Mattila and colleagues, who spent hundreds of hours observing bees at a Vietnamese apiary, found that honeybees began adding feces to their hive entrances after natural attacks by giant hornets. By analyzing more than 300 filmed hornet attacks, the team determined that the hornets were less likely to linger at a hive entrance or initiate an invasion as the hive became more covered in feces.
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It’s unclear yet how exactly the fecal coating repels the hornets. It appears that the insects don’t like the smell, but they also may not want to chew into a nest covered in dung, a behavior that enlarges the hive opening for easier attack, Mattila says.
The feces may also function as a kind of olfactory camouflage.
Related:
Have you heard of the honey buzzard? If you haven't, you are in for a treat!
— Foxfeather Zenkova (@foxfeather) December 8, 2020
These raptors specialize in raiding wasp & bee nests, eating honey, larvae, and pollen.
Their head feathers have developed into hard, armor-like scales to protect them from stings.#birdtwitter pic.twitter.com/z8kDsLUhJM