Hornets are nasty predators that chop off the heads of honey bees before devouring them. They also feast on honey bee larvae. Bee stingers can’t penetrate the hornet’s body armor. But don’t think honeybees are defenseless.
Cyprian honeybees will swarm around a threatening hornet and form a tightly packed ball that kills the invader, according to a story in New Scientist by Roxanne Khamsi.
Scientists used to think the bee ball generated enough heat to kill the hornet. But a new study suggests the hornet inside the ball is suffocated. The hornet-destruction balls may be composed of as many as 300 bees, the story says, and pity the hornet—the execution by oxygen deprivation takes about an hour. It’s not clear how the bees coordinate their behavior to form the death ball, but bee researcher Alexandros Papachristoforou of Aristotle University of Thessaloniki in Greece thinks the bees might use chemical signals known as alarm pheromones to convene a gathering.
A National Geographic article "Hornets from Hell”
tells how just one Japanese giant hornet can dispatch 40 European honeybees in one minute, and a handful of them can slaughter 30,000 honeybees in a matter of hours. The Japanese giant hornet has venom powerful enough to "disintegrate human flesh,” the story says. But we also learn that hornets are extraordinarily good parents, who chew their prey into baby food for their larvae. And high-powered hornet saliva has been synthetically replicated in an energy drink popular in Japan. We say a dangerously angry person is "mad as a hornet." We say bees are industrious, but so are hornets. Do bees and hornets experience some mysterious elements of fear, glee or revenge in these life and death encounters? Will we ever know? We can only marvel at what scientists discover on how these amazing creatures with minuscule brains organize their lives, protect their own, coordinate their behavior, and survive in spite of relentless duties and random danger.