An ‘American bumble bee’ (Bombus pensylvanicus) queen. Photo: T. Harrison.

Buzzworthy pursuits: Finding rare and at-risk bumble bee species in Ontario.

Posted onSeptember 19, 2023byCole Blair|Bumble Bees, News and Events, Pollinators

What is the Bumble Bee Recovery Program? Since the 1990s, bumble bee numbers have been plummeting, and that spells ecological disaster. Ninety per cent of all flowering plants — including most of the fruits and vegetables in your fridge — need these pollinators in order to reproduce.

Until the causes of these declines can be reversed, conservation breeding and reintroduction is the only way to safeguard at-risk bumble bees. Today, WPC is the only organization in Canada rebuilding wild bee populations through conservation breeding. Thanks to recent breakthroughs, we’ve figured out how to dramatically increase the number of queens we produce. Once they’re released into the wild, they can establish their own colonies, producing hundreds of pollinators to sustain the ecosystems around them.

Within the bee world, the most well-known species is undoubtedly the European honey bee (Apis mellifera). However, many aspects of our terrestrial ecosystems – namely the pollination of wild and agricultural plants – rely on the humble bumble bee (genus Bombus). To combat the unfortunate decline of our vital native bumble bee species, Wildlife Preservation Canada’s Native Pollinator Initiative implements a variety of conservation techniques that require on-the-ground fieldwork.

Conservation breeding is a crucial component in understanding species-at-risk and boosting their populations, and is also a technique we focus on with the ‘Special Concern’ yellow-banded bumble bee (Bombus terricola) (you can learn more about our bumble bee breeding lab here). Of course, our breeding efforts can’t begin if we don’t have bees in the lab, so capturing yellow-banded bumble bee queens is one of our top priorities during spring surveys!

Left: Fernald’s cuckoo bumble bee (B. flavidus) female. Right: yellow bumble bee (B. fervidus) worker. Cooling the bees or observing from within vials helps us identify tricky species! Photos: C. Blair.

Finding these bees also serves as a reward for our hardworking field teams and I speak from firsthand experience! In the 2023 field season, our two field teams, operating out of Guelph and Sudbury, captured and identified a combined 59 bumble bees belonging to species that are either at-risk or are known to be rare. Of these, 43 were yellow-banded, which is unsurprising since we often pick sites where this species has been recorded, and 4 were American bumble bees (B. pensylvanicus) – a species also listed as ‘Special Concern’.

We also identified a handful of other bumble bees that, while not having a dire conservation status, are evidenced to be experiencing declines in Canada or are otherwise rare: 2 yellow bumble bees (B. fervidus), 1 frigid bumble bee (B. frigidus), 5 black and gold bumble bees (B. auricomus), 2 Fernald’s cuckoo bumble bees (B. flavidus), and 2 lemon cuckoo bumble bees (B. citrinus).

Finding these species requires thoughtful planning and a healthy dose of luck. Some of my favorite fieldwork experiences are surveying a new site for the first time and capturing one or more of these bumble bees. In 2022, for example, the Guelph team ventured into Toronto and surveyed at a local park complex, where black and gold bumble bees (B. auricomus) were first recorded in a WPC survey! We re-visited that same park in 2023 and were able to find them once again (this is the only site where we’ve found them). Needless to say, I am eager to go back in spring 2024 and find more!

Black and gold bumble bee (B. auricomus) queens. A species dear to my heart! Photo: T. Harrison.

Cole Blair

Ontario Program Coordinator – Native Pollinator Initiative

Cole’s time with WPC began as a graduate student at the University of Toronto, where he researched harmful parasites in bumble bees (he looked at a LOT of bee poop). He has since played a supporting role as a technician in both the field and in our bumble bee Conservation Breeding Lab. As the Ontario Program Coordinator, Cole hopes to demonstrate to others that any conservation engagement – no matter how big or small – can go a long way.