Social hornet species, such as the European hornet (Vespa crabro) and the Asian giant hornet (Vespa mandarinia), do have a queen. This reproductive female is the founder and sole progenitor of the colony. Her presence defines the colony’s structure and ensures its growth and survival through the annual cycle.
The Essential Role of the Queen Hornet
The primary function of the queen hornet is reproduction, acting as the sole female capable of laying eggs and generating all the workers, drones, and future queens. This reproductive monopoly is supported by her ability to control the sex of her offspring through fertilization.
The queen stores sperm from her mating flight in a specialized organ called the spermatheca, allowing her to fertilize eggs. Fertilized eggs contain two sets of chromosomes, developing into female individuals that become the sterile workers maintaining the nest. Conversely, unfertilized eggs contain only one set of chromosomes and develop into males, known as drones.
The queen also exerts significant control over the colony’s behavior and the workers’ sterility through the release of chemical signals called pheromones. These pheromones communicate her reproductive status, suppressing the workers’ ability to lay eggs and keeping them focused on foraging and nest maintenance.
Without the queen, the colony cannot sustain itself, and its population will steadily decline once the current generation of workers reaches the end of their lifespan. If the queen is lost early in the season, the colony’s growth ceases, and it will eventually collapse. In some cases, a worker may begin laying unfertilized eggs, which only produce males, but this does not save the colony from demise.
The Queen’s Annual Lifecycle
The life of a hornet queen is synchronized with the seasons, beginning when a newly mated female overwinters in a state of dormancy, known as diapause. She seeks sheltered locations, such as tree hollows or protected cavities, to survive until early spring.
Once the ambient temperature is suitable, the queen begins the “Founding Phase” of the colony entirely alone. She searches for a suitable nesting site and constructs a small, embryonic nest from chewed wood pulp, creating the first few cells for her initial batch of eggs. During this solo phase, she must forage for food, feed the developing larvae, and defend the nascent nest.
After approximately four to six weeks, the first generation of female workers emerges, marking a significant turning point. The new workers immediately take over all duties outside the nest, including foraging and expanding the nest. This shift allows the queen to remain deep within the nest, maximizing reproductive output throughout the summer.
In late summer or early autumn, the queen changes the composition of her eggs, producing males and a final generation of reproductive females that will become the next year’s queens. These new, fertile females and the males leave the nest to mate. After mating, the males die, and the newly fertilized females seek places to hibernate. The original founding queen, having completed her one-year cycle, dies as the weather turns cold.
Identifying the Queen: Distinguishing Her from Workers and Drones
The most reliable way to distinguish a queen hornet from the other castes is by her size; queens are significantly larger than workers and drones. For example, a European hornet queen can measure up to 1.5 inches in length. This difference in size is most apparent in the abdomen, which is long, robust, and swollen compared to the workers’ more slender midsections.
Behavioral differences also provide a clue. Once the first workers emerge, the queen rarely leaves the protection of the nest, spending all her time laying eggs in the brood cells. Workers, conversely, are the ones actively flying in and out of the nest entrance, foraging for food and building materials.
The males, or drones, tend to appear later in the season. Drones are generally smaller than the queen but can be stouter than workers, with a noticeably thicker body and larger eyes. Crucially, drones lack a stinger.
Telling the difference between a particularly large worker and a queen can be difficult without direct comparison, especially during the founding phase when the queen is still performing all the foraging duties. A hornet found outside the nest during the peak summer months is almost certainly a worker.