We all have seen numerous movies set in the medieval times with castles in them. Little less known fact is that these castles had moats around them filled with water and feces. These feces were thrown out from the inhabitants living from behind the wall. Primary reason for it was lack of a sewage system. Mentioned excretions outside of castle walls would significantly lower persistence of enemy soldiers to conquer it, especially in summer. Air would simply stink too much! Last week scientists published their discovery claiming that Asian honeybees uses animal dung for the same purpose! Defense!! I always considered Apis cerana to be highly skilled in terms of battle in comparison to other honeybees.
Following a claim of a local beekeeper Heather Mattila decided to enter the chicken coop in rural area of Hanoi in Vietnam. This unusual method led to huge discovery for Mattila, and international team of researchers. They became very first scientists to document that honeybees forage for animal dung. Honeybees use the dung as a chemical weapon of sorts. They use it to defend their hives from giant hornet (Vespa soror) attacks. This directly means that honeybees are actually using a tool! A rather shocking discovery!
First Stages Of The Research
Mattila and her fellow researchers have studied interactions between giant hornets and Asian honeybees since 2013. They conducted their research at apiaries of local beekeepers on colonies which are inhabiting wooden hives.
First, the researchers wanted to confirm that the honeybees collect animal dung. Secondly, they set out to document and quantify how they used it and what effect it had. The team first visited local farmers to see if honeybees from the study apiaries were interested in their livestock’s waste. After some observation the team became convinced that honeybees were collecting animal dung from a chicken coop. So Mattila and her colleagues created a “dung buffet” beside a study apiary. Over the course of several days, the researchers paint-marked many bees while they were retrieving dung, then traced them back to their hives. To their surprise, honeybees were plastering the dung around their entrances.
Asian Honeybees Use Animal Dung For Defense
Researcher team from Vietnam in next stage of the research began tracking how the bees built up their defenses using feces. To their surprise, honeybees applied this strategy only as a response to attacks by giant hornets.
“Not only have we documented the first example of tool use by honey bees in nature,” Mattila said, “but the act of foraging for feces itself is another documented first for honey bees.” Honey bees routinely forage for materials produced by plants (such as nectar, pollen, and resin), but have not been known previously to collect solid materials from any other source. They occasionally collect fluids from animal waste, which can provide them with needed salts, but this is the first time they have been seen collecting solid pieces of dung, carrying it home with their mouthparts, and applying it to the entrance of their nests (called “fecal spotting”).
The preparation of defense (“fecal spotting”) usually continues for several days. Honeybees simply apply animal dung to the entrance of their hives. As a result, they effectively diminish severity of giant hornet attacks.
“We documented that hornets were less likely to land on entrances or chew their way into hives when there were more fecal spots around entrances,” Mattila said of their findings, which were recently published in the journal PLOS ONE, and covered in The New York Times and The Guardian.
“While further research is needed to determine exactly what properties of animal feces repels the hornets, the barrier the bees create is an effective defense against their attacks,” Mattila said. “What is also interesting is that the bees themselves are not repelled by the animal feces.”
The team found that honeybees also collected dung even if they had not yet been attacked but had been exposed to the chemicals released by hornet scouts and that Asian honey bees did not use this animal dung defense against smaller, less deadly hornet species. Important question remains. Did Asian honeybees use animal dung for defense always, or is this a new battle tactic? New discovery communicated between honeybees of different colonies?
You can read more news regarding honeybees and beekeeping here.