Honeybees depend on plant pollen as a protein-packed meals supply. And a few are even prepared to steal from different bees to get it.
Pollen stealing has been seen earlier than, in america. However now, researchers in Italy have additionally noticed honeybees snatching pollen off the backs of bumblebees. The observations, revealed December 21 in Apidologie, are among the many most in depth documentation of bee-on-bee larceny thus far.
On a summer time journey in 2019 to Mount Antola, within the northern Italian area of Liguria, unbiased naturalists Tiziano Londei and Giuliana Marzi, each based mostly in Milan, recorded video of what they thought had been honeybees (Apis mellifera) making an attempt to push bumblebees off the flower of a woolly thistle (Cirsium eriophorum). A better have a look at the video, nevertheless, revealed that this wasn’t a case of aggressive harassment — it was a full-blown theft.
As red-tailed bumblebees (Bombus lapidarius) scrounged across the flowers for nectar and pollen, some pollen grains caught to their bushy our bodies (SN: 9/6/17). Londei and Marzi witnessed honeybees shamelessly snagging this pollen for themselves. The thieves tended to focus on male bumblebees barely greater than females, because the males appeared much less bothered by the pilfering (although even females didn’t react aggressively).
“Honeybees are well-known as pollen pigs,” says Avery Russell, a biologist at Missouri State College in Springfield who was not concerned within the examine. So stealing pollen from the our bodies of bumblebees, he says, “doesn’t look like a far stretch.”
To see how widespread the criminality is, the researchers went again to the scene twice within the following three years and in addition noticed bees at two different websites about 25 kilometers away. Honeybees at these different websites weren’t seen stealing from bumblebees, however bees on the first website continued their larcenous methods yr after yr. As an illustration, honeybees collected pollen from solely three of the 31 flowers the researchers noticed in 2021, however stole from 28 of the accessible 66 bumblebees.
Scrutinizing the variations between these websites, the researchers suspect honeybees resort to theft in areas the place pollen is tough for them to get from flowers (the honeybees struggled to gather pollen from the woolly thistle), however the place there are many different bees round.
Pollen stealing by honeybees has beforehand been noticed solely in North America, first in Kansas after which later in California and Indiana. Discovering the conduct in Italy suggests this can be a worldwide crime spree. Russell says it could be good to subsequent study whether or not pollen theft negatively impacts bumblebees, or the flowers they pollinate. He’s additionally curious if different bee species ever steal pollen, too. “We do discover that within the hive, bumblebees will nibble on one another’s pollen baskets,” he says.
