About: There are more than 35,000 species of spiders worldwide, a few thousand of which are found in the United States alone. Spiders rarely bite people and in the United States only two groups - the Black Widow and Brown Recluse spider - are considered dangerous. The bite of most spiders has little to no effect on people, while a few others are of minor medical importance.
Spiders can be a particular nuisance in the home. They are attracted to warm, dark small spaces, like wall cracks, corners, air vents, and in the eaves of your home.
Other species prefer to stay closer to the outdoors, weaving their webs in your barn, back yard or near your outside lighting. Most spiders are a nuisance primarily because of their webbing and because many people have an inherent fear of spiders.
Spiders are often beneficial because they eat many types of insects, including those that are pests like ants, cockroaches, flies, mosquitoes and moths.
Egg – Embryonic Stage
After mating, female spiders store sperm until they are ready to produce eggs. The mother spider first constructs an egg sac from strong silk that is tough enough to protect her developing offspring from the elements. She then deposits her eggs inside it, fertilizing them as they emerge.
A single egg sac may contain just a few eggs, or several hundred, depending on the species. Spider eggs generally take a few weeks to hatch. Some spiders in temperate regions will overwinter in the egg sac and emerge in spring.
In many spider species, the mother guards the egg sac from predators until the young hatch. Other species will place the sac in a secure location and leave the eggs to their own fate.
Wolf spider mothers carry the egg sac with them. When they're ready to hatch, they will bite the sac open and free the spiderlings. Also unique to this species, the young spend as many as ten days hanging onto their mother's back.
Spiderling – Immature Stage
Immature spiders, called spiderlings, resemble their parents but are considerably smaller when they first hatch from the egg sac. They immediately disperse; some by walking and others by a behavior called ballooning.
Spiderlings that disperse by ballooning will climb onto a twig or other projecting object and raise their abdomens. They release threads of silk from their spinnerets, letting the silk catch the wind and carry them away. While most spiderlings travel short distances this way, some can be carried to remarkable heights and across long distances.
The spiderlings will molt repeatedly as they grow larger and they're very vulnerable until the new exoskeleton forms completely. Most species reach adulthood after five to ten molts.
In some species, the male spiders will be fully mature as they exit the sac. Female spiders are always larger than males, so often take more time to mature.
Adult – Sexually Mature Stage
When the spider reaches adulthood, it is ready to mate and begin the life cycle all over again. In general, female spiders live longer than males; males often die after mating. Spiders usually live just one to two years, though this does vary by species.
Common Indoor Spiders
Common House Spider - spider most often encountered indoors.
Cellar Spider - very long, thin legs; will rapidly shake its body on the web when disturbed.
Wolf Spiders - large, “hairy”, and often mistaken for tarantulas; leg span as much as 3 inches.
Sac Spiders - often pale yellow, grey, or green color; likely responsible for most indoor spider bites.
How Pest Management works: A professional Pest Control Technician has the equipment and training to do a thorough job and has access to products not available over the counter. Additionally, your pest expert can identify the species and put together a pest management program that is specific to your needs.
How can you help: Spiders are most likely to enter the home in the fall
due to their search for a warm place to spend the winter.
There are several ways that you can help to get rid of and prevent spider problems in your home:
Remove noticeable webs
Fill in gaps in walls and under doors to deter entry
Remove sheltering sites like firewood piles and compost piles from near your home
Use lighting in a way that is less attractive to the insects that spiders feed on