Question: What are the big red spiders that are outside and on my porch?
ANSWER: From your question, I am assuming that you are seeing these spiders in webs, maybe in plants around your porch. With this in mind, you probably have an orb-weaving spider. It could possibly be a red orb weaver (Araniella displicata), which is a harmless spider. This is a large family of spiders, and several hundred species are found in the U.S. Almost all of these spiders spin a large and sometimes complicated web of concentric rings. They often locate the webs on the sides of houses or on trees and shrubs, especially near outdoor lights.
Orb-weaving spiders are often brightly colored and attract attention as they sit in or near their web. They are waiting for prey to become stuck and shake the strands.
Some of the most dramatic of the orb weavers are the spiders in the genus Argiope. These spiders are striped black and orange, or black and white. They construct large webs that have a zig-zag pattern of silk in the center of the web. They are usually found hanging head down in the center of the web.
While orb-weaving spiders are large and look threatening, they are not aggressive to people. Certainly, you can be bitten if you try to handle one of these spiders, but they will usually try to get away from people. When their web is damaged, they will usually leave and rebuild it somewhere else.
Limiting the use of outdoor lights at night can help reduce the number of flying insects that gather there. These insects are the food for these and other spiders around the outside of the house. Changing porch lights to the yellow “bug light” bulbs may help. It is sometimes necessary to place curtains or shades on windows to reduce the amount of light that shines out to attract flying insects. While none of us really likes many of these spiders around our homes, outside they are being beneficial by preying on other insects that may even cause harm to your plants.
If you wish, call your local Orkin branch, and a trained Orkin Pest Specialist will come to your home, conduct an inspection of the inside and outside, and recommend a treatment plan to eliminate conditions and food sources that may be attracting these spiders.