New research finds urban environments maybe contributing to decline in female bee populations

Mar 13, 2019

New research out of the University of Michigan sheds light on how cities are impacting population declines in ground-nesting bees.

Researchers captured over three thousand bees across five cities in Southeast Michigan and found that declines in ground-nesting bees were largely driven by a drop in female bee numbers.

Dr. Paul Glaum is a researcher on the study. He said the drop in female bees could be caused by fewer places for nests in an urban environment.

“Trying to find a way to preserve or promote at least some ground-nesting space for these bees will likely be the component of a bee-friendly city.”

Glaum said ground-nesting bees are the largest subset of bee populations.

“So it’s a worry from a population maintenance standpoint. It’s also a worry considering the different pollination services that these bees offer.

Male and female bees pollinate different flowers.

Glaum said protecting bee species in the long term will likely involve some kind of urban planning making more space for bee nests.

He said another bee species - the cavity-nesting bee - actually saw population increases in an urban environment.