A new study of native bumblebee populations in southeastern Michigan cities found, surprisingly, that Detroit has more of the large-bodied bees than some surrounding, less urbanized locations.

The University of Michigan students who conducted the study suspect that the large amount of vacant or idle land in Detroit may boost the bumblebee population by providing nesting sites and flowers for food.

Bumbleebees belong to the bee genus Bombus. In the study, more than 500 individuals from 10 species were identified at 30 sites in southeast Michigan.

"Sites within Detroit had higher Bombus abundance and diversity, despite their location in the densest urban landscape," according to the authors—four U-M graduate students and one undergraduate—of a study published online May 17 in the journal Royal Society Open Science. "Overall, these results have important implications for conservation of native bee populations and pollination services."

Native bees are critical sources of pollination for agriculture and wild flowering plants. Many native bees are declining in both abundance and diversity, due to various causes that likely include loss of habitat from human activities. While the effects of large-scale agriculture on native bees are relatively well understood, the effects of urban development are less clear.

To help clarify the role of urbanization, the U-M researchers sampled bumblebees at nature reserves and urban farms and gardens in several southeast Michigan cities—Dexter, Ann Arbor, Ypsilanti, Dearborn and Detroit—with varying degrees of urban development. Each city has a dense urban core surrounded by suburban development.

The authors of the Royal Society Open Science paper are graduate students Paul Glaum (first author), Chatura Vaidya and Gordon Fitch of the Department of Ecology and Evolutionary Biology; graduate student Maria-Carolina Simao of the School of Natural Resources and Environment; and undergraduate Benjamin Iulinao of the Department of Ecology and Evolutionary Biology.

Read full Michigan News press release

The story is receiving widespread media attention including these stories in Anthropocene and in U.S. News & World Report. A WDET-FM public radio story is forthcoming as well as stories in The Scientist magazine and Metro Times.