Honey Bees Faithful to Their Flowers

MADISON, Wis. — Once a honey bee gives its heart to a flower patch it is far more faithful than the roving bumble bee. In fact, 76% of honey bees in a recent study revisited the same plot of alfalfa flowers in contrast to just 47% of eastern bumble bees.

The study conducted by U.S. Department of Agriculture Agricultural Research Service scientists, found that size does matter, at least to bumble bees. They were more faithful to larger flower patches, while the devoted honey bees are not concerned with size.

According to a press release from the USDA, to remain faithful to a specific location, an insect or animal requires reliable spatial memories enabling them to navigate complex landscapes and repeatedly return to the same site. 

Both bees, bumble and honey, have demonstrated this ability to return to previously visited foraging locations, leading the researchers to deduce there may be species-specific factors to explain the differing levels of fidelity.

In the release, the researchers say, differences in patch fidelity could be the result of bumble bees’ more explorative foraging behavior—their willingness to invest individually in foraging, often visiting more than one type of flower per foraging bout.

Honey bees’ on the other hand, have a more highly developed communication system—the honey bees’ well-known waggle dance. Honey bee foragers perform the dance when they return to the hive to share the location of valuable food sources with other foragers; bumble bees do not.

In more human terms, bumble bees are loyal loners while honey bees are sociable sharers.

“So higher patch fidelity of honey bees, relative to bumble bees, may reflect a greater aversion to risk, be it in terms of wasting energy and resources or encountering predators,” explained ecologist Johanne Brunet with the ARS Vegetable Crops Research Unit in Madison, Wisconsin, who led the study along with postdoctoral associate Fabiana Fragoso.

“The better our understanding of the characteristics that drive patch fidelity in important pollinators like honey bees and bumble bees, the better beekeepers, producers and conservation biologists will be able to support pollinators health as well as uphold the essential agricultural need to have crops pollinated to produce a harvest,” Brunet added.

This study was published in Ecosphere [https://doi.org/10.1002/ecs2.4606]