Bumble bees are familiar, fuzzy insects, often mistaken for their more aggressive cousins. They primarily utilize a stinger for defense when they feel threatened, which is their most significant mechanism for injecting venom. However, like all bees, they possess strong mandibles, or jaws, which they use for functional tasks, meaning they can technically “bite.”
The Primary Defense Mechanism
Only female bumble bees, specifically the workers and the queens, possess the ability to sting. This defensive structure evolved from the female egg-laying organ, known as the ovipositor, which is why male bees, called drones, lack a stinger and are incapable of stinging. Bumble bees are generally docile and typically sting only as a last resort to protect themselves or their nest.
Their stinging apparatus is designed for repeated use. The bumble bee stinger is smooth, allowing the insect to easily withdraw it from the skin after injecting venom. This means a single bumble bee can deliver multiple stings if provoked severely or if the nest is disturbed. The venom causes immediate, sharp pain and initiates a localized reaction, including swelling and redness.
The Role of Mandibles
Bumble bees have a pair of powerful mandibles, essentially tiny jaws, which they use for activities essential to their survival and colony maintenance. These mandibles are primarily tools for construction and manipulation, not for large-scale defense. They use them to chew pollen and nectar, shape wax cells, and excavate tunnels where their colony is located.
One interesting use of their mandibles is in “nectar robbing,” where they pierce a hole at the base of a flower to access nectar without crawling inside. Research has also shown they may bite plant leaves when pollen is scarce, which encourages the plant to flower earlier. If a bumble bee uses its mandibles on human skin, it results in a non-venomous pinch and rarely breaks the surface.
Key Differences from Honey Bees
The primary physical difference in defense between a bumble bee and a honey bee lies in the structure of their stinger. The bumble bee has a smooth, needle-like stinger that allows it to retract the organ from the skin without causing internal damage to itself. This reusability is what permits the insect to sting multiple times throughout its life.
In contrast, the stinger of a honey bee worker is barbed, or jagged, which anchors the stinger securely into the skin of a mammal. When the honey bee attempts to fly away, the entire stinging apparatus, including the venom sac and part of its abdomen, is ripped from its body, resulting in the bee’s death shortly after a single sting. The bumble bee’s ability to survive a sting is a factor in its less aggressive temperament.
Prevention and Immediate Action
The most effective way to prevent a sting is to simply leave bumble bees undisturbed, particularly near their nests, which are often hidden in the ground or in dense patches of grass. If a bumble bee approaches, remain calm and avoid swatting or making sudden movements, as this can be perceived as a threat. They are focused on foraging and will typically move away quickly if they do not feel provoked.
If a sting occurs, the immediate action is to clean the affected area thoroughly with soap and water to prevent infection. Since the stinger is smooth, it is rarely left embedded in the skin. A cold compress applied to the site will help reduce both the swelling and the burning sensation. It is important to monitor for signs of a severe allergic reaction, such as difficulty breathing or swelling away from the sting site, and seek emergency medical attention if those symptoms appear.