A day in the life of endangered bumble conservation: Carpenter bees are not bumble bees!

Posted onAugust 15, 2024byBraelyn Smallwood|Bumble Bee Recovery, Native Pollinator Initiative, News and Events

Photo above: Wildlife Preservation Canada’s Southern Ontario bumble bee field team after a successful survey! From left to right: Braelyn Smallwood, Dana Stubbs, and Cole Blair. Photo by Cole Blair.

University of Guelph Master of Wildlife Biology Student Braelyn Smallwood spent her summer with Wildlife Preservation Canada’s Native Pollinator Initiative, as a part of the program’s hands-on training and skill development. WPC provides opportunities for Canadian biologists to increase their expertise, helping to build this country’s conservation capacity, and is excited to provide a space for these students.

I had the opportunity to volunteer as a Bumble Bee Conservation Technician with Wildlife Preservation Canada to monitor bumble bee populations in southern Ontario and collect species-at-risk bumble bees for conservation breeding. A typical day in this role involved completing three-hour surveys which included catching bumble bees with a sweep net, placing them in a vial, and noting species identification on the vial. It was also important to take note of the variety of flowers in bloom within the survey area and any flowers that the bumble bees were caught on. Roughly two surveys were completed each workday on sunny, warm days which is when bumble bees are most active. Some key skills gained through this role were spotting bumble bees and with bumble bee and wildflower identification.

During my first week of volunteering with WPC I learned how to locate and capture bumble bees! (Images below: Braelyn uses a bug net to gently catch the bumble bee, and place it in the vial).

2024_Bumble_Braelyn surveying(UofG volunteer)_Dana Stubbs

2024_Bumble_Braelyn surveying(UofG volunteer)_Dana Stubbs(3)

2024_Bumble_Braelyn vialing(UofG volunteer)_Dana Stubbs

2024_Bumble_Braelyn with vial(UofG volunteer)_Dana Stubbs

I was given a sweep net with a long, telescopic handle, as well as a cooler bag full of empty vials and an ice pack. My job was to catch all the bumble bees I found, place them in a vial for easier identification, and keep them calm and comfortable in my cooler bag until the end of the three-hour survey when we would release them. Sounds simple, right?

But what I didn’t know was how closely some things looked like bumble bees. I began my first survey excitedly, ready to fill my bag full of vials with bumble bees, however I realized I was not finding them as quickly as I had hoped! Was I not looking in the correct habitats? Did the bumble bees prefer different flowers elsewhere? I didn’t know. As I continued my search, I came across a big bee that was yellow and black. I couldn’t believe that my luck had changed, and I was going to catch my first bumble bee! I swung my net back and forth a few times before the bee was caught.

I was ecstatic to have caught my first bee of the day! Joyfully, I stored the filled vial in my cooler bag, excited for all bumble bees to come.

I continued with the rest of the survey and caught only a handful of bees. I felt that since I was still learning, this was sure to impress the program coordinator. As the bees were separated into categories of what behavior they were exhibiting before being caught, I eagerly brought my bees out to start sorting. I still required some assistance with bumble bee identification and handed off each of my bees to the coordinator.

I was shocked to find out that not all the bees I collected were bumble bees!

As I took a closer look, I realized that some of my bumble bees were instead carpenter bees (Xylocopa virginica)! Carpenter bees are not a type of bumble bee (genus Bombus) which meant that, in my first survey, I caught fewer bumble bees than I had thought. With this realization, I quickly learned to watch for the identification markers before catching a big, black and yellow bee.

So what identification markers am I looking for?

During a survey, when bees are darting around flowers looking for pollen and nectar, it can be difficult to know exactly what I’m looking at before I capture it. Carpenter bees and bumble bees are both native to Ontario, and to the untrained eye, one can look like the other. Carpenter bees, like bumble bees, have hairs on their face, a thorax covered in dense yellow hairs, and hairy legs. However, carpenter bees have a smooth, bald abdomen (the long part of the body towards their rear), while most bumble bees have hairs of various colors on their abdomen. Bumble bees can possess a combination of black, yellow, white, red, or brown hairs on the different segments of their abdomen, but again, a carpenter’s abdomen would appear shiny due to the lack of hairs!

An eastern carpenter bee (Xylocopa virginica) (left: photo by akiyoko on iStock) and a common eastern bumble bee (Bombus impatiens) (right: photo by Braelyn Smallwood). Note the hairy thoraxes (the body segment between the head and the abdomen) and legs on both individuals. Contrast the shiny, hairless abdomen of the carpenter bee with the hairy abdomen of the bumble bee.

This all seems simple, right? I just have to watch for the shiny behinds of carpenter bees and leave them be, focusing solely on the bumble bees that we are monitoring in the field.

It was easy enough until I learned that there are some bumble bees that have fewer hairs on their abdomens, almost like a carpenter bee! The lemon cuckoo bumble bee (Bombus citrinus) in particular can look a little suspicious at first glance. This is due to lemon cuckoo bumble bees having much shorter hairs on the abdomen than most other bumble bees. This creates a bit of an illusion where sunlight shines through and creates a gleam on their abdomen like what we’d see on a carpenter bee.

A lemon cuckoo bumble bee (Bombus citrinus) female foraging from a daisy! Note the shiny gleam on the abdomen in the left photo. Looks much different from the densely hairy abdomen of the common eastern bumble bee we looked at earlier, right? The angle in the right photograph further displays just how short these abdominal hairs are on this species. Photos by Braelyn Smallwood.

This serves as a notice that there are always exceptions to every rule in nature!

We can summarize the differences between carpenter bees and bumble bees by the shiny and hairy abdomens on either kind, respectively, however the lemon cuckoo bumble bee has shown me that this is not the case for every species of bumble bee! With this in mind, we should all remind ourselves that something may not always be what we think it is.

The skills I have learned in this role allow me to confidently survey for bumble bees while recognizing the difference between these bees and other bee species we see in the field! This experience has helped me to discover my love for working outdoors and conducting surveys.

Braelyn Smallwood

Bumble Bee Conservation Technician – Native Pollinator Initiative

Braelyn volunteered as a Bumble Bee Conservation Technician to assist in our survey and research efforts in Southern Ontario. She is currently finishing her master’s degree in wildlife biology at the University of Guelph. Braelyn plans to help improve wildlife populations and their habitats through scientific research and ecosystem restoration