Characteristics: The common house spider in New Jersey is typically small, measuring about 1/4 to 1/2 inch in length, with a brown or grayish color and various patterns on its body. It often has a rounded abdomen and spindly legs, making it easy to spot in its web.

Behaviors: House spiders are known for spinning messy, irregular webs in corners, windows, or ceilings. They are not aggressive and usually hide when disturbed. Their webs catch prey, such as flies or other tiny insects. Once their webs become inactive, they usually abandon them and build new ones elsewhere

Risks: House spiders pose little to no risk to humans. While they may bite if directly threatened, their bites are rare and typically harmless. The real concern with house spiders is the annoyance of their webs and the aesthetic nuisance they cause. House spiders are more of a household pest than a threat, helping to control other insect populations inside the home.

Characteristics: Wolf spiders in New Jersey are typically larger than most house spiders, ranging from 1/2 inch to over 2 inches. They have robust, hairy bodies, usually brown or gray with distinct, dark markings. Their strong legs and keen eyesight (thanks to their eight eyes arranged in three rows) make them formidable hunters.

Behaviors: Unlike many spiders that rely on webs to catch prey, wolf spiders are active hunters. They use their speed and agility to chase down insects and other small prey, often stalking them before pouncing. Wolf spiders are nocturnal hunters, making them more active at night.

Risks: Wolf spiders, despite their intimidating appearance, pose minimal risk to humans. These spiders are not aggressive and will typically avoid contact unless provoked. If a bite occurs, it usually results in mild pain, redness, and swelling—similar to a bee sting—but is rarely dangerous unless an allergic reaction is triggered. While wolf spiders have venom, they subdue their prey and are not harmful to humans. The real concern with wolf spiders is more psychological, as their large size and quick movements can be alarming when found indoors. Overall, they are more of a nuisance than a threat and are actually beneficial in controlling other pests.

Characteristics: Cellar spiders in New Jersey are easily recognized by their long, thin legs and small bodies, often earning them the nickname “daddy longlegs.” Their body length ranges from 1/4 to 3/8 inch, with legs that can be several times longer. These spiders are typically pale yellow, light brown, or gray.

Behaviors: Cellar spiders are web-builders, constructing loose, irregular webs in dark, damp areas like basements, crawl spaces, and garages. They stay in their webs, hanging upside down, waiting for prey. Although they prefer undisturbed places, if their web becomes inactive, they will abandon it and build a new one. Interestingly, cellar spiders may also invade other spiders’ webs to capture prey, which can include insects and even other spiders.

Risks: For humans, cellar spiders pose no real threat. They are not aggressive and rarely bite. Even if they do bite, their venom is harmless to people. The biggest issue they pose is the nuisance of their webs, which can accumulate in corners and ceilings. Overall, cellar spiders are more of an aesthetic annoyance than a physical threat, and they help control other insect populations indoors.

Characteristics: Black widow spiders in New Jersey are small, shiny, jet-black spiders, easily recognized by the iconic red hourglass marking on the underside of their abdomen. Females, which are more dangerous to humans, are about 1.5 inches, including their legs. Males are much smaller and less threatening.

Behaviors: Black widows are web-building spiders that prefer dark, secluded areas such as sheds, garages, basements, woodpiles, and outdoor furniture. They create irregular, messy webs where they hang upside down, waiting for prey such as insects. Black widows are generally non-aggressive and will retreat if disturbed. However, they may bite if they feel trapped or threatened, particularly if they are defending their eggs.

Risks: Black widow bites are venomous and can be dangerous, especially to children, older adults, or those with compromised immune systems. Symptoms of a bite can include intense pain, muscle cramps, nausea, and sweating. Although bites are rarely fatal due to modern medical treatment, they require immediate attention. If you suspect a black widow bite, seek medical care promptly.

Fortunately, black widows are not commonly found indoors and pose a low risk as long as they are left undisturbed in their natural habitats.

Characteristics: Brown recluse spiders in New Jersey are medium-sized spiders, usually light to dark brown, with a distinctive violin-shaped marking on their backs. A brown recluse’s body size ranges from 1/4 to 1/2 inch, and unlike many other spiders, the brown recluse has six eyes arranged in three pairs rather than the usual eight.

Behaviors: True to its name, the brown recluse is shy and prefers to stay hidden. It dwells in dark, undisturbed areas such as attics, closets, basements, and storage boxes. Outdoors, they may hide under rocks, woodpiles, or debris. Brown recluses are nocturnal hunters and feed on small insects. They don’t spin webs to catch prey but use webs to create shelters. These spiders usually bite only when disturbed, such as when they’re accidentally pressed against the skin.

Risks: Brown recluse bites can be serious because their venom contains necrotic agents that may destroy tissue around the bite area. A bite can cause pain, redness, and in severe cases, ulcers or lesions that may take weeks or even months to heal. While most bites are mild, some can lead to systemic symptoms like fever, nausea, or fatigue. Although bites are rarely fatal, medical attention is often necessary.