During the summer and fall seasons it is not uncommon for large groups of both wasps and bees to abandon their rural nests in order to swarm freely within residential and urban areas for a period of time before eventually establishing new, and usually hazardous, public nesting sites. New residential nesting sites often become established on trees, shrubs, home exteriors and even within obscured indoor areas, like wall-voids, attics and garages. As you can imagine, the urban and suburban presence of these free-swarming wasps and bees are threatening to residents since large groups of venomous insects are well known for inflicting fatal attacks on humans. However, wasps and bees only become dangerous when humans approach or make contact with active nests, so temporarily nomadic swarms are not often responsible for medically significant attack cases. Of course, these swarms do become aggressive once they establish a nesting site in a human-populated area. Understandably, the sudden and ominous presence of free-swarming social insects in populated areas are perplexing to at-risk residents, but there exists a perfectly sound reason as to why social insects relocate to human settlements during the summer and fall seasons.

Once the late summer and fall seasons arrive, honey bees can proliferate to the point where hives become too crowded. This can prompt a colony to split into two groups. One group remains within the hive, while the other is forced to search for a new nesting site. In order for the nomadic honey bees to survive outside of a hive, they must locate sustenance and adequate shelter rapidly. Since residential areas contain a diverse amount of garden flowers and plant nectar, as well as easily accessible nesting sites, like hollow trees and houses, wandering swarms are quick to establish new hives in residential locations. Once flowers become less abundant during the fall in the northeast US, robber bees and numerous wasp species often gravitate to residential areas in order to feed on human food sources within garbage bins, back porches and within homes. Garbage bins contain soda cans, and discarded food sources that provide bees and wasps with their last available food source for the year, and they are quick to build new nests in these areas. Once new nests are built on or within houses located near these food sources, the social insects become aggressive toward humans. This explains why wasp and bee attacks on humans become relatively frequent within neighborhoods during the late summer and fall seasons in the northeast and other temperate regions.

Have you ever heard a “buzzing” sound emanating from somewhere within your home?