Centipedes are arthropods characterized by their elongated, segmented bodies and numerous pairs of legs. Each body segment bears a single pair of appendages, and they can have anywhere from 15 to nearly 200 legs. While they are venomous predators, their interactions with people are generally not a sign of aggression. Any potential harm is better understood as a defensive encounter, not an unprovoked attack.
Centipede Behavior and Temperament
Centipedes are solitary, nocturnal hunters focused on locating and subduing smaller prey. They are efficient carnivores, using speed and venom to capture insects, spiders, and other arthropods. Their activity is driven by the need to find food and maintain a moist habitat, as they are vulnerable to dehydration.
They do not view humans as prey and actively avoid confrontation whenever possible. The instinctive reaction of a centipede upon encountering a large animal is typically to flee and find cover. This avoidance behavior is a fundamental part of their survival strategy.
A defensive strike usually happens when a centipede feels threatened, is accidentally trapped, or is handled. The creature only deploys its venom when it perceives an immediate danger that escape cannot resolve. They are fully equipped for self-defense when cornered or crushed.
Understanding the Centipede Bite
Centipedes do not bite using traditional mouthparts. Instead, they use a specialized pair of modified front legs called forcipules or maxillipeds. These pincer-like appendages are located behind the head and are used to grasp prey while injecting venom through sharp claws. When a centipede strikes, it leaves two distinct puncture marks on the skin, often forming a chevron shape.
The effect of a defensive strike on a human varies depending on the centipede’s size and species. For most common house centipedes, the venom is weak, and the resulting pain is often compared to a bee or wasp sting. Symptoms typically include immediate, localized sharp pain, minor swelling, and redness at the site of the strike.
The discomfort usually subsides within a few hours, though it can last for a few days. While the reaction is rarely severe for the average person, the venom contains a complex mix of bioactive components. In rare cases, individuals may experience systemic symptoms such as nausea, headache, or swollen lymph nodes. An allergic reaction, like anaphylaxis, is possible but remains extremely rare, similar to other insect stings.
Why Centipedes Enter Homes and How to Manage Them
Centipedes are drawn into human dwellings by two main factors: the search for moisture and the availability of food. They require a high-humidity environment because their bodies lack the waxy cuticle that helps insects retain water, making them susceptible to drying out. Damp basements, crawl spaces, and bathrooms often provide the perfect humid refuge.
The presence of centipedes indicates a secondary pest problem within the home. They are actively hunting other common house pests, including spiders, silverfish, and ants, making them unintentional biological pest controllers. They enter through small cracks and openings in foundations, doors, and utility entry points while pursuing their prey.
Management should focus on making the indoor environment less hospitable. Reducing moisture is the most effective step, involving using dehumidifiers in damp areas and repairing leaky plumbing. Sealing entry points is also crucial, including caulking cracks in the foundation, around windows, and where pipes enter the wall. Removing their food source by controlling other household pests will discourage centipedes from taking up residence.