The interaction between bees and wasps is a biological struggle characterized by rivalry and direct conflict. While both insects belong to the order Hymenoptera, they frequently occupy different ecological niches, leading to competitive or predatory encounters. Whether bees attack wasps depends entirely on the species involved and the immediate context, particularly whether the hive is being defended. Defensive behaviors range from passive avoidance to coordinated aggression against a persistent threat.
Wasp Predation and Hive Raiding
The primary context for conflict is the wasp acting as a predator, seeking out bees and their resources. Wasps, particularly social species like Yellowjackets and hornets, require protein to feed their developing larvae. Late summer and early autumn are periods of heightened aggression, as wasp colonies reach their peak population and their larvae demand more nourishment, driving adults to hunt for prey and sweet substances.
Predatory wasps scout bee colonies, often hovering near the hive entrance to ambush returning foragers. Larger species, such as some hornets, are capable of beheading a honeybee with their powerful mandibles, flying away with the protein-rich thorax to feed their young. These raids are not solely for protein; adult wasps also attempt to enter the hive to steal stored honey, a sugar source they need for energy.
These raids significantly damage the bee colony, depleting worker populations and losing valuable food stores. A sustained attack can weaken a colony to the point where it cannot survive the winter. Scout wasps that successfully enter a hive leave behind chemical markers, signaling to other wasps that the colony is vulnerable and ripe for invasion.
When Bees Become the Attacker
Bees actively attack wasps, but this aggression is exclusively a defensive measure carried out by specific members of the colony. The responsibility falls to the guard bees, typically older worker bees whose venom is at its maximum potency. These guards patrol the hive entrance, inspecting all incoming traffic to detect the specific colony odor of a potential intruder.
When a wasp is detected, the guard bees initiate a response that escalates quickly from a warning to a physical attack. They begin by releasing alarm pheromones to summon other guards and prime them for defense. If the wasp does not retreat, the guards engage in direct combat, attempting to bite the intruder with their mandibles and, as a last resort, using their stingers.
Stinging a wasp is a high-risk action for a honeybee, as the barbed stinger is designed to tear away from the bee’s abdomen, resulting in the bee’s death. This self-sacrifice prevents the invader from reaching the brood or honey stores. In some cases, a single wasp may be overwhelmed by a small group of guard bees who collectively sting and subdue the threat right at the hive’s threshold.
Specialized Hive Defense Tactics
Beyond individual combat, some bee species have evolved coordinated colony-level defenses against larger predators. One of the most remarkable is the “thermal balling” strategy, observed in bees like the Japanese honeybee against the Asian giant hornet. When a hornet approaches, hundreds of worker bees quickly swarm the intruder, forming a dense, vibrating ball around it.
The bees inside the ball rapidly vibrate their flight muscles, generating heat. This collective muscle activity raises the temperature at the core of the ball to approximately 46 degrees Celsius (115 degrees Fahrenheit). This temperature is lethal to the hornet, which has a lower heat tolerance.
This heat-based defense is coupled with other physical barriers employed by the colony. Bees strategically narrow the hive entrance using propolis, a resinous material collected from plants. This restricted opening makes it harder for a larger wasp or hornet to enter the hive, concentrating the defense where the guard bees can operate more effectively. This combination of physical restriction and coordinated thermal attack provides a highly effective, specialized defense.