Feral Honey Bees in Urban Environments

 

Above: Exterior view showing the window shutter from outside.
Below: Interior view of the window shutter box with the access panel removed.

Introduction to the Citizen Science Article Earlier this year, I uploaded a photo of a local Atlanta bee nest entrance—found in a cut-off sycamore limb—to the Free Living Bees website. Not long after, I came across a fascinating citizen science journal article featured on the same site. As someone obsessed with swarms, I found it absolutely captivating.

Urban Population Density The research focuses on the city of Belgrade, Serbia—a large and densely populated urban environment. Residents reported both honey bee nests and swarms, often seeking help with their removal. Interestingly, the number of reports increased exponentially with population density (a relationship shown clearly in the paper’s data).  To verify and expand on these reports, the authors conducted phone interviews with the residents and followed up with on-site field studies.

Reported Swarms vs. Nests At first, I assumed that reports of swarms and nests would occur in roughly equal numbers—but not so. The study found 261 swarms compared to only 90 nests, meaning swarms were reported nearly three times more often.  Most swarms (about 78%) were seen at heights between 1–9 meters, remarkably similar to what Seeley describes in Honeybee Democracy (p. 52). Reported nest heights, on the other hand, were concentrated between 3–15 meters (about 74% of cases).

Interior–Exterior Shutter System Jovana Bila Dubaić kindly sent me photos to help clarify the distinction between (1) the wooden window shutter and (2) the wooden window shutter box. Many buildings in Belgrade feature a combined interior–exterior shutter system.
When closed, pedestrians see the wooden window shutter covering the exterior. When retracted, however, the shutter rolls upward into a wooden box located inside the building, above the window. Astonishingly, 30.7% of reported nests were found inside these shutter boxes.

Exploring with Google Street View Curious, I used Google Street View to explore some of Belgrade’s most populated neighborhoods—imagining myself as a scout bee. What I “saw” was extraordinary: street after street lined with windows that offer easy access to those wooden shutter boxes. From a bee’s perspective, it’s a smorgasbord of indoor nesting opportunities.

In summary Don’t be intimidated by the lengthy title: “Unprecedented Density and Persistence of Feral Honey Bees in Urban Environments of a Large SE-European City.” The paper is well worth the read, and if you reach out with questions, you’ll likely find that the lead author, Jovana Bila Dubaić, is remarkably generous with her responses.