Some spiders are good for killing and eating insects like flies, mosquitoes and other pests. Other spiders can pose a health hazard to people. Some, like the black widow or brown recluse, have venom that is strong enough to sicken or even kill you. Children can be especially vulnerable because they are so small.
Spiders can enter your home through cracks in the walls, gaps in the window frames or by hitching a ride on fruit, in cardboard boxes or inside used furniture. Once they have found their way inside your home, they begin nesting and reproducing. That means you’ll probably find spider egg sacs in remote corners of your home.
Most spiders breed anytime except winter. They usually breed during the warmer months, and their eggs hatch in a matter of weeks. If they lay their eggs in late autumn, the babies won’t hatch for a few months. Tarantulas, trapdoor spiders and wolf spiders tend to mate in autumn. The spiderlings overwinter in their protective silken case.
How many eggs a spider lays depends on the type of spider. Smaller species can lay over 1,000 eggs. A low percentage of these spiders survive, which is why they have so many eggs. Other spiders only have about 10 eggs per sac. The larger species have fewer eggs, but they protect them more carefully. Some spiders, like the wolf spider, carry their egg sacs on their body. After they hatch, the babies get a free ride on mom until they are old enough to feed themselves.
It’s best to hire a professional to remove spider eggs if you find them in your home. Exterminators have the right training and materials to get rid of them for good.