because it uses iron to bind to oxygen, while a spider’s blood uses copper to bind the oxygen, giving it a blue color.
Are there poisonous spiders in my area?
Although all spiders possess venom, most spiders cannot harm humans and are only able to dispatch small insects. Whether there are spiders of any significant danger to humans near you depends on where you live.
Also, some people are susceptible to the most minor spider bites and have mild reactions, similar to a mosquito bite and, rarely, could have a more serious allergic reaction to them. The poisonous spiders of concern in Cascade’s service areas in Idaho and Washington are as follows:
In Idaho (Boise / Treasure Valley):
The Western black widow can be found within the greater Boise / Treasure valley area.
The black widow spider bite can cause a significant amount of pain, as well as nausea, fever, and an elevated heart rate. Immediate medical attention is warranted. Black widow spiders are shiny black in color with a red “hourglass” marking on the bottom side of the abdomen. They are found in piles of debris, in outhouses, sheds, in firewood piles, carports and garages. [There are no brown recluse spiders in this area.]
Citation: Black Widow Spider. Article in Wildlife Express, Vol 31/Issue 2 October 2017. Idaho Fish and Game.
In Washington (Puget Sound region):
There are two spiders of concern in the state of Washington—the yellow sac spider and the black widow spider. Black widows are only found in eastern Washington (despite a couple of erroneous Internet statements to the contrary). Yellow Sac spiders, however, can be found in Western Washington, including the greater Seattle area.
Yellow sac spiders have a small body measuring between ¼” and ½”, and they can be yellow, white, or even have a greenish tint. Their legs and upper body are darker than their abdomen. They bite when they feel trapped against a person’s skin. Their bites are painful and can result in an ulcerative sore that takes a long time to heal.
Special Note: False black widow spiders are present in the greater Seattle / Puget Sound region. They have a close resemblance to the black widow spider; however, they are all black or very dark brown, lack any red markings on the abdomen, and do not have the toxins that the black widow spider possesses.
Citation: Spiders. Washington State Department of Health.
Do I have a spider infestation?
Spiders do not form social colonies or congregate. Spiders mostly just find their own spot to hunt, either using a web or by pouncing on prey. Spiders will breed and spread out until they’ve covered the territory that has food resources. And spiders will always be attempting to spread out onto, and if they can, into your home.
So, a “spider infestation” is more a matter of how many spiders you want to tolerate in your living space, inside or out. Many people find spiders disgusting and startling, and just don’t want them around. Others tolerate them a fair amount, knowing that they, too, fit into the scheme of things. In the case of these folks, it’s when the sightings and webs are just too much, then they might decide “we need a reset.”
How can I get rid of spiders?
Since your home has cracks and crevices where hunter spiders can hide and surfaces over which webbing spiders can cast their nets, they will feel inclined to set up shop. To eliminate spiders, consider a professional pest control service, which will manage both the spiders and the many insects that are attracting the spiders in the first place.
How can I prevent a re-infestation of spiders?
First, ensure that any outdoor lights use bulbs that do not attract insects (insects that spiders will hunt, bringing them into your proximity.) Second, keep the house well-sealed, and when opening windows in the summer, use tight-fitting screens.
Having a pest management company periodically spray for spiders and remove spider webs outdoors will make your home look nice and reduce the number of spiders that could otherwise find their way inside.
A pest control company can also help to control the insects that are attracting the spiders in the first place.
