Overall, we realize not everyone loves spiders, but they do manage to make themselves useful in the natural world and can be interesting to study. Remove them from your home if you will, but refrain from using pesticides when possible.
What Do Spiders Look Like?
Spiders are classified as arachnids that have two body parts and eight legs. In other words, they are not insects! They are closely related to mites, ticks, and scorpions. Spiders come in many shapes, sizes, colors and forms, and are found throughout New York state. Spiders can be identified to family by looking at their eye patterns, if you happen to get close enough. This is important because common, harmless species are often confused with the dangerous spiders that are unlikely to occur in New York State.
Should I Worry About Spiders?
Generally, no. A common fear about spiders is the bite of a dangerous or venomous species. However, this is extremely unlikely because the brown recluse spider does not occur in New York, and black widow spiders are found primarily in dark, moist areas where people are unlikely to interact with them. The instances when people do encounter black widow spiders is when hands or feet are stuck into dark, damp areas without proper protection (gloves, socks).
This is not to say that other spiders will not bite. If handled or threatened, spiders may bite in defense. Storing shoes outdoors or in a basement creates a habitat for spiders that can then bite if a sockless foot is placed inside.
An important note: Harvestmen, sometimes called daddy-long-legs, are a type of arachnid related to spiders. They have eight legs and seem to have just one body segment (not two like spiders). Misinformation about these arachnids claims that they have a venomous bite, but their mouthparts are not big enough to pierce the skin, nor do they have venom glands. The truth is that these arachnids are mostly detritivores – feeding on decaying organic material, and put plainly, daddy-long-legs are common and harmless.
Why Do I Have Spiders?
As a group, spiders are predators that feed on other, smaller critters. The various spider groups obtain food in different ways: some actively hunt for food while others build webs to ensnare prey. Spiders also differ in their preferred habitat: some spiders enjoy cool, dark places and some live in open meadows and fields. Therefore, the reason that spiders may enter your home depends on the type of spider and its preferred food source. Some ideas to consider and generalizations that may apply:
Attraction to Light
Web-building spiders, such as orb-weavers, preferentially build webs next to a light source, or reflective surfaces (glass, mirrors) that catch light. This is because those same sources of light are attractive to flying insects – which serve as spider food.
Damp Underground Areas
Cool, dark places are attractive to small creatures that serve as spider food. Areas beneath fallen trees, under rocks and other natural cave-like structures are home to spiders, which explains why basements and crawl spaces are attractive for these arachnids.
Although some spiders move to new locations by walking, many spiders disperse by a process called ballooning. In this process, silk is used to catch the wind and lift a spider into the air. As a result, they can be spread far distances to new locations. This means that even if you somehow eliminated every spider in your yard in the middle of summer, it could be quickly repopulated by new, dispersing spiders.
How Do I Get Rid of Spiders?
Spider management depends on identification, and determining why the spiders are present. Below are recommendations that apply to specific types of spiders.
Change Light Patterns
Many web-building spiders prefer to live near a light source or reflective surface. You can reduce the attractiveness of your home to flying insects and therefore spiders by assessing the light profile of your home. The first step is to select bulb types that are less attractive to insects (cool LED or yellow lights). The more expensive fix is to change lighting so that beams of light face the house from the yard instead of fixtures that are attached to the structure. Insects will be attracted to the light source, and not the home.
Remove Webbing Material
Repeated removal of spider webs can displace spiders.
Preventing spiders from accessing damp, below-ground areas requires physical exclusion. Consider gaps found around windows, doors, and at the sill plate (where the stone/cement foundation meets the wooden frame parts of the home). Spiders are arthropods with flexible exoskeletons, which allows them to compress their bodies and enter tiny openings. Therefore, gaps should be closed with an appropriate sealant that is flexible and durable. Closing these gaps will reduce other pests as well.
Monitoring for spiders can be accomplished using insect sticky traps. Folded over and placed in areas where spiders have been observed will allow you to obtain specimens that can be identified by an expert.
Captured spiders can also removed from the home by placing a cup over the spider and then sliding a piece of paper under it to trap the spider in the cup. Place it outside on vegetation away from the house.