Bees, recognized for their role as pollinators, contribute significantly to natural ecosystems and agricultural productivity. They facilitate the reproduction of numerous flowering plants, including many crops that sustain human populations. Despite their ecological importance, bees are subject to various natural threats from predators across different animal groups. This pressure from predators influences their behaviors and adaptations.
Insect Predators
Bees face numerous threats from other insects, which employ diverse hunting strategies. Wasps and hornets, such as the European hornet, are significant predators that frequently raid bee hives for adult bees and larvae. Hornets aggressively attack hives to feed their young, with some species, like the European hornet, carrying bees back to their nests. Certain predatory flies, including robber flies (also known as assassin flies), ambush bees in flight and inject them with enzymes to liquefy their insides, which they then consume.
Praying mantises are ambush predators that use their quick reflexes to capture bees mid-flight. Spiders, particularly crab spiders and jumping spiders, often lie in wait on flowers to ambush bees visiting for nectar or pollen. Dragonflies, known for their aerial agility, are also opportunistic predators that can snatch bees mid-flight. While dragonflies eat bees, they do not pose a significant threat to an entire colony unless present in very large numbers. Ants can enter hives to feed on honey and larvae, causing disturbance.
Vertebrate Predators
Larger animals, including mammals, birds, amphibians, and reptiles, also prey on bees, often targeting both individual bees and entire colonies.
Mammals
Bears, such as black bears and grizzly bears, raid beehives for protein-rich larvae and honey, often destroying hives. Raccoons also raid hives, particularly at night, tearing them apart to access honey and bees. Skunks visit bee colonies at night, scratching at hive entrances to lure out guard bees, which they consume. Honey badgers dig into hives to devour bees and honey.
Birds
Bee-eaters are specialized predators, catching bees and wasps in mid-air, often rubbing them against branches to remove stingers. Other birds, such as European honey buzzards, chickadees, woodpeckers, and swallows, also consume bees. European honey buzzards specifically hunt bees and wasps, using their talons to break into nests for larvae. Swallows and flycatchers catch bees as part of their diet.
Amphibians and Reptiles
Amphibians and reptiles also consume bees. Frogs are opportunistic feeders that eat bees, using their sticky tongues to capture them. While frogs can be stung, it does not deter them. Lizards, including skinks, are known to hunt and eat bees, though they usually do not significantly impact healthy bee populations.
Bee Defense Mechanisms
Bees have developed various defense mechanisms to protect themselves and their colonies from predators. Individual bees can use their stingers as a primary defense, injecting venom into a threat. Only female honeybees can sting, and while stinging a mammal often results in their death, this protects the colony.
Collective defense strategies are important for social bees. Guard bees patrol hive entrances, using scent and visual cues to identify intruders. If a threat is detected, guard bees release alarm pheromones, chemical signals that alert other bees and trigger a coordinated defensive response, mobilizing more bees to the entrance. This can lead to mass stinging or “balling” behavior, where bees form a tight cluster around a large intruder, such as a hornet, to immobilize and kill it. Asian honeybees (Apis cerana) have been observed applying animal feces around nest entrances to deter giant hornets. Some bee species, like giant honeybees (Apis dorsata), also perform “shimmering” waves across the comb surface, a synchronized movement that can deter visually-oriented predators.