A decade of bumble bee surveys: Part 1 – Who, when, where, how?
Posted onJanuary 17, 2023by|, , ,
A decade ago, Wildlife Preservation Canada (WPC) initiated their Bumble Bee Recovery Program. Through conservation breeding, annual large-scale population surveys, community science, engaging in education and outreach, and collaborating on important research, WPC is a leader in bumble bee conservation. With several of our North American species assessed to be in decline, it’s critical that we monitor our species.
Are you curious what has come from a decade of bumble bee population surveys in Ontario? Here is the first part in a four part series focusing on the species we’ve observed.
Some of the species observed over the years. Photos: T. Harrison. Left to right: yellow bumble bee (Bombus fervidus), brown-belted bumble bee (B. griseocollis), tri-coloured bumble bee (B. ternarius), black-tailed bumble bee (B. melanopygus), yellow-banded bumble bee (B. terricola), American bumble bee (B. pensylvanicus), northern amber bumble bee (B. borealis), red-belted bumble bee (B. rufocinctus), lemon cuckoo bumble bee (B. citrinus)
Over the years our team has scavenged the province, surveying nearly 500 different sites across Ontario (most concentrated in south-central Ontario), searching for as many bumble bees we can find. Where have we looked for bumble bees you ask? We have visited many different types of sites, for example provincial and national parks, conservation areas, city parks, and even roadsides that have suitable bumble bee habitats (e.g., lots of flowers!). We primarily conduct surveys in the early spring as queens emerge from overwintering – allowing us to collect wild queens for our conservation breeding program before they initiate colonies in the wild.
With crews stationed in city hubs like Guelph, Huntsville, Sudbury, and Thunder Bay –we conduct timed, catch and release netting surveys (non-lethal), where we canvas sites as a team to see who we can observe. We try to visit as many sites as we can throughout the season, collecting candidates for our breeding program (mainly Special Concern yellow-banded bumble bees, B. terricola), and trying to locate rare and at-risk species.
Site map for bumble bee population surveys (2013-2022).
Through our intensive survey effort (investing over 1600 hours!), we’ve been able to record over 26,000 individuals and observe 20 species! (Curious which? See the table at the end, with the years they have been observed).
Over the decade, we have been able to observe some interesting species, including three which are currently assessed to be in decline:
The common eastern bumble bee (B. impatiens) does live up to its name, being the most common after all. Making up about 30% of all bumble bees we’ve seen over the years (nearly 8000 records!), without a doubt it’s our most observed species. Another significant portion of our records go to the tri-coloured bumble bee (B. ternarius) and the two-spotted bumble bee (B. bimaculatus).
There are two species we found in their native range of Ontario, which we’ve only observed in just a single survey year:
In addition to those species above, we’ve also been able to observe some rare or fairly uncommon species in these regions such as the Fernald’s cuckoo bumble bee (B. flavidus) and the frigid bumble bee (B. frigidus).
Note: observations for the Sanderson’s bumble bee (B. sandersoni) are tentative for some years due to the difficulty in identifying the species in the field as it resembles multiple other species, and no surveys were conducted in 2020 due to the COVID-19 pandemic.
We want to thank everyone who has helped contribute to WPC’s annual bumble bee surveys, we couldn’t have done it without you! What will we find over the next decade?
Tiffani and Parker surveying at rare Charitable Research Reserve. Photo: S. Knoerr
This installment of the series discussed the species we have observed. Click here for Part 2, where we discuss the floral resources we have recorded bumble bees using.