There are several spider species that are well known for invading homes in the northeast US. These spider species include American house spiders, harvestman spiders, domestic house spiders, several wolf spider species, and in very rare cases, black widows. While these spiders are common household pests, they usually do not become abundant in homes, with the exception of harvestman spiders that invade basements and cellars in high numbers. These spiders are unlikely to bite a home’s human occupants, but this is not the case when it comes to another common house spider in the northeast, the yellow sac spider.

The yellow sac spider is found in homes frequently where they are often observed rapidly skittering across walls and even ceilings. This spider is also unique for being one of the few spiders that is considered aggressive toward humans, as they are not shy about making their presence known within a home. These bold spiders will even crawl onto humans within homes, often leading to unprovoked bites. The yellow sac spider is generally acknowledged as being responsible for the greatest number of spider bites when compared to all other spider species in the US, and they are the most likely culprits behind unidentified spider bites that are sustained within homes. This is due to the spider’s rapid movements, boldness and aggression, as these spiders are able to make a quick getaway after inflicting unprovoked and unanticipated bites.

These spiders can be recognized for their yellow exterior and they range is size from ¼ to ⅜ of an inch in body length. These spiders also possess relatively long legs, allowing them to travel rapidly. These spiders rely on their speed rather than webs for catching prey, and they can travel as rapidly as 3 feet per second. These spiders readily bite humans, but in some cases, their small fangs fail to puncture the skin. Bites are reported as triggering an immediate local burning sensation that can last for an hour or more, resulting in a rash or blister at the site of the bite wound. In rare cases, yellow sac spider bites result in medical complications, most notably tissue necrosis.

Have you ever spotted a yellow sac spider within your home?