Honey bees and wasps often inhabit the same environments, but the presence of a honey bee colony does not deter wasps; it often attracts them. Wasps, particularly social species like hornets and yellow jackets, view the colony not as a threat but as a rich source of food. The relationship between these insects is antagonistic, characterized by predation and resource competition. This constant threat has driven the evolution of complex and sometimes bizarre defense strategies within the honey bee colony.
The Nature of the Bee-Wasp Conflict
The primary interaction between social wasps and honey bees is one of predator and prey. Wasps, unlike honey bees, acquire protein from animal sources to feed their developing larvae, and a bee colony offers a concentrated supply of this protein in the form of adult bees and brood. This predation intensifies during the late summer and autumn when natural nectar and prey insect populations diminish, making the colony’s stores and inhabitants a more appealing target. Social wasps, such as the German wasp and various hornet species, are the main threat. These species actively hunt and dismember bees, sometimes carrying the thorax back to their nest to feed their young. Solitary wasps generally pose less threat, focusing instead on paralyzing individual insects to provision their own nests.
Behavioral and Physical Defense Mechanisms
Honey bees have developed active defense behaviors to combat wasp and hornet attacks. The defense starts with specialized guard bees, which maintain vigilance at the hive entrance and recruit nestmates when a threat is detected. When a wasp approaches, these bees may release alarm pheromones, a chemical signal that quickly calls other bees to the entrance for collective defense. A highly specialized and dramatic defense is the formation of a “heat ball,” a tactic primarily used by Asian honey bee species against large hornets like the Japanese giant hornet. Dozens or even hundreds of worker bees will rapidly swarm the invading hornet, vibrating their flight muscles to generate heat.
Thermal Defense
This collective action raises the temperature inside the ball to lethal levels for the attacker, reaching an average of around 45°C (113°F). The hornet’s lethal temperature is approximately 44°C to 47°C, while the honey bees can tolerate slightly higher temperatures, up to 50.7°C for Asian bees. This gives the bees a narrow margin of safety. Physical stinging is also a direct defense mechanism, often targeting the hornet’s vulnerable neck-like region, the veracervix.
How Wasps Breach Honey Bee Colonies
Wasps employ specific, persistent hunting tactics that exploit the routine movements of honey bee foragers. The most common method, known as “hawking,” involves the wasp hovering directly in front of the hive entrance, establishing a hunting territory. The wasp attempts to snatch returning foragers, which are often slower and heavily laden with pollen or nectar, right out of the air. The sustained presence of hawking wasps creates immense stress on the colony and can paralyze foraging activity. Bees become reluctant to leave the safety of the hive, which depletes the colony’s workforce. This is particularly damaging in late summer when the colony needs to store resources for winter.
Mass Attacks
In severe cases, hornets like the Asian giant hornet can launch coordinated mass attacks after an initial scout marks the hive. These attacks can result in the complete slaughter of the adult bee population within a few hours to gain access to the protein-rich brood. Colonies that are already weak or small are especially vulnerable to these invasions, as their defense force is insufficient to repel the sustained assault.