Question: I was wondering about daddy long-leg spiders. We have a lot of them outside of our house, and it seems that where they hang out there are now tiny brown spots on our siding. Do they leave marks or feces behind?? Or is it from digestion? It just seems to be wherever the daddy long-legs are or hang out.
ANSWER: Outside you are probably dealing with harvestmen (order Opiliones), and the spots could be fecal deposits.
Daddy long-legs are not actually spiders, but are arachnids. They are predators like spiders, and feed primarily on insects, although some may eat plant material and can even eat solids. They are usually found outdoors and near outdoor lights because the lights attract insects, and the daddy long-legs can find plenty of food there.
Control of daddy long-legs can begin by reducing the outdoor lights at night, then using a broom to move them away from the door. They don’t bite people or pets and are rather harmless.
To control the insect population they normally feed on, contact your local Orkin branch office, and a highly trained Orkin Pest Specialist will inspect and develop a customized treatment to suit your needs.