Certain wasp species are predators of honey bees, actively hunting them as a food source. This article explores the dynamics of this interaction, detailing the wasp species involved, their hunting strategies, and the defense mechanisms honey bees employ.
Key Wasp Species That Prey on Honey Bees
Several wasp species prey on honey bees, with their predatory impact varying by region. The European hornet (Vespa crabro) is a prominent predator in Europe and North America, often found near bee hives. These large wasps capture individual worker bees, especially those returning with pollen or nectar.
Yellowjackets (Vespula and Dolichovespula) are also common honey bee predators. These smaller, agile wasps often attempt to enter hives to steal honey or prey on bees. Their aggressive nature and numbers can pose a challenge to colonies, particularly when yellowjacket populations peak in late summer and autumn.
The Asian giant hornet (Vespa mandarinia), though less widespread, is known for its ability to decimate honey bee colonies. Where present, these exceptionally large hornets launch coordinated attacks, killing adult bees to access brood and honey. Their presence can severely impact local bee populations, especially European honey bee subspecies, which lack evolved defenses.
How Wasps Hunt Honey Bees
Wasp hunting strategies for honey bees vary by species and environment. European hornets patrol hive entrances, ambushing bees flying in or out, or target foraging bees away from the colony. Once caught, the hornet dismembers the bee, taking only the protein-rich thorax back to its nest for larvae. This process ensures efficient transport of nutrients for the wasp’s developing young.
Yellowjackets, being smaller, employ different tactics, including attempting to enter hives to scavenge or prey on bees inside. They may also wait near water sources or flowers where bees forage, snatching them mid-flight. The captured bee is then chewed into a manageable piece before being carried back to the yellowjacket nest to nourish growing larvae.
Asian giant hornets engage in organized hunting, particularly during their “slaughter phase.” A scout hornet locates a colony and marks it with a pheromone, attracting nest mates. A group of hornets then attacks the hive, killing adult bees, often by decapitation, to access the bee larvae and pupae inside, which they then transport back to their own colony.
Honey Bee Strategies for Survival
Honey bees have developed various strategies to defend against wasp predation, ranging from individual actions to coordinated colony-wide responses. Guard bees are stationed at the hive entrance, acting as sentinels to detect and intercept invading wasps. These guards engage in direct combat, using their stingers to deter or kill smaller wasps. If a wasp breaches initial defenses, alarm pheromones are released, alerting other bees.
One defense mechanism is “balling,” where many honey bees surround an invading wasp, forming a tight sphere. Within this ball, bees vibrate their flight muscles, generating heat, sometimes reaching temperatures of 45-47 degrees Celsius (113-117 degrees Fahrenheit). This heat, combined with elevated carbon dioxide levels, can overheat and kill the wasp without harming the bees themselves. This strategy is effective against larger predators like hornets.
Some honey bee subspecies, such as the Asian honey bee (Apis cerana), have evolved specific defenses against Asian giant hornets. They coat the entrance of their nests with animal feces, creating a “fecal spot” that repels hornets. Honey bee colonies may also alter their foraging patterns, reducing activity during peak wasp predation times to minimize exposure to predators.
Broader Ecological Role and Impact on Colonies
Wasps, including those that prey on honey bees, play a role as generalist predators within their ecosystems. They contribute to the regulation of insect populations, feeding on a variety of arthropods, including other pests.
For healthy, established honey bee colonies, the typical level of wasp predation is often manageable. Strong colonies with large populations can usually withstand the loss of some worker bees without significant long-term impact on their overall health or productivity. The colony’s inherent defensive mechanisms and reproductive capacity allow it to absorb these losses.
However, the impact can be more pronounced on stressed or weakened honey bee colonies. Factors such as disease, pesticide exposure, or resource scarcity can compromise a colony’s ability to mount effective defenses against wasp attacks. In such cases, persistent wasp predation can exacerbate the colony’s decline, potentially leading to its collapse. This highlights how the balance between predator and prey is influenced by the overall health of the prey population.