Who hasn't received a pot of homegrown honey from a friend or relative who decided to take up urban beekeeping? The sentiment behind the gift is sweet, but their newfound interest in urban agriculture may be adversely affecting local biodiversity.

 

In a new paper in the journal PeerJ, a team led by Concordia researchers argue that the rapid growth in urban honeybee-keeping over the past decade may be negatively impacting nearby wild bee populations. Small bees with limited foraging ranges may be especially at risk, they write.

 

The researchers compared bee population data collected from sites around the island of Montreal in 2013 to data they collected at the same sites in the summer of 2020.

 

"We found that the sites with the largest increase in honeybee populations across sites and years also had the fewest wild bee species," says Gail MacInnis, a former Concordia postdoctoral researcher and the study's lead author. Etienne Normandin from the Université de Montréal and Carly Ziter, an assistant professor in the Department of Biology, are co-authors.

 

According to Quebec's Ministère de l'Agriculture, des Pêcheries et de l'Alimentation (Ministry of Agriculture, Fisheries and Food), the number of honeybee colonies on the island of Montreal has increased over twelvefold. In 2013, there were under 250 colonies. That number has ballooned to almost 3,000 in 2020.

 

Honeybees are not native to the region, the researchers note. This type of bee is therefore in competition with almost 180 other species for resources like pollen and nectar, as identified in the 2013 study.