A Deep Look Into the Wild and Not-So-Wild World of Bumblebees
A Deep Look Into the Wild and Not-So-Wild World of Bumblebees Over the past several decades the lives of the domesticated and native pollinators have increasingly overlapped Jude Isabella, bioGraphic September 17, 2025 8:00 a.m. The domestication of some species of bumblebee has had unintended consequences. Grant Callegari / Hakai Institute Bumblebees are lovable, adorable and admirably occupied. They tumble along like toddlers drunk on the sweet smells of pretty flowers, breathing in one, then another and another. If Winnie-the-Pooh were an insect, he would be a bumblebee—a fuzzy, chubby, stinging insect that rarely stings. But I had no idea how much I cared about bumblebees until I had trouble meeting one particular species: the western bumblebee, Bombus occidentalis. Even before that, during the Covid-19 pandemic when my physical world contracted, a different apian wonder lured me into the big world of bumblebees. I had a garden, thankfully, and while working remotely, I had more time to consider its denizens. Cute and rotund, the bumblebees that routinely buzzed my tomato blossoms were small delights at a time when the world felt particularly grim. I snapped a photo of one, uploaded it to a website devoted to bumblebee identification and discovered it was a native species called Bombus vosnesenskii, the yellow-faced bumblebee. A sunny-blond mask covers its face and spreads across what I think of as its shoulders, like a fur wrap. Another strip of yellow near its tail contrasts with its otherwise black body. Enchanted, I dug deeper into online sources about bees, and B. vosnesenskii led me to B. occidentalis—also known as the white-bottomed or white-tailed bumblebee—the species that would have been pollinating my tomatoes in Victoria, British Columbia, some 30 years ago. Since then, B. occidentalis has slipped from being the most common bumblebee species in western North America to noticeably uncommon. In some areas, its populations are down 90 percent from what they were historically. The story of B. vosnesenskii has the opposite trajectory. In 1996, entomologists in British Columbia thought the bumblebee was in need of threatened or endangered status in the province. By 2000—not long after B. occidentalis populations crashed—researchers documented a dramatic B. vosnesenskii range expansion in the province, especially in the Lower Mainland and on Vancouver Island. Bombus vosnesenskii—the yellow-faced bumblebee—has expanded its range in British Columbia in the past couple of decades. Julia Hiebaum / Alamy Stock Photo Sure enough, everywhere I looked in my small pandemic bubble—in the garden, in urban parks, along the seashore—I saw B. vosnesenskii and other natives, but no B. occidentalis. I became fixated with the bee and its plight as an augur for an impoverished world. In a sense, my quest felt like an apology to the bee for my previous inattention. As I ventured deeper into B. occidentalis territory, I realized how dramatically the spheres of wild and lab-born bees have collided over the past few decades. The reality for B. occidentalis and many of its brethren is anything but cute. From a distance, Sarah Johnson’s hair looks like a floral bouquet. Standing still in a sea of beach grass infused with introduced Queen Anne’s lace, the bee biologist’s streaks of chartreuse, mauve, azure and garnet shine bright against the pearly blossoms bumblebees busily devour. We’re on a bumblebee safari in Bella Coola, a small town nestled along an inlet on the British Columbia coast. Johnson traveled here on a road trip with her dad in 2019. At the time, Johnson, who had become an incurable bee stalker while studying biology as an undergrad, was a graduate student at Simon Fraser University in Burnaby, British Columbia, researching how wildfire affects bumblebee communities. Beside Bella Coola’s ferry terminal, she spotted B. occidentalis on goldenrod. “Every single flower had a bumblebee,” she recalls, and not just any bee; it was B. occidentalis, which had become rare across much of its range in the province by then. “I was starting to freak out—‘Wow, this is amazing!’—so we drove around, and they were everywhere. There were tons of them. It was a time warp into the past,” Johnson recalls. “This is what their populations would have looked like.” Sarah Johnson, a bee biologist, looks for Bombus occidentalis—the western bumblebee—in an estuary in Bella Coola, British Columbia, where she first chanced upon a population in 2019. Grant Callegari / Hakai Institute I reached out to Johnson after grazing the internet looking for B. occidentalis sightings, and she offered to meet me here, five years after her last visit, hoping the site was still abuzz. On this June day in 2024, the temperature is 61 degrees Fahrenheit—a little chilly, but the fuzz that covers bumblebees acts like a jacket, so they’re often the first pollinators on the scene in spring and the last to exit in fall, when it’s too cold for many other pollen gatherers. The smell on the breeze is botanical, with a hint of licorice and the sweet sap of cottonwood trees lining the shoreline. “There’s an occidentalis!” Johnson says as she points to one clambering over a blossom among the ivory floral canopy. “Two more! And another.” She smiles and sighs. We watch the bumblebees forage. With the combs and brushes on the inside of their legs, they stuff pollen into bristly baskets on their hind legs. A bit of nectar mixed with saliva keeps the pollen moist and sticky so it stays put—all of the million or so golden grains in each basket. This site, a beach, does not fit the established understanding of ideal bumblebee habitat: It’s wet, and the flowers are sparse. But the known world of wild bumblebees is like a 2,000-year-old map: devoid of details and hopelessly myopic. B. occidentalis, it seems, like this location just fine. When Johnson, founding president of the Native Bee Society of British Columbia, stumbled upon this B. occidentalis hot spot, she was well aware that the species was on a downward spiral. She, like other bee biologists, suspected disease was to blame. So soon after she first spotted the bees in 2019, she gathered a handful of B. occidentalis, along with specimens of another native, Bombus vancouverensis—also called the Vancouver bumblebee—that were buzzing around Bella Coola, and she brought them back to her lab. Peering through a microscope, Johnson sliced into their abdomens and peeled back their insides to assess their disease load, something she would do when running a bumblebee recovery program for a nonprofit conservation organization in Ontario in the mid-2010s. Under the light of the microscope, B. occidentalis glowed with spores of Vairimorpha bombi—a fungus implicated in the great bumblebee die-off in the 1990s and originally known as Nosema bombi. A known pathogen of bees in general, the fungus seems particularly problematic for B. occidentalis, and researchers suspect that captive-bred bumblebees helped its spread to the wild. The B. vancouverensis she collected had no fungus. Since Johnson’s dissection was a one-off assessment, the scientific takeaway is fuzzy, though it feeds into the general consensus among some bee biologists that B. occidentalis appears more susceptible to agents of disease than most other bumblebee species. Why B. occidentalis in Bella Coola has managed to thrive despite the heavy fungal load is unclear, says Johnson. But it’s likely that the bees have fewer environmental stressors overall undermining their health here. B. occidentalis forages for pollen on Queen Anne’s lace in the Bella Coola estuary. Grant Callegari / Hakai Institute During our visit, Johnson wades through the waist-high flowers, climbing over driftwood and skirting discarded fishing detritus, her camera ready. “So cute,” she murmurs as a bumblebee skitters across an umbrella-shaped cluster of flowers. I feel like I’m on a bumblebee safari, and like all good safari guides, Johnson is happy to dole out facts about the wildlife, with tons of caveats—there are many species, and many of them are under-investigated. Most bumblebees nest underground, moving into abandoned rodent burrows or finding space at the bottom of fence posts or in the roots of trees, she tells me. Those that dwell aboveground tuck themselves behind house shingles, occupy birdhouses or nestle into other nooks they find. Each spring, hibernating queens emerge from their winter homes and disperse to establish their own nests. Eventually, female workers hatch from the queen’s first batch of eggs. The workers survive only a few weeks, toiling to deliver nectar and pollen back to the nest to benefit the next generation. Males, with shaggier, thinner legs, don’t collect pollen; they solely exist to perpetuate the hive, as if they are the ones in red in The Handmaid’s Tale. They mate with the queen late in the season. When the hive dies off, the queen’s end-of-season offspring, her potential successors, hibernate until it’s time to start their own colonies. Johnson shares these bumblebee basics through public outreach tables at farmer’s markets and other events. She also provides expert identification for the database Bumblebee Watch, where amateur enthusiasts can upload pictures of bees they’ve tracked. Public databases allow researchers to track the movements of and make educated guesses about bumblebee populations. Johnson points out that B. vosnesenskii—the yellow-faced bumblebee in my garden—may be continuing its range expansion, perhaps filling the B. occidentalis niche. Yet the story playing out beyond the sightings is a complicated one. It unspools in laboratories where scientists tinker with domesticated pollinators; in greenhouses where lab-born bees are released en masse; and in increasingly simplified agricultural landscapes that favor efficiency over diversity. Until B. occidentalis caught my imagination, I had no idea that bumblebees are akin to valuable livestock and that some species have already been domesticated on a large scale. The more familiar pollinators are non-native honeybees, probably first carried from Europe to North America in 1622 by English colonists of Virginia. Today, honeybees are integral to the food system in North America, though their services vary. In the United States, for example, they pollinate 100 percent of almonds but only about 25 percent of pumpkins. And they’re poor pollinators for one of the most lucrative crops: tomatoes. The tomato business is enormous. Globally, the market value of tomatoes is over $200 billion annually, compared with apples at around $100 billion. Bumblebees are ideal tomato pollinators because they are plump, they are hairy, and they vibrate. Tomatoes need that buzz: The high-frequency vibration of a bumblebee’s thoracic muscles shakes pollen from the plant’s flowers. “To anthropomorphize,” says Jon Koch, who was until recently a research entomologist at the U.S. Department of Agriculture in Utah, “that’s why we benefit, or the world does—because they’re not very good at wiping their mouths. A lot of pollen ends up on their own bodies.” Bumblebees then transfer the pollen grains between blossoms as they dance from plant to plant. Honeybees, by contrast, don’t vibrate, and they struggle to reach the pollen at the end of tomato blossoms. Being inside a greenhouse also tends to disorient honeybees, so they bang against the glass instead of working. Bombus mixtus is a commonly found bumblebee species native to western North America, in the Rocky Mountains to the coast, from Alaska south to northern California. Grant Callegari / Hakai Institute Before they could buy commercial bumblebees in the 1980s, tomato greenhouse growers hand-pollinated with electric vibrating wands. Compared with this laborious task, bumblebee pollination can lead to plumper fruit and a 30 percent increase in tomato yield. In addition to their effect on greenhouse tomatoes, domesticated bumblebees have increased the yields of bell peppers, cucumbers, eggplants and, in some regions, field crops like blueberries, strawberries and cranberries. Worldwide, 5 species of bumblebees out of about 265 are commercial crop pollinators. B. occidentalis was briefly one of them. Bumblebee domestication started more than a century ago, when farmers began moving four bumblebee species, including a species called Bombus terrestris, the buff-tailed bumblebee, from the United Kingdom to New Zealand—once a bumblebee-free land—to pollinate feed crops such as alfalfa and red clover. The effort to raise bumblebees in captivity progressed in fits and starts for much of the 20th century. But the commercial value of B. terrestris soared soon after a Belgian veterinarian and bumblebee breeder named Roland de Jonghe released a colony into a tomato grower’s greenhouse in the Netherlands in 1985. The grower saw his yield increase, and he noticed that his bumblebee-kissed greenhouse tomatoes were also prettier—with rounded flesh and fewer blemishes—than the hand-pollinated fruit of his competitors. He made a record profit. Within a few years, tomato growers in the Netherlands, Belgium and Luxembourg all began using B. terrestris for pollination, and de Jonghe launched Biobest, which is now one of the world’s largest suppliers of domesticated B. terrestris and other commercial pollinator species. All along, bumblebee breeders understood that their wards were prone to jailbreaking. As Koch points out, “Bumblebees are great escape artists. I’ve learned that they will find the smallest hole anywhere, and they’re persistent.” For that reason, breeders raising bumblebees for the greenhouse industry endeavored to use species local to where they’d be employed. It didn’t always work. In Australia, for example, breeders tried native great carpenter bees, but they were uncooperative in confined settings. In North America, breeders set their sights on domesticating two bumblebees native to Canada and the U.S.: B. impatiens, the most common bumblebee in the east, and B. occidentalis, the most common bumblebee in the west. The quest to create a pollinator from wild B. impatiens worked; B. occidentalis, however, faltered. In the late 1990s, not long into industrial-scale breeding of B. occidentalis, the V. bombi fungus felled commercial populations. Wild B. occidentalis soon fell ill as well, possibly infected by some of the domesticated variety released into greenhouses and farm fields. If hysteria ensued—as it did when colony collapse disorder first struck honeybees in 2006—it seemed to be kept within the sphere of breeders, researchers, trade publications and maybe local farm news. Commercial breeders abandoned B. occidentalis by 1999. “The hothouse tomato industry faced a calamity in terms of productivity,” says Paul van Westendorp, the chief apiarist for the province of British Columbia before his recent retirement. Meanwhile, growers on the other side of the continent, in places like Ontario and New York, were relying on B. impatiens, a proven winner in domestication. Western growers clamored for permission from their governments to import B. impatiens. Promises were made to keep the non-native bees inside, and permission was granted. “We always knew that 100 percent control was perhaps idealistic or unrealistic, but it was considered to be perhaps not a great threat as such,” van Westendorp says. Washington and California also gave permission, with conditions, while Oregon was a holdout. In greenhouses, bumblebee colonies live in a cardboard box about the size of a banker’s box. Inside is a plastic chamber for the hive and where the queen lays her eggs. A round opening, an excluder, to the outside allows smaller workers out, but it should be too small for queens. Did B. impatiens escape greenhouses in western North America? If you ask Gary Jones, program manager for the B.C. Greenhouse Grower’s Association, the evidence is circumstantial. “It’s an assumption,” he says. The assumption is based on surveys by researchers in the spring of 2003 and 2004 of blueberry and strawberry fields in the Lower Mainland, where hundreds of greenhouses dot agricultural fields: They found over 500 B. impatiens, including a queen, at two different sites, roughly one and three miles from greenhouses, typical foraging distances for bumblebees. Commercially produced bumblebees arrive at greenhouses in cardboard boxes that serve as their hives. Carlos Gonzalez / Minneapolis Star Tribune / Alamy Stock Photo Aside from using excluders, growers are also supposed to euthanize hives that have finished their pollinating job, usually by freezing them. Yet there are no rules specifying how long to freeze the hives to kill the bees before disposing of them, says Sheila Colla*, a conservation scientist at York University in Toronto, who led the bee surveys in British Columbia’s blueberry and strawberry fields. And no regulatory agency has anyone methodically inspecting domesticated bumblebees in the province’s commercial greenhouses. Washington and California have no monitoring processes in place either. “I wonder if they’re just being dumped into dumpsters, and that’s how they’re getting out,” says Colla. Katie Buckley with the Washington State Department of Agriculture also knows that some greenhouse growers sold hives to other farmers, who may have placed them outside. That was “not uncommon practice,” she says, referring to the early days of B. impatiens in the West. “There were chains of people that these hives would go through.” No governmental entity checked for escapees. Hunt for bumblebees in farm fields in the Lower Mainland today, and 40 percent will be B. impatiens, as revealed by scientists from the University of British Columbia in 2024, helping fill the void left by B. occidentalis, once the humming majority. While B. impatiens is not responsible for B. occidentalis’ worrisome decline, it may have kept the threatened bee from rebounding in certain areas, through competition or by spreading disease. And even though colonies of native bumblebees—domesticated B. vosnesenskii and another hometown buzz called Bombus huntii—are finally available, it seems unlikely we’ll ever put a lid back on feral B. impatiens. They’ve become a permanent component of the region’s pollinator mix. The question is: What will this now-common species do to wild bee diversity in the long term? By 2017, Washington State firmly jumped on the feral bumblebee worry train when a single image of B. impatiens uploaded to an online insect identification site caught the eye of Chris Looney, who studies insects at the Washington State Department of Agriculture. Looney is famous—at least in some circles—for his work on tracking and eradicating the Asian giant hornet (aka murder hornet, Vespa mandarinia). The photo was taken in Blaine, Washington, roughly half a mile from the Canadian border. “This is only the third location, I would say on Earth, where a bumblebee has been introduced in a place where other bumblebees live,” Looney says over a video chat from his office in Olympia, Washington. Aside from the northwest coast of North America, the other two places are Japan and Chile. In Japan, B. terrestris imported from Europe may be interfering with the mating of native species and competing for nests, but the effects have been subtle so far. In Chile, the effects are profound. Introduced B. terrestris have spread south into Argentina, and now they’re displacing the native ginger-furred Bombus dahlbomii throughout Patagonia, a revelation made in 2013 by Carolina Morales, at Argentina’s National University of Comahue, and her colleagues. B. dahlbomii, the largest bumblebee on Earth—likened to a flying mouse—is the region’s only native bumblebee. Bombus dahlbomii, Patagonia’s only native bumblebee, has struggled since Chile introduced Bombus terrestris into greenhouses in 1997. The largest bumblebee in the world, B. dahlbomii is now considered endangered. bbr0wn / iNaturalist “In that case, the impacts [in Patagonia] were immediate and obvious,” Looney says. In the Pacific Northwest, the trajectory is less clear. “Will [B. impatiens] just slot in and not really be a competitor? Or will they have disparate impacts on some native bee species but not others? Who knows, right?” Looney and a colleague visited Blaine and immediately found B. impatiens. He then investigated the potential for B. impatiens to spread even further through a modeling study using climate data and habitat needs: The bee has the potential to go big and colonize the coast from British Columbia’s Haida Gwaii archipelago to California’s San Francisco Bay. In 2022, Looney launched a four-year survey. With colleagues, including Koch, who was then at the U.S. Department of Agriculture, he put 46 sites under surveillance for B. impatiens in Washington and in British Columbia’s Lower Mainland. One question the team hopes to answer is whether the bees have a preference for certain landscapes, and if so, which ones. Anecdotally, they’re associated with urban and suburban gardens, parks and agricultural fields, but Looney’s team has also found them on mountains and forested foothills. “Obviously, they found something to eat up there,” he says. He’s also found that the traps he set for the Asian giant hornet, baited with a mimosa-like concoction—rice wine and orange juice—tend to lure B. impatiens. Chris Looney, an entomologist at the Washington State Department of Agriculture, holds a bottle trap used to capture invasive Asian giant hornets. Bombus impatiens are also drawn to the traps. Paul Christian Gordon / Alamy Stock Photo In October 2022, Looney found 30 of the introduced bumblebees—way more than the usual handful he encounters—inside a hornet trap set in a meadow in Lynden, Washington. Lots of males and queens were flying around, a signal that it was the end of a colony cycle. Another pass at the site in spring 2024 turned up nine B. impatiens nests under the ground. “Big nests,” Looney says—far bigger than those produced by B. occidentalis, which typically contain a few hundred bees. In the fall, he and his team used pickaxes, shovels and a shop vac to collect a colony and bring it back for dissection. Based on the number of larval cells they found—3,600—they estimate that collectively, the nine nests in that meadow habitat could have produced 3,933 gynes, potential queens. About 60 percent survive overwintering, which means that the nests could produce 2,360 would-be queens in spring. The team is far from generating an overall hypothesis about whether the flying infringers are worrisome adversaries or tolerable neighbors for native species. Looney, Koch, Colla and others have noticed that the bee from the east shows up to pollinate later in the season than most natives. The queens are out at the same time as other species’ queens, but the workers take their sweet time heading out to flowering fields—perhaps because they’re reliant on introduced plants, cultivars bred to provide a cascading series of blooms all summer long, or fruits and vegetables ready to harvest at various times over a growing season. From surveys of the Lower Mainland, bee biologists at the University of British Columbia found that B. impatiens binge on the pollen of cultivated dahlias, tomatoes, blueberries and other plants found in suburban gardens. The bee dominates parks in the Vancouver metro area, too. Despite the apparent size of the feral population, the British Columbia government continues to sit on its hands. B. impatiens is no longer welcome in Washington’s greenhouses, though the domesticated eastern worker continues to labor in California. Counties in California inspect greenhouses before issuing permits, yet that state also has a documented feral population. Oregon continues to forbid B. impatiens and so far has no established populations. Bee biologist Lincoln Best at Oregon State University has had teams searching for them since 2018 when he launched the Oregon Bee Atlas. He believes they are dispersing along the coast and into watersheds, finding open areas with decent bumblebee habitat, and that their expansion from either Washington or California into Oregon is probable. “It’s just a matter of time,” he says. On another bumblebee safari, to the Lower Mainland, the apparent gateway of B. impatiens to the West, I meet Sandra Gillespie, a bee biologist with the University of the Fraser Valley in Abbotsford, British Columbia. Gillespie’s focus is on pathogens and bumblebees, but Looney and Koch asked her to join their survey of B. impatiens. Abbotsford is part farm community, part suburbia. To meet Gillespie, I drive down a two-lane road lined with greenhouses and commercial blueberry crops and crowded with trucks, cars, and the odd tractor. “Oh, here’s an impatiens—she’s moving fast,” Gillespie says as we stand at a blackberry patch in a public park. I blink, and the bee is gone. We’re about a mile from the nearest greenhouse, which means the B. impatiens is either feral or a recent escapee. “Once they built that greenhouse, that’s when I started seeing Bombus impatiens at one of my field sites, over there,” she says, pointing north toward the Fraser River. She’s been monitoring the same sites for eight years and rarely sees a B. occidentalis, although she’s spotted them on Vancouver Island. Sandra Gillespie, a bee biologist at the University of the Fraser Valley in British Columbia, studies pathogens in bumblebees. Toby Hall / Hakai Institute A couple of other native bumblebee species whizz by before we stroll to a patch of native fireweed where bumblebees gulp an abundance of nectar from the bubblegum pink petals. Different plants offer different nutritional value, and research has shown that bumblebees thrive on a varied diet. But the intense commercialization of the blueberry crop in Abbotsford has simplified the landscape with thousands of shrubs. “Blueberries are attractive to bumblebees because there are so many of them,” says Gillespie, noting they don’t offer bees much protein. She equates the vast blueberry fields to big box stores, teeming with processed foods. It’s hot, and the bees are fast. Gillespie points to a couple of B. impatiens flying deep into the flower patch. Then she chuckles: A bumblebee in front of us sticks its face deep into a bright pink blossom. It’s a B. vosnesenskii, the yellow-faced bumblebee that first lured me into the world of bees. Earlier in the season, Gillespie collected a handful of B. vosnesenskii queens from the wild and placed them in a box designed for brood rearing, as a means of learning more about the behaviors of her study subjects. Koch and Looney did the same in a couple of different sites in Washington. Gillespie has had little success so far. “I think there’s something wrong with our queens,” she says, clearly frustrated, noting it could also be the lab setup. For publicly funded researchers and commercial breeders alike, figuring out how to rear bees in labs has been notoriously finnicky since the beginning. Gillespie trains students to identify and net bee pollinators in her survey sites. Toby Hall / Hakai Institute Koppert, a commercial breeding operation based in the Netherlands, began raising B. vosnesenskii around 2007, and early results were mixed—the bee was not easy to domesticate. But eventually the company got it right, and commercial sales began in 2020. What did it get right? Who knows. Production methods are proprietary. “As you can imagine, we compete heavily with the likes of Biobest and other smaller local producers all across the world,” says Martin Wohlfarter, Koppert’s global regulatory affairs specialist. Fair enough: The pollination-services industry was worth $2.5 billion in 2024. B. vosnesenskii could prove as lucrative as B. impatiens—it’s one of the two domesticated bumblebees allowed to pollinate crops in Washington and Oregon, both in fields and greenhouses. If British Columbia ever bans B. impatiens, it is likely that B. vosnesenskii and B. huntii will take their place. But will using domesticated native bumblebees ultimately prove better than using non-native equivalents? Well, domesticated B. vosnesenskii can potentially overwhelm habitat and outcompete other species, but more than one researcher points out that they’ll mostly stick with the “big box” floral department they’re released into. More worrisome is the spread of disease to wild bumblebees if an outbreak of a fungus, virus, parasite or bacteria hits a lab or two. What is known is that since the start of the commercial bumblebee breeding industry, infections caused by V. bombi, the fungus that sliced into B. occidentalis populations, have risen in wild species in western North America. Maybe bumblebees meet at a flower patch, alight on some of the same blossoms, each make their own little messes while sipping nectar and gathering pollen, and a pathogen hitches a ride back to a wild hive. Felix Wäckers, head of research and development at Biobest, based in Belgium, is an ecologist and former academic. He joined Biobest 16 years ago, and at the time, he says, shipping pollinators around the globe was not acknowledged—at least by the industry—as a risk to native bumblebee species. Since then, he says, disease protocols have become more rigorous. For instance, scientists will breed queens for multiple generations to weed out potential pathogens from the original wild progenitors. Biobest has also bred native Japanese and South American bumblebees and has stopped selling B. terrestris to Japan and Chile. “I think as an industry, we have taken considerable steps over the last one and a half decades to minimize the impact,” Wäckers says. “That doesn’t mean that what happened with Chile is not a problem.” It also doesn’t mean other companies have stopped selling the non-native bees to Chile or Japan. Colla, the conservation scientist, and her colleagues are calling for a “bumblebee clean stock certification program” across North America to reduce disease risk in captive production, which in turn would reduce the risk of infections in wild pollinators and other insects. As Colla points out, pathogen spillover is a regular occurrence between livestock and their wild counterparts—between cattle and bison; between farmed salmon and wild salmon; between poultry and wild birds. My final bumblebee safari never pans out. I’m home, sick with a case of dramatic irony, infected with the Covid-19 virus. Looney, Koch and their team head out without me to Whatcom County in Washington to check their B. vosnesenskii colonies. They’re doing well. Koch’s lab manager Tien Lindsay sends me photos. The mid-September day looks ablaze in foliage as the team checks a hive surrounded by the white and red blossoms of rugosa, a lovely flowering shrub from eastern Asia. Against an emerald backdrop of western red cedar striped with the white bark of an aspen, a scientist peers inside a white box. The yellow-faced livestock are hidden from the camera. Unlike conventional livestock, bumblebees play a role in the agricultural system that is mostly hidden from consumers. It’s not intentional, just business: Bumblebees have become invisible in a system where profit comes first, food second and biodiversity barely registers. A handful of bumblebee species are tools, necessary tools for growers big and small, including the family-run greenhouse a couple miles from my house that sells the most exquisite heirloom tomatoes at the summer farmers market. The corporate point of view isn’t wrong. An economy that hinges on one metric—money—rewards profit-driven behavior. But money is like a god that demands complete allegiance, leaving less space for the gods of small things, for the 260 or so other wild bumblebees that do not fit into today’s economic system but are likely impacted by it. This is not the end of the story. Farmers have always been creative problem solvers. Change the goal, and farmers and researchers—highly skilled people—can transform the agricultural landscape into healthier ecosystems with space for all bee species. In fact, domesticating bumblebees led to a boost in biocontrol research, resulting in new ways to manage pests without relying solely on chemicals to massacre other life forms. Maybe change begins with an idea: to look at the world through the eyes of wild pollinators while acknowledging them as partners in our food systems. If we simultaneously reject the simplification of agricultural landscapes, we can create diverse food-producing ecosystems that encourage a variety of species that interact for the benefit of the whole. B. vosnesenskii, a bumblebee native to western North America, rests on Looney’s hand at one of his survey sites in Washington State. Chris Looney Another picture in the batch that Lindsay sends me has a caption: “A Bombus vosnesenskii worker bee rests on Dr. Chris Looney’s finger. We were expressing our gratitude for her efforts and services.” Maybe change starts with that. Travel and photography support for this story came from the Tula Foundation. * Sheila Colla passed away on July 6, 2025. As a journalist, I only knew Sheila through a video interview and emails. She answered questions with clarity, patience and kindness and was always responsive. When we chatted many months ago, she was outside with her students, giving thoughtful answers to my questions, occasionally engaging with someone in the background, smiling all the while. She seemed unflappable. When I interviewed other biologists for this story, they often referred to Sheila’s work. From our brief encounter, Sheila came across as a matriarch of the bee biology world, a powerful, influential woman and scientist who cared deeply about the natural world. Please read about her remarkable sojourn on this corporeal plane here. This story originally appeared in bioGraphic, an independent magazine about nature and regeneration powered by the California Academy of Sciences. Get the latest Science stories in your inbox.
Over the past several decades the lives of the domesticated and native pollinators have increasingly overlapped
A Deep Look Into the Wild and Not-So-Wild World of Bumblebees
Over the past several decades the lives of the domesticated and native pollinators have increasingly overlapped
Jude Isabella, bioGraphic

Bumblebees are lovable, adorable and admirably occupied. They tumble along like toddlers drunk on the sweet smells of pretty flowers, breathing in one, then another and another. If Winnie-the-Pooh were an insect, he would be a bumblebee—a fuzzy, chubby, stinging insect that rarely stings. But I had no idea how much I cared about bumblebees until I had trouble meeting one particular species: the western bumblebee, Bombus occidentalis.
Even before that, during the Covid-19 pandemic when my physical world contracted, a different apian wonder lured me into the big world of bumblebees. I had a garden, thankfully, and while working remotely, I had more time to consider its denizens. Cute and rotund, the bumblebees that routinely buzzed my tomato blossoms were small delights at a time when the world felt particularly grim. I snapped a photo of one, uploaded it to a website devoted to bumblebee identification and discovered it was a native species called Bombus vosnesenskii, the yellow-faced bumblebee. A sunny-blond mask covers its face and spreads across what I think of as its shoulders, like a fur wrap. Another strip of yellow near its tail contrasts with its otherwise black body.
Enchanted, I dug deeper into online sources about bees, and B. vosnesenskii led me to B. occidentalis—also known as the white-bottomed or white-tailed bumblebee—the species that would have been pollinating my tomatoes in Victoria, British Columbia, some 30 years ago. Since then, B. occidentalis has slipped from being the most common bumblebee species in western North America to noticeably uncommon. In some areas, its populations are down 90 percent from what they were historically.
The story of B. vosnesenskii has the opposite trajectory. In 1996, entomologists in British Columbia thought the bumblebee was in need of threatened or endangered status in the province. By 2000—not long after B. occidentalis populations crashed—researchers documented a dramatic B. vosnesenskii range expansion in the province, especially in the Lower Mainland and on Vancouver Island.

Sure enough, everywhere I looked in my small pandemic bubble—in the garden, in urban parks, along the seashore—I saw B. vosnesenskii and other natives, but no B. occidentalis. I became fixated with the bee and its plight as an augur for an impoverished world. In a sense, my quest felt like an apology to the bee for my previous inattention. As I ventured deeper into B. occidentalis territory, I realized how dramatically the spheres of wild and lab-born bees have collided over the past few decades. The reality for B. occidentalis and many of its brethren is anything but cute.
From a distance, Sarah Johnson’s hair looks like a floral bouquet. Standing still in a sea of beach grass infused with introduced Queen Anne’s lace, the bee biologist’s streaks of chartreuse, mauve, azure and garnet shine bright against the pearly blossoms bumblebees busily devour.
We’re on a bumblebee safari in Bella Coola, a small town nestled along an inlet on the British Columbia coast. Johnson traveled here on a road trip with her dad in 2019. At the time, Johnson, who had become an incurable bee stalker while studying biology as an undergrad, was a graduate student at Simon Fraser University in Burnaby, British Columbia, researching how wildfire affects bumblebee communities. Beside Bella Coola’s ferry terminal, she spotted B. occidentalis on goldenrod. “Every single flower had a bumblebee,” she recalls, and not just any bee; it was B. occidentalis, which had become rare across much of its range in the province by then.
“I was starting to freak out—‘Wow, this is amazing!’—so we drove around, and they were everywhere. There were tons of them. It was a time warp into the past,” Johnson recalls. “This is what their populations would have looked like.”

I reached out to Johnson after grazing the internet looking for B. occidentalis sightings, and she offered to meet me here, five years after her last visit, hoping the site was still abuzz. On this June day in 2024, the temperature is 61 degrees Fahrenheit—a little chilly, but the fuzz that covers bumblebees acts like a jacket, so they’re often the first pollinators on the scene in spring and the last to exit in fall, when it’s too cold for many other pollen gatherers. The smell on the breeze is botanical, with a hint of licorice and the sweet sap of cottonwood trees lining the shoreline. “There’s an occidentalis!” Johnson says as she points to one clambering over a blossom among the ivory floral canopy. “Two more! And another.” She smiles and sighs.
We watch the bumblebees forage. With the combs and brushes on the inside of their legs, they stuff pollen into bristly baskets on their hind legs. A bit of nectar mixed with saliva keeps the pollen moist and sticky so it stays put—all of the million or so golden grains in each basket. This site, a beach, does not fit the established understanding of ideal bumblebee habitat: It’s wet, and the flowers are sparse. But the known world of wild bumblebees is like a 2,000-year-old map: devoid of details and hopelessly myopic. B. occidentalis, it seems, like this location just fine.
When Johnson, founding president of the Native Bee Society of British Columbia, stumbled upon this B. occidentalis hot spot, she was well aware that the species was on a downward spiral. She, like other bee biologists, suspected disease was to blame. So soon after she first spotted the bees in 2019, she gathered a handful of B. occidentalis, along with specimens of another native, Bombus vancouverensis—also called the Vancouver bumblebee—that were buzzing around Bella Coola, and she brought them back to her lab.
Peering through a microscope, Johnson sliced into their abdomens and peeled back their insides to assess their disease load, something she would do when running a bumblebee recovery program for a nonprofit conservation organization in Ontario in the mid-2010s. Under the light of the microscope, B. occidentalis glowed with spores of Vairimorpha bombi—a fungus implicated in the great bumblebee die-off in the 1990s and originally known as Nosema bombi. A known pathogen of bees in general, the fungus seems particularly problematic for B. occidentalis, and researchers suspect that captive-bred bumblebees helped its spread to the wild. The B. vancouverensis she collected had no fungus. Since Johnson’s dissection was a one-off assessment, the scientific takeaway is fuzzy, though it feeds into the general consensus among some bee biologists that B. occidentalis appears more susceptible to agents of disease than most other bumblebee species. Why B. occidentalis in Bella Coola has managed to thrive despite the heavy fungal load is unclear, says Johnson. But it’s likely that the bees have fewer environmental stressors overall undermining their health here.

During our visit, Johnson wades through the waist-high flowers, climbing over driftwood and skirting discarded fishing detritus, her camera ready. “So cute,” she murmurs as a bumblebee skitters across an umbrella-shaped cluster of flowers. I feel like I’m on a bumblebee safari, and like all good safari guides, Johnson is happy to dole out facts about the wildlife, with tons of caveats—there are many species, and many of them are under-investigated.
Most bumblebees nest underground, moving into abandoned rodent burrows or finding space at the bottom of fence posts or in the roots of trees, she tells me. Those that dwell aboveground tuck themselves behind house shingles, occupy birdhouses or nestle into other nooks they find. Each spring, hibernating queens emerge from their winter homes and disperse to establish their own nests. Eventually, female workers hatch from the queen’s first batch of eggs. The workers survive only a few weeks, toiling to deliver nectar and pollen back to the nest to benefit the next generation. Males, with shaggier, thinner legs, don’t collect pollen; they solely exist to perpetuate the hive, as if they are the ones in red in The Handmaid’s Tale. They mate with the queen late in the season. When the hive dies off, the queen’s end-of-season offspring, her potential successors, hibernate until it’s time to start their own colonies.
Johnson shares these bumblebee basics through public outreach tables at farmer’s markets and other events. She also provides expert identification for the database Bumblebee Watch, where amateur enthusiasts can upload pictures of bees they’ve tracked. Public databases allow researchers to track the movements of and make educated guesses about bumblebee populations. Johnson points out that B. vosnesenskii—the yellow-faced bumblebee in my garden—may be continuing its range expansion, perhaps filling the B. occidentalis niche.
Yet the story playing out beyond the sightings is a complicated one. It unspools in laboratories where scientists tinker with domesticated pollinators; in greenhouses where lab-born bees are released en masse; and in increasingly simplified agricultural landscapes that favor efficiency over diversity.
Until B. occidentalis caught my imagination, I had no idea that bumblebees are akin to valuable livestock and that some species have already been domesticated on a large scale. The more familiar pollinators are non-native honeybees, probably first carried from Europe to North America in 1622 by English colonists of Virginia. Today, honeybees are integral to the food system in North America, though their services vary. In the United States, for example, they pollinate 100 percent of almonds but only about 25 percent of pumpkins. And they’re poor pollinators for one of the most lucrative crops: tomatoes.
The tomato business is enormous. Globally, the market value of tomatoes is over $200 billion annually, compared with apples at around $100 billion. Bumblebees are ideal tomato pollinators because they are plump, they are hairy, and they vibrate. Tomatoes need that buzz: The high-frequency vibration of a bumblebee’s thoracic muscles shakes pollen from the plant’s flowers. “To anthropomorphize,” says Jon Koch, who was until recently a research entomologist at the U.S. Department of Agriculture in Utah, “that’s why we benefit, or the world does—because they’re not very good at wiping their mouths. A lot of pollen ends up on their own bodies.” Bumblebees then transfer the pollen grains between blossoms as they dance from plant to plant. Honeybees, by contrast, don’t vibrate, and they struggle to reach the pollen at the end of tomato blossoms. Being inside a greenhouse also tends to disorient honeybees, so they bang against the glass instead of working.

Before they could buy commercial bumblebees in the 1980s, tomato greenhouse growers hand-pollinated with electric vibrating wands. Compared with this laborious task, bumblebee pollination can lead to plumper fruit and a 30 percent increase in tomato yield.
In addition to their effect on greenhouse tomatoes, domesticated bumblebees have increased the yields of bell peppers, cucumbers, eggplants and, in some regions, field crops like blueberries, strawberries and cranberries. Worldwide, 5 species of bumblebees out of about 265 are commercial crop pollinators. B. occidentalis was briefly one of them.
Bumblebee domestication started more than a century ago, when farmers began moving four bumblebee species, including a species called Bombus terrestris, the buff-tailed bumblebee, from the United Kingdom to New Zealand—once a bumblebee-free land—to pollinate feed crops such as alfalfa and red clover. The effort to raise bumblebees in captivity progressed in fits and starts for much of the 20th century. But the commercial value of B. terrestris soared soon after a Belgian veterinarian and bumblebee breeder named Roland de Jonghe released a colony into a tomato grower’s greenhouse in the Netherlands in 1985.
The grower saw his yield increase, and he noticed that his bumblebee-kissed greenhouse tomatoes were also prettier—with rounded flesh and fewer blemishes—than the hand-pollinated fruit of his competitors. He made a record profit. Within a few years, tomato growers in the Netherlands, Belgium and Luxembourg all began using B. terrestris for pollination, and de Jonghe launched Biobest, which is now one of the world’s largest suppliers of domesticated B. terrestris and other commercial pollinator species.
All along, bumblebee breeders understood that their wards were prone to jailbreaking. As Koch points out, “Bumblebees are great escape artists. I’ve learned that they will find the smallest hole anywhere, and they’re persistent.” For that reason, breeders raising bumblebees for the greenhouse industry endeavored to use species local to where they’d be employed. It didn’t always work. In Australia, for example, breeders tried native great carpenter bees, but they were uncooperative in confined settings. In North America, breeders set their sights on domesticating two bumblebees native to Canada and the U.S.: B. impatiens, the most common bumblebee in the east, and B. occidentalis, the most common bumblebee in the west. The quest to create a pollinator from wild B. impatiens worked; B. occidentalis, however, faltered.
In the late 1990s, not long into industrial-scale breeding of B. occidentalis, the V. bombi fungus felled commercial populations. Wild B. occidentalis soon fell ill as well, possibly infected by some of the domesticated variety released into greenhouses and farm fields. If hysteria ensued—as it did when colony collapse disorder first struck honeybees in 2006—it seemed to be kept within the sphere of breeders, researchers, trade publications and maybe local farm news.
Commercial breeders abandoned B. occidentalis by 1999. “The hothouse tomato industry faced a calamity in terms of productivity,” says Paul van Westendorp, the chief apiarist for the province of British Columbia before his recent retirement. Meanwhile, growers on the other side of the continent, in places like Ontario and New York, were relying on B. impatiens, a proven winner in domestication. Western growers clamored for permission from their governments to import B. impatiens. Promises were made to keep the non-native bees inside, and permission was granted. “We always knew that 100 percent control was perhaps idealistic or unrealistic, but it was considered to be perhaps not a great threat as such,” van Westendorp says. Washington and California also gave permission, with conditions, while Oregon was a holdout.
In greenhouses, bumblebee colonies live in a cardboard box about the size of a banker’s box. Inside is a plastic chamber for the hive and where the queen lays her eggs. A round opening, an excluder, to the outside allows smaller workers out, but it should be too small for queens. Did B. impatiens escape greenhouses in western North America? If you ask Gary Jones, program manager for the B.C. Greenhouse Grower’s Association, the evidence is circumstantial. “It’s an assumption,” he says. The assumption is based on surveys by researchers in the spring of 2003 and 2004 of blueberry and strawberry fields in the Lower Mainland, where hundreds of greenhouses dot agricultural fields: They found over 500 B. impatiens, including a queen, at two different sites, roughly one and three miles from greenhouses, typical foraging distances for bumblebees.

Aside from using excluders, growers are also supposed to euthanize hives that have finished their pollinating job, usually by freezing them. Yet there are no rules specifying how long to freeze the hives to kill the bees before disposing of them, says Sheila Colla*, a conservation scientist at York University in Toronto, who led the bee surveys in British Columbia’s blueberry and strawberry fields. And no regulatory agency has anyone methodically inspecting domesticated bumblebees in the province’s commercial greenhouses. Washington and California have no monitoring processes in place either. “I wonder if they’re just being dumped into dumpsters, and that’s how they’re getting out,” says Colla.
Katie Buckley with the Washington State Department of Agriculture also knows that some greenhouse growers sold hives to other farmers, who may have placed them outside. That was “not uncommon practice,” she says, referring to the early days of B. impatiens in the West. “There were chains of people that these hives would go through.” No governmental entity checked for escapees.
Hunt for bumblebees in farm fields in the Lower Mainland today, and 40 percent will be B. impatiens, as revealed by scientists from the University of British Columbia in 2024, helping fill the void left by B. occidentalis, once the humming majority. While B. impatiens is not responsible for B. occidentalis’ worrisome decline, it may have kept the threatened bee from rebounding in certain areas, through competition or by spreading disease. And even though colonies of native bumblebees—domesticated B. vosnesenskii and another hometown buzz called Bombus huntii—are finally available, it seems unlikely we’ll ever put a lid back on feral B. impatiens. They’ve become a permanent component of the region’s pollinator mix. The question is: What will this now-common species do to wild bee diversity in the long term?
By 2017, Washington State firmly jumped on the feral bumblebee worry train when a single image of B. impatiens uploaded to an online insect identification site caught the eye of Chris Looney, who studies insects at the Washington State Department of Agriculture. Looney is famous—at least in some circles—for his work on tracking and eradicating the Asian giant hornet (aka murder hornet, Vespa mandarinia). The photo was taken in Blaine, Washington, roughly half a mile from the Canadian border.
“This is only the third location, I would say on Earth, where a bumblebee has been introduced in a place where other bumblebees live,” Looney says over a video chat from his office in Olympia, Washington. Aside from the northwest coast of North America, the other two places are Japan and Chile. In Japan, B. terrestris imported from Europe may be interfering with the mating of native species and competing for nests, but the effects have been subtle so far. In Chile, the effects are profound. Introduced B. terrestris have spread south into Argentina, and now they’re displacing the native ginger-furred Bombus dahlbomii throughout Patagonia, a revelation made in 2013 by Carolina Morales, at Argentina’s National University of Comahue, and her colleagues. B. dahlbomii, the largest bumblebee on Earth—likened to a flying mouse—is the region’s only native bumblebee.

“In that case, the impacts [in Patagonia] were immediate and obvious,” Looney says. In the Pacific Northwest, the trajectory is less clear. “Will [B. impatiens] just slot in and not really be a competitor? Or will they have disparate impacts on some native bee species but not others? Who knows, right?”
Looney and a colleague visited Blaine and immediately found B. impatiens. He then investigated the potential for B. impatiens to spread even further through a modeling study using climate data and habitat needs: The bee has the potential to go big and colonize the coast from British Columbia’s Haida Gwaii archipelago to California’s San Francisco Bay.
In 2022, Looney launched a four-year survey. With colleagues, including Koch, who was then at the U.S. Department of Agriculture, he put 46 sites under surveillance for B. impatiens in Washington and in British Columbia’s Lower Mainland. One question the team hopes to answer is whether the bees have a preference for certain landscapes, and if so, which ones. Anecdotally, they’re associated with urban and suburban gardens, parks and agricultural fields, but Looney’s team has also found them on mountains and forested foothills. “Obviously, they found something to eat up there,” he says. He’s also found that the traps he set for the Asian giant hornet, baited with a mimosa-like concoction—rice wine and orange juice—tend to lure B. impatiens.

In October 2022, Looney found 30 of the introduced bumblebees—way more than the usual handful he encounters—inside a hornet trap set in a meadow in Lynden, Washington. Lots of males and queens were flying around, a signal that it was the end of a colony cycle. Another pass at the site in spring 2024 turned up nine B. impatiens nests under the ground. “Big nests,” Looney says—far bigger than those produced by B. occidentalis, which typically contain a few hundred bees. In the fall, he and his team used pickaxes, shovels and a shop vac to collect a colony and bring it back for dissection. Based on the number of larval cells they found—3,600—they estimate that collectively, the nine nests in that meadow habitat could have produced 3,933 gynes, potential queens. About 60 percent survive overwintering, which means that the nests could produce 2,360 would-be queens in spring.
The team is far from generating an overall hypothesis about whether the flying infringers are worrisome adversaries or tolerable neighbors for native species. Looney, Koch, Colla and others have noticed that the bee from the east shows up to pollinate later in the season than most natives. The queens are out at the same time as other species’ queens, but the workers take their sweet time heading out to flowering fields—perhaps because they’re reliant on introduced plants, cultivars bred to provide a cascading series of blooms all summer long, or fruits and vegetables ready to harvest at various times over a growing season.
From surveys of the Lower Mainland, bee biologists at the University of British Columbia found that B. impatiens binge on the pollen of cultivated dahlias, tomatoes, blueberries and other plants found in suburban gardens. The bee dominates parks in the Vancouver metro area, too.
Despite the apparent size of the feral population, the British Columbia government continues to sit on its hands. B. impatiens is no longer welcome in Washington’s greenhouses, though the domesticated eastern worker continues to labor in California. Counties in California inspect greenhouses before issuing permits, yet that state also has a documented feral population. Oregon continues to forbid B. impatiens and so far has no established populations. Bee biologist Lincoln Best at Oregon State University has had teams searching for them since 2018 when he launched the Oregon Bee Atlas. He believes they are dispersing along the coast and into watersheds, finding open areas with decent bumblebee habitat, and that their expansion from either Washington or California into Oregon is probable. “It’s just a matter of time,” he says.
On another bumblebee safari, to the Lower Mainland, the apparent gateway of B. impatiens to the West, I meet Sandra Gillespie, a bee biologist with the University of the Fraser Valley in Abbotsford, British Columbia. Gillespie’s focus is on pathogens and bumblebees, but Looney and Koch asked her to join their survey of B. impatiens.
Abbotsford is part farm community, part suburbia. To meet Gillespie, I drive down a two-lane road lined with greenhouses and commercial blueberry crops and crowded with trucks, cars, and the odd tractor. “Oh, here’s an impatiens—she’s moving fast,” Gillespie says as we stand at a blackberry patch in a public park. I blink, and the bee is gone. We’re about a mile from the nearest greenhouse, which means the B. impatiens is either feral or a recent escapee.
“Once they built that greenhouse, that’s when I started seeing Bombus impatiens at one of my field sites, over there,” she says, pointing north toward the Fraser River. She’s been monitoring the same sites for eight years and rarely sees a B. occidentalis, although she’s spotted them on Vancouver Island.

A couple of other native bumblebee species whizz by before we stroll to a patch of native fireweed where bumblebees gulp an abundance of nectar from the bubblegum pink petals. Different plants offer different nutritional value, and research has shown that bumblebees thrive on a varied diet. But the intense commercialization of the blueberry crop in Abbotsford has simplified the landscape with thousands of shrubs. “Blueberries are attractive to bumblebees because there are so many of them,” says Gillespie, noting they don’t offer bees much protein. She equates the vast blueberry fields to big box stores, teeming with processed foods.
It’s hot, and the bees are fast. Gillespie points to a couple of B. impatiens flying deep into the flower patch. Then she chuckles: A bumblebee in front of us sticks its face deep into a bright pink blossom. It’s a B. vosnesenskii, the yellow-faced bumblebee that first lured me into the world of bees.
Earlier in the season, Gillespie collected a handful of B. vosnesenskii queens from the wild and placed them in a box designed for brood rearing, as a means of learning more about the behaviors of her study subjects. Koch and Looney did the same in a couple of different sites in Washington. Gillespie has had little success so far. “I think there’s something wrong with our queens,” she says, clearly frustrated, noting it could also be the lab setup. For publicly funded researchers and commercial breeders alike, figuring out how to rear bees in labs has been notoriously finnicky since the beginning.

Koppert, a commercial breeding operation based in the Netherlands, began raising B. vosnesenskii around 2007, and early results were mixed—the bee was not easy to domesticate. But eventually the company got it right, and commercial sales began in 2020. What did it get right? Who knows. Production methods are proprietary. “As you can imagine, we compete heavily with the likes of Biobest and other smaller local producers all across the world,” says Martin Wohlfarter, Koppert’s global regulatory affairs specialist. Fair enough: The pollination-services industry was worth $2.5 billion in 2024.
B. vosnesenskii could prove as lucrative as B. impatiens—it’s one of the two domesticated bumblebees allowed to pollinate crops in Washington and Oregon, both in fields and greenhouses. If British Columbia ever bans B. impatiens, it is likely that B. vosnesenskii and B. huntii will take their place.
But will using domesticated native bumblebees ultimately prove better than using non-native equivalents?
Well, domesticated B. vosnesenskii can potentially overwhelm habitat and outcompete other species, but more than one researcher points out that they’ll mostly stick with the “big box” floral department they’re released into. More worrisome is the spread of disease to wild bumblebees if an outbreak of a fungus, virus, parasite or bacteria hits a lab or two. What is known is that since the start of the commercial bumblebee breeding industry, infections caused by V. bombi, the fungus that sliced into B. occidentalis populations, have risen in wild species in western North America. Maybe bumblebees meet at a flower patch, alight on some of the same blossoms, each make their own little messes while sipping nectar and gathering pollen, and a pathogen hitches a ride back to a wild hive.
Felix Wäckers, head of research and development at Biobest, based in Belgium, is an ecologist and former academic. He joined Biobest 16 years ago, and at the time, he says, shipping pollinators around the globe was not acknowledged—at least by the industry—as a risk to native bumblebee species. Since then, he says, disease protocols have become more rigorous. For instance, scientists will breed queens for multiple generations to weed out potential pathogens from the original wild progenitors. Biobest has also bred native Japanese and South American bumblebees and has stopped selling B. terrestris to Japan and Chile. “I think as an industry, we have taken considerable steps over the last one and a half decades to minimize the impact,” Wäckers says. “That doesn’t mean that what happened with Chile is not a problem.” It also doesn’t mean other companies have stopped selling the non-native bees to Chile or Japan.
Colla, the conservation scientist, and her colleagues are calling for a “bumblebee clean stock certification program” across North America to reduce disease risk in captive production, which in turn would reduce the risk of infections in wild pollinators and other insects. As Colla points out, pathogen spillover is a regular occurrence between livestock and their wild counterparts—between cattle and bison; between farmed salmon and wild salmon; between poultry and wild birds.
My final bumblebee safari never pans out. I’m home, sick with a case of dramatic irony, infected with the Covid-19 virus.
Looney, Koch and their team head out without me to Whatcom County in Washington to check their B. vosnesenskii colonies. They’re doing well. Koch’s lab manager Tien Lindsay sends me photos. The mid-September day looks ablaze in foliage as the team checks a hive surrounded by the white and red blossoms of rugosa, a lovely flowering shrub from eastern Asia. Against an emerald backdrop of western red cedar striped with the white bark of an aspen, a scientist peers inside a white box. The yellow-faced livestock are hidden from the camera.
Unlike conventional livestock, bumblebees play a role in the agricultural system that is mostly hidden from consumers. It’s not intentional, just business: Bumblebees have become invisible in a system where profit comes first, food second and biodiversity barely registers. A handful of bumblebee species are tools, necessary tools for growers big and small, including the family-run greenhouse a couple miles from my house that sells the most exquisite heirloom tomatoes at the summer farmers market.
The corporate point of view isn’t wrong. An economy that hinges on one metric—money—rewards profit-driven behavior. But money is like a god that demands complete allegiance, leaving less space for the gods of small things, for the 260 or so other wild bumblebees that do not fit into today’s economic system but are likely impacted by it.
This is not the end of the story. Farmers have always been creative problem solvers. Change the goal, and farmers and researchers—highly skilled people—can transform the agricultural landscape into healthier ecosystems with space for all bee species. In fact, domesticating bumblebees led to a boost in biocontrol research, resulting in new ways to manage pests without relying solely on chemicals to massacre other life forms. Maybe change begins with an idea: to look at the world through the eyes of wild pollinators while acknowledging them as partners in our food systems. If we simultaneously reject the simplification of agricultural landscapes, we can create diverse food-producing ecosystems that encourage a variety of species that interact for the benefit of the whole.

Another picture in the batch that Lindsay sends me has a caption: “A Bombus vosnesenskii worker bee rests on Dr. Chris Looney’s finger. We were expressing our gratitude for her efforts and services.” Maybe change starts with that.
Travel and photography support for this story came from the Tula Foundation.
* Sheila Colla passed away on July 6, 2025. As a journalist, I only knew Sheila through a video interview and emails. She answered questions with clarity, patience and kindness and was always responsive. When we chatted many months ago, she was outside with her students, giving thoughtful answers to my questions, occasionally engaging with someone in the background, smiling all the while. She seemed unflappable. When I interviewed other biologists for this story, they often referred to Sheila’s work. From our brief encounter, Sheila came across as a matriarch of the bee biology world, a powerful, influential woman and scientist who cared deeply about the natural world. Please read about her remarkable sojourn on this corporeal plane here.
This story originally appeared in bioGraphic, an independent magazine about nature and regeneration powered by the California Academy of Sciences.