California is the one of the largest states in the United States, and as such, thousands of species of spiders make residence there. With such a large spider population, as well as a huge human population, it is inevitable that some spiders will make their way into human dwellings. Though there are few spiders in California that are dangerous, it is a good idea to have some knowledge about the spiders you are likely to encounter in your home.
One of the most common types of spider in California is the wolf spider, sometimes even called the California wolf spider. These spiders are easily recognized by their thick long legs, along with brown and black color. Wolf spiders get their name from the fact that they actively hunt their prey (usually small insects on the ground), rather than spinning a web and waiting like many other spider species, and they often make their way inside houses as they stalk their prey. Because they have no web on which to place their egg cases, wolf spiders will carry their eggs around with them in a sac cradled beneath their abdomen. After hatching, the young spiders will cling to their mother's legs until they are big enough to venture out on their own. Although wolf spiders are generally not aggressive, if threatened they are capable of inflicting a sharp, stinging bite that can result in localized swelling.
American House Spider
Another spider likely to be encountered inside California homes is the American house spider (Parasteatoda tepidariorum) also known simply as the common house spider. These spiders are rather small and stubby in appearance, often measuring no more than 1/4-inch long. House spiders are normally a drab, brownish color, with a speckled or spotted appearance. They will make their webs behind doors, in the crevices of walls, and in corners. Their diet consists mainly of small insects that they trap in their web, although on rare occasion, larger house spiders will catch small lizards. House spiders generally try to avoid direct contact with humans, often trying to escape or even playing dead when threatened.
One of the most infamous spiders located in California is the black widow (Latrodectus hesperus), sometimes called the western widow in the California region. Black widow female spiders are easily identified by their black color, with a red hourglass shape located on their abdomen. The females typically grow to one and half inches with legs fully spread, while the males are about half that size and are a drab brown color. Black widows will spin their web in just about any place they can find shelter, including deck ares around houses, in garages, under crawl spaces, and sometimes in even inside houses. Females are known to bite if their web is disturbed, and humans should avoid contact with these spiders. Black widows are the most venomous spider in North America, and immediate medical attention should be sought if a bite occurs.