Certain honeybees in Italy routinely engage in the act of pilfering pollen from the bodies of bumblebees.
Honeybees heavily rely on plant pollen as a protein-rich food source, and some are even resorting to thievery from other bees to obtain it.
Honeybees
While pollen stealing has been observed in the United States, researchers in Italy have now documented honeybees pilfering pollen from the backs of bumblebees. The extensive observations, published on December 21 in Apidologie, provide valuable insights into bee-on-bee larceny.
During a summer expedition in 2019 to Mount Antola in the northern Italian region of Liguria, independent naturalists Tiziano Londei and Giuliana Marzi, both based in Milan, captured video footage of what initially appeared to be honeybees (Apis mellifera) attempting to displace bumblebees from the flowers of a woolly thistle (Cirsium eriophorum). Upon closer examination, it became clear that this behavior was not mere competitive harassment but an outright robbery.
As red-tailed bumblebees (Bombus lapidarius) foraged for nectar and pollen on the flowers, honeybees shamelessly snatched pollen grains stuck to their hairy bodies. The thieves exhibited a preference for male bumblebees, who seemed less bothered by the pilfering, although even females did not react aggressively.
Avery Russell, a biologist at Missouri State University in Springfield, notes that honeybees are known as “pollen pigs,” making the act of stealing pollen from bumblebees unsurprising.
To assess the prevalence of this behavior, the researchers revisited the site twice over the following three years and observed bees at two additional locations approximately 25 kilometers away. While honeybees at the other sites did not engage in stealing from bumblebees, those at the initial site persisted in their larcenous activities year after year. The researchers speculate that honeybees resort to theft in areas where collecting pollen from flowers is challenging for them, especially if there are plenty of other bees present.
Previously, pollen stealing by honeybees had only been documented in North America, specifically in Kansas, California, and Indiana. The discovery of this behavior in Italy suggests that it may be a global phenomenon. Russell expresses interest in understanding whether pollen theft has negative consequences for bumblebees or the flowers they pollinate. Additionally, he wonders if other bee species also engage in pollen theft, citing observations of bumblebees nibbling on each other’s pollen baskets within the hive.
