Wild bees thrive among diverse flower communities, Concordia study shows

by Patrick Lejtenyi, Concordia University
March 11, 2025

Spring is approaching — really! — and with it come the perennial considerations about which kinds of flowers to plant and where. These questions go far beyond mere aesthetics: flowers are an essential source of food for birds and insects, including the dozens upon dozens of species of wild bees found in most cities. For them, what’s on the menu is a matter of life or death.

The relationship between flower species and pollinator populations matters deeply to urban biodiversity. In a study published in the journal Ecological Applications, Concordia researchers look at how certain floral characteristics interplay with urban bee populations.

They found that a diversity of size and shape of the corolla — the tube-like structure formed by a ring of petals around the flower’s centre, where nectar is typically stored — in the urban flower community has a positive relationship with wild bee biodiversity. The more diverse the urban flower population, the richer the wild bee population.

“We know that flowers are an important source of nutrition for bees, but not all flowers are created equal,” says the study’s corresponding author Carly Ziter, an associate professor in the Department of Biology in the Faculty of Arts and Science.

“Having a high diversity of flowers is a key to supporting bee populations, but our research goes one step further to show a possible mechanism: that having a diversity of floral species is important because they have different shapes and sizes.

“This follows the idea of size-matching, where corollas are the right size for a certain type of bee’s proboscis or tongue, allowing it to effectively connect to the flower’s nectar. So, whether a bee has a short or longer proboscis, they will be able to access the nutrition they need if there are multiple kinds of flower morphology nearby.”

Keep reading: https://www.concordia.ca/news/stories/2025/03/11/wild-bees-thrive-among-diverse-flower-communities-concordia-study-shows.html

Read the Ecological Applications paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.3067