What are hornets scared of?

What hornets are scared of includes natural predators, strong smells, and threats that make them defensive, though they are not easily scared away from nest when defending colony. Natural predators that scare hornets include birds like bee eaters, honey buzzards, and swallows that catch hornets in flight and eat them, often removing stinger, and mammals like badgers and bears that raid nests for larvae, which scares hornets as they try to defend but are overpowered, and insects like dragonflies, robber flies, and praying mantises that prey on hornets. Hornets are scared of strong smells like peppermint oil, eucalyptus oil, citronella, and clove oil that can be used as deterrents, though evidence limited. They are scared of loud vibrations and disturbances near nest that signal predator, causing them to become defensive rather than flee. Hornets are scared of fake hornet nests, as they are territorial and may avoid areas where they think another colony exists, so hanging decoy nests may deter new colonies, though effectiveness mixed. They are scared of lack of food in early spring and late fall when resources scarce. For humans, most effective scare is removing attractants like covering food and sealing trash, and professional pest control removal that eliminates colony, as hornets defend nest vigorously and are not easily scared away when colony threatened, so prevention and professional removal are better than trying to scare them away with DIY methods that can provoke attack.