Speakers: Rich Hatfield, Senior Conservation Biologist, Xerces Society for Invertebrate Conservation; Becky Griffin, UGA Extension
Moderator / Host: Becky Griffin (co-host: Rich Braman)
Duration: 1:24:44
Series: Great Southeast Pollinator Course
Webinar Date: June 23, 2026
Introduction
Becky Griffin: I am extremely excited today because we are going to talk all things bumblebee, and I’m ready today, Rich. I have on my bumblebee earrings. I have on my Southeast Bumblebee Atlas shirt. I am really excited about this one. I am honored to introduce our first speaker. Rich Hatfield is a hero of mine. I’ve gotten to meet him in person a couple times. I’ve worked on several projects with him. He is all things bumblebees. He’s from the Xerces Society for Invertebrate Conservation, and you all know that is the premier society in the U.S. He manages all of the bumblebee work. He has a Master’s in Conservation Biology from San Francisco State, and his thesis focuses on what drives bumblebee species richness at the local and landscape level, which is a perfect topic. He’s investigated native bee pollination in California’s Central Valley, researched endangered butterflies from Colorado to the Pacific Northwest. And he’s an experienced teacher, and he does have a real gift for making conservation biology accessible. So I’m going to end the poll, and I am going to turn it right over to you, Rich.
Rich Hatfield: Great. Thank you so much, Becky. It’s an honor to be here. A real privilege. And I’m looking forward to today. So thanks for the opportunity. I’m going to share my screen here. Becky, I can see you. If you could give me a thumbs up and let me know if you could see that screen, that would be great. Yes. Super.
All right, I’m going to go ahead and get started since time is limited and there’s so much to talk about with bumblebees. So we’re going to dive right in. I’m going to spend, I don’t know, about 35 minutes or so today talking to you all about bumblebee ecology and conservation. I’m going to give you sort of an overview of what we know about the ecology and conservation, and then talk about what it is that you and I can do at home in our lives to make the world a better place for bumblebees. And then Becky’s going to follow up, I believe, with some more specific information about what we know that’s going on in the Southeast.
So with that, I’m going to just jump right in here. As Becky mentioned, I’m a senior conservation biologist for the Xerces Society for Invertebrate Conservation. We are a nonprofit. We’re based in Portland, Oregon, but we have offices all over the country, and we focus on the conservation of invertebrates and their habitat. And we have a number of different programs and ways we go about that. We do outreach like this. We also do citizen science, community science, direct science. We do advocacy. And we also do restoration on the ground. So great work going on by over 100 staff across the country, making a tremendous impact for this group of animals that we all care so much about.
We are a member-supported organization. So if you are a Xerces Society member, we really thank you. Your membership and support means more today than it ever has before. And if you’re not yet a member and are interested in supporting this important work for the conservation of this group of animals that are underspoken for out there, we would appreciate your help and support.
Why Pollinators and Bees Matter
But we’re not here today to talk about the Xerces Society, we’re here to talk about bumblebees and pollinators. And as you all know, since you’re here, you know that pollinators are incredibly important. For humans, one out of three bites of food that we put into our bodies comes from a plant that was pollinated by an insect, and usually that insect is a bee. And 90% of the world’s flowering plants are dependent on pollinators in order to reproduce. So 90% of the plant biodiversity and 33% of the food that we eat exist on the planet because of pollinators.
But I think an understated and misunderstood importance of pollinators is lost a little bit on their importance to wildlife as well. It’s not just humans that are dependent on food sources that come from pollinators. It’s also the vast majority of wildlife out there. Most wildlife has some sort of plant-based diet, whether that be berries, nuts, seeds, leaves, whatever. And most of those plants, 90% of them, are dependent on pollinators in order to produce those foodstuffs for other wildlife. So everything from small mammals and songbirds all the way up to grizzly bears are dependent on pollinators for their food sources. In addition to that, a lot of those animals that I just mentioned also use those plants for shelter in order to have a home. And pollinators are also helping to make a lot of that structure happen in the landscape. So pollinators are incredibly important. And I know I’m preaching to the choir here, but I also know that this is an important thing that we close the loop and make sure that we’re all on the same page moving forward.
Bees, of all of the insect pollinators out there — of which there are many: flies, wasps, butterflies, moths, and flies — bees are the most important of those, or the most significant of them, and that’s because they intentionally collect and transport pollen through the landscape. And they’re intentionally collecting pollen because it’s their main source, their only source of protein. And most bee species also lay their eggs directly on protein, or on the pollen. So it’s the food source for their developing young. And since bees are intentionally moving pollen through the landscape, they are very effective pollinators. Most other insect pollinators are just visiting a flower to get the nectar. And so they’re drinking the nectar and they might happen to pick up a couple grains of pollen along the way, but they’re not intentionally covering their bodies and moving it through the landscape. And so it’s that behavior of collecting pollen to move it around that makes them such great pollinators.
Bee Diversity and Bumble Bee Physiology
There are more than 20,000 species of bees across the world, and around 5,200 species of bees here in North America. And the Southeastern United States has around 500 species of bees. They come in all different shapes and sizes and colors. There’s literally a wildlife safari of bees almost anywhere you go in the world, and I would encourage you all to spend time in nature looking at these beautiful animals. Of course, we’re not going to talk about all of these animals today. We’re only going to drill down and talk about one small group of these native bees called bumblebees. And bumblebees have their own ecology. There are around 250 species worldwide. Here in North America, we have around 50 species of bumblebees. And in the Southeastern United States, there are around 16 species — or at least historically, there were around 16 species.
In North America, our bumblebee diversity is highest in our montane regions. So you can see in the part of the world where I live, in the Pacific Northwest, we have everything from oceans to high alpine mountains to deserts. So we have a ton of different ecologies out there and habitats for bumblebees. And so we can have as many as 29 or 30 different species out here, whereas the diversity is a little bit lower in the Southern Appalachians, down where most of you are, with only around 16 species — but still pretty good diversity for a small group of bees.
Bumblebees are incredible. They have amazing physiology. They have the ability to fly in really cold temperatures by regulating their own body temperature, something that most other insects can’t or don’t do. They have incredible cognitive abilities. They have abilities to learn, solve problems, learn from each other even, and communicate. And there’s been some recent studies that have showed their ability to solve novel problems is on par with what we’ve only understood for large mammals and primates, some of the “higher” animals that we’ve talked about before. So they have incredible capacity for learning and behavior, and we’re learning more and more about that every day.
They also have incredible morphological characters. They’re flexible. They have an incredible diet breadth, which makes them really important pollinators for a large group of plants. And then they have really cool behavioral adaptations as well that make them able to forage on a unique group of plants. Like you can see here, this is bottle gentian, whose corolla tube never actually opens up. And it’s only bumblebees that have learned how to pry open that corolla tube, crawl in there, get the pollen and nectar, and then move on to the next one to pollinate those plants.
The Annual Bumble Bee Life Cycle
The bumblebee life cycle is really unique. Most of what most people know in this world, or at least for social bees, comes from their understanding of honeybees. And honeybees have a perennial life cycle, so the queen lives for multiple years, and the workers alongside her. But the bumblebees have a very different life cycle. Instead of having a perennial life cycle, they have an annual life cycle. So queens only live for one year.
I’m going to turn on my laser pointer here. So if we start in the spring, a queen comes out of her hibernacula and she starts foraging for pollen and nectar to try to rebuild her fat reserves and get enough calories to start looking for a nesting site. Then she will fly around and try to find a place to build a nest. And usually that nest is in an abandoned rodent burrow underground somewhere. Rock piles and logs seem to be important. Sometimes these nests can be above ground in trees or in old bird nests. But usually they are underground or on the surface of the ground, sometimes under thatched grass or under a brush pile or a shrub or something like that.
Once she finds her nest, she starts building wax pots. And she fills those wax pots with pollen and nectar mixed together into kind of a cake. And then she lays her eggs directly on that cake. And then her eggs slowly develop, or they’re born as larvae. They look kind of like worms. And they go through several instars. And then they pupate and go through complete metamorphosis, just like a caterpillar into a butterfly. And then they emerge as winged adults. And that first group of winged adults that come out are the workers for the queen.
At that point, the queen then spends the rest of the year in the nest, laying eggs and tending to her young. And her workers are doing the work. They’re going out and collecting pollen and nectar from flowers and bringing it back into the nest to create resources for that queen to keep building her colony up. Once the colony gets big enough, with enough broods of workers out there, those workers will start bringing in enough resources, enough calories, so that the queen can start producing the reproductive members of the colony: the queens — next year’s queens — and the males. And the queens will continue to forage and use the nest as a source of security and safety, and the males leave the nest, and we believe for the most part they never return. Eventually, when the timing is right, the queen will find a mate, and she will mate with that male — usually only one male, although multiple males may try. And once she has mated, and again the timing is right, she will start looking for a place to build her hibernacula where she’ll spend the winter.
We don’t know that much about hibernacula, where bumblebees spend their winter or where they hibernate, but we believe that leaf litter and trees and north-facing slopes are probably quite important. And she digs her own hole in the soil underneath that substrate, and then spends the winter there, and then emerges the next spring, and the life cycle starts anew.
Cuckoo Bumble Bees
In addition to the life cycle that I just described, there’s also this incredible group of bumblebees called cuckoo bumblebees. And cuckoo bumblebees are just like cuckoo birds, in that they don’t find their own nest, they actually invade the nest of another species. So these species emerge later than our regular queens, and they fly around looking for existing nests. Once they find that nest, they will crawl into it, hopefully for them. And they’ll actually kill the foundress queen or take her over, and then use the worker caste that she’s already created to develop her own offspring instead of the offspring of the species of the foundress nest. And then all of the offspring from this cuckoo bumblebee are reproductives. They’re all sort of queen equivalents and males, and they will go out and do their thing. There’s about five or six species of cuckoo bumblebees in North America, and a few species down there in the Southeastern United States. It’s a really cool ecology, and we could get into more detail, but we probably don’t have time today.
Timing and the Egg-to-Adult Window
Just some caveats when we say sort of early spring and late fall: timing is really different for a lot of different species of bumblebees. Some emerge early and finish their life cycle relatively early. Other species start late and finish their life cycle relatively late. Other species start early and end late and have really long life cycles. So it’s really habitat dependent, it’s species dependent, and when we use words like spring or fall, it’s really just saying early season, late season, and what part that is really depends on what species you are talking about.
In the nest, when the queen is incubating and laying her eggs — this is what a bumblebee egg looks like in that wax pot on top of that pollen ball. This is what baby bees look like; so these are bee larvae over here. This is what a pupa looks like for a bee. And then they emerge as a winged adult. And that whole process, from egg to winged adult, takes four to six weeks. So a relatively long period of time for the queen to be on her own, especially in that early season when that first brood comes out. It’s a really challenging time of year where she has to balance her time between incubating her eggs and keeping them warm and feeding them, and then feeding herself to keep herself alive. So she’s spending a lot of time in the nest tending to her offspring, but then she also has to go out and keep bringing resources into the nest. And it’s a really sensitive time of year for her. And of course, it can also be a very wet and cold time of year, depending on what type of environment that we’re talking about. So really, really sensitive time of year in that early time, especially during those six weeks before the first worker brood emerges.
Buzz Pollination
As I mentioned, bumblebees have really cool and important physiologies. One of them is the ability to conduct something called buzz pollination. And buzz pollination happens for a group of plants that have something called poricidal anthers, where instead of just having the pollen loosely available on the anthers for any animal to come take advantage of, the pollen is kind of locked inside. And you can think about it almost like a salt shaker. So the pollen is inside of a tube, and the only way to get that pollen out is to shake the anthers vigorously. And here in this gif that you see, you can see this bumblebee has latched her mouthparts onto the base of the flower, and she’s vibrating her wings while she holds on to the anthers. And hopefully you can see at the tip of those anthers that there’s pollen just shooting out of the anthers and landing on the belly of the bee. And then she will fly somewhere and groom all that pollen off of herself and put it on her hind legs to add to those pollen balls that you see on her hind legs.
And so there are a number of plants, a lot of them in the family Solanaceae, that benefit from buzz pollination. Around 8 to 10% of the plants on the planet benefit from buzz pollination. And this is something that really only bumblebees, and maybe a very small handful of other native bees, do. Honeybees won’t perform this action. And so the plants that benefit from buzz pollination don’t benefit from honeybee pollination. And here’s a group of plants that do benefit from buzz pollination: as I mentioned, the Solanaceae, which includes like tomatoes and peppers and eggplants — those are a lot of our high-value crop plants. And so bumblebees are very important for crop pollination, in addition to wildflower pollination.
Nesting and Overwintering
Bumblebee nests, as I mentioned, are typically below ground, but they can be found above ground. Here’s two photos in the bottom left of nests that have been found in the wild, and then researchers, including myself, have tried to dig up to learn more about their nests. Sometimes these tunnels can be meters long. The one on the lower left there is a nest that we dug up in central Oregon, where the nest entrance was almost eight meters from the nest ball underground. So it required a lot of excavation. And so usually these are actually old rodent burrows. So the rodent has created this long tunnel system, and the bumblebee queen flies in there, finds where the cavity of the nest is, where there’s insulation and stuff from that rodent, and then builds her nest in that ball. So the nest itself can be quite far from the nest entrance, and that’s important to think about.
Bumblebee overwintering, as I mentioned, we don’t know that much about it. What we do know is, as you can see here, this is an example of a queen common eastern bumblebee likely excavating her own hibernacula. So it looks like she’s in some mossy area with some loose soil, and she’s in there pulling that loose soil out to create a place for her to spend the winter. And it’s usually about an inch or two below ground. So she gets insulated there from extreme cold, but also doesn’t get too warm. We don’t know a whole lot about bumblebee overwintering, especially at a species-by-species basis. We’ve found common eastern bumblebees doing this, but I’m not sure anybody has ever found, say, a rusty patched bumblebee doing this. And so there is still a lot to learn about bumblebee overwintering, and it is an active area of inquiry. And we of course don’t know anything about habitat associations or survival rates or a whole bunch of other things that we still need to learn about this.
And one of the reasons this is important is that there are some species of bumblebees that aren’t doing very well on the landscape — and we’re going to talk about that in a little bit here. And, you know, we focus so much of our effort for pollinator conservation on putting flowers in the ground. But there’s a chance that flowers on the ground aren’t the limiting factor. It could be that overwintering sites, or the disturbance of overwintering bumblebees, is a limiting factor in their reproductive success. And so until we learn more about their ecology, it makes it a little bit harder to enact on-the-ground conservation actions that are most effective. That does not mean that we shouldn’t keep putting plants in the ground to feed pollinators, because we know that they need them. But we also need to keep learning about what the most important aspects of the bumblebee life cycle are for their conservation and reproductive cycles. And so along those lines, that sort of is a really brief primer on bumblebee ecology.
Conservation Status and the Endangered Species Act
We’re going to now talk a little bit about bumblebee conservation, and then talk a little bit about what’s going on in this world and then what we can do about it. Around a quarter of the bumblebees in North America are facing some degree of extinction risk. This is an analysis that I co-led with a number of colleagues here in North America for the International Union for the Conservation of Nature, the IUCN Red List, where we looked at the extinction risk of all bumblebees in North America, and we found around a quarter of them were facing some degree of extinction risk. I’ve circled the species that are in the Southeastern United States in black on here. So there are around six out of the 16 species in the Southeastern United States that are facing some degree of extinction risk. So that’s a relatively high proportion of the bumblebees that are native to the Southeastern U.S. that are imperiled. And so there is a lot of work that we do need to do.
There are three species that have been added to the Endangered Species Act officially. The rusty patched bumblebee, Bombus affinis, was listed in 2017. And that species is native to the Southeastern United States, or at least some of it. Franklin’s bumblebee was listed in 2022. It is only native to southern Oregon and northern California, a very small range, so not a species that you all would have a chance to see, but it was added as an endangered species. And then Bombus suckleyi, the Suckley cuckoo bumblebee — one of those cuckoo bumblebees that I talked about earlier — was proposed for endangered species status in 2025. So there are some officially listed species, indicating that threats of extinction are real for this group of animals. And it’s really not just these three. There are a number of other species that are in the Endangered Species Act pipeline for protection. So lots of attention being paid to bumblebees right now.
Why Bumble Bees Are Declining
So what’s going on? Why are bumblebees declining? There are a number of different factors. There’s no single smoking gun, or at least we haven’t found one yet. What we believe as practitioners is that there are a number of different threats on the landscape that are interacting with each other and likely compounding with each other: habitat loss, pesticides, pathogens, competition with non-native commercial bees or even native commercial bees in some cases, and climate change. And all of these things are individual factors, but they’re also compounding. And what I mean by that is, let’s say you have an animal that’s suffering a little bit from habitat loss and has to fly further to get its resources in order to feed their young. And then all of a sudden we throw in some pathogens that were given to them. And because they’re already stressed and working harder, they’re more susceptible to disease from those pathogens. And so that can make things worse. It’s no different than us going about our daily lives. We get stressed out at work, and we get stressed out because of our kids or whatever it is, and then all of a sudden our immune system — we’re going to get in a lot of trouble and we become more susceptible to the flu or whatever disease comes our way. The same thing is likely happening in bee populations. And I just use that as a hypothetical example, but hopefully that helps you understand what I’m talking about.
Habitat Loss
And so just going through each of those threats individually here real quick: because of that long life cycle that I talked about, right — a bumblebee queen, it takes five or six weeks just for the first workers to emerge, and then to get the reproductive members of the colony is going to be at least another five or six weeks. So bumblebees need at least 12 weeks, and likely much more, closer to 20 or 25 weeks, of flowering resources in order to reproduce. So they need that flowering resource from early spring through late fall in order to support their life cycle. And a lot of habitats that used to provide this — mostly the grasslands and prairies of North America — have been converted to agricultural lands and/or urban or suburban habitats. And those habitats, while they might provide some flowering resources, an agricultural field is likely only to provide flowering resources for a week or two. And then there’s so much grass out there in the landscape that’s not providing habitat for bumblebees or really almost any other animal on the landscape. And so these have become more or less deserts for bumblebees.
Pesticides and Neonicotinoids
Of course, pesticides are also a major threat for bumblebees and other pollinators out there on the landscape. And of particular concern are systemic insecticides. And you may have heard the term neonicotinoid, which is a group of chemicals that’s nicotine-based that are highly toxic to bumblebees and other bees. And the problem with these neonicotinoids and other systemic insecticides is that the product is actually water-soluble and absorbed by the plant, and then it’s expressed in every tissue of the plant. So you can apply it at the base of the plant, and then it’s absorbed into the roots. And then everywhere water goes, this chemical goes, and that includes the pollen and the nectar. So every time a bee eats pollen from a plant that’s been treated with one of these systemic insecticides, it gets a microdose. Same thing with the nectar. It’s getting a microdose of these insecticides, which has what we call sublethal effects. It affects their ability to navigate and eventually lowers the reproductive rate. And so these things are incredibly toxic. They’re very long-lived. They can accumulate in the soil. And some studies have shown that even after a single application to a woody plant, they’re still persistent seven years later. So they’re incredibly long-lived as well. So really, really concerning. And they’ve been implicated in the decline of several species of bumblebees. This is a study that I co-led for the western bumblebee, Bombus occidentalis, where we found that where there was increased use of neonicotinoids, we saw a decrease in predicted occupancy of the western bumblebee, which is a species out here in the Western United States.
Pathogens
In addition to pesticides, pathogens are also a major factor. There’s a fungal pathogen called Vairimorpha bombi that was actually amplified and spread by commercial bumblebees in North America and led to the decline of all of the species that you see here on the screen. And if you remember, the rusty patched bumblebee here and Franklin’s bumblebee are two species that were added to the endangered species list. So this is a factor that has been implicated in really steep declines for a couple of our high-profile species here in North America.
Competition with Honey Bees
In addition to all of that, competition from honeybees is also a major factor. I don’t know if it’s a major factor — I shouldn’t say that. It is a factor, though, particularly in our shoulder seasons when there aren’t as much flowering resources on the landscape. One honeybee hive has 15,000 to 80,000 mouths to feed in it. That is a lot of pollen and nectar that they’re taking out of the landscape that could otherwise be used by bumblebees or other native bees. And bumblebees and honeybees have a lot of resource overlap. They’re both generalists that use a lot of the same plants. And honeybees are wonderful, no doubt about it, but they are not in danger. There are probably more honeybees on the planet now than there ever have been in history. And so when we talk about who those resources should be available to, in my mind, we should make those resources available to our native bees and make sure our native bees are able to help keep our native plants and native landscapes healthy.
That doesn’t mean you shouldn’t be a beekeeper, but if you are a beekeeper, the reason to do it is because you get honey out of the deal, and they’re beautiful animals that there’s a lot to learn from. But it’s not conservation. It’s animal husbandry. We have chickens, we have cats, we have dogs, and there are good reasons to have all those things, but we’re not practicing mammal conservation by having dogs and cats, and we’re not practicing bird conservation by having chickens. We just like to have chickens and cats and dogs. And having honeybees is no different than that. There are great reasons to do it. Just do it for the right reasons, and don’t do it for conservation.
Climate Change
Climate change is also a major factor here. It is creating mismatches between pollinators and their flowers. It’s stressing bees out. It’s reducing reproductive success. Climate change is just a fact, and it’s impacting every species on the planet. And it makes all of those other threats that I’ve already talked about even more of a factor than they were before.
What We Can Do at Home
So what can we do about it? One of the great things, I think, about bumblebee conservation and pollinator conservation in general is that we’re still, for the most part, in a “build it and they will come” scenario. We have amazing opportunities to do things for pollinator conservation, and when you do something in your backyard, you’re almost certainly going to see impacts immediately. So there are real, concrete things that you can do to help pollinators today, tomorrow, that are harder to see for something like polar bear conservation, right? Which is still important — we should still be working on saving the polar bears, but it’s harder to do in your backyard. This is actually something that you can do something about and see impacts almost immediately.
So what are those things that we can think about doing? I’ve mentioned today some uncertainty about bumblebee ecology and conservation. And I think that’s true. There is uncertainty. But if we sit on our hands and wait to do anything until we know the perfect actions out there, it’s going to be too late. We’re starting to lose large groups of invertebrates on the landscape, and the time to act is now. So even if it’s not the perfect action, putting flowers on the landscape, stopping the use of some of these toxic insecticides at home, are going to make an important difference and give us the time we need to figure out what the more effective actions might be. So don’t let perfect be the barrier of good. Go out there and do good, and do good things in your communities.
For the most part, what we really want to do is focus on building habitat. We want to put food on the landscape, shelter on the landscape, connect those things, and then stop using these toxic insecticides. Plant diversity is nutrition for bees. Different flowers have different protein contents, have different fat contents, have different types of sugars, have different types of secondary compounds. So putting that whole suite of flowers in the landscape for bumblebees and other pollinators is incredibly important. So putting that diversity of plants out there is super important for bumblebees. Create diversity, create heterogeneity. Especially in the early spring, plant flowering trees and shrubs that flower really early. They’re going to help those queens found their nest. Likewise, the late fall, when those queens are mating and trying to build up their fat reserves to survive the winter — that’s a really important period as well. So planting plants like, in this case, goldenrod, that bloom super late. Milkweed’s another good example here that blooms late, so that we can get the fat reserves that those animals need to survive the winter.
Make sure when you’re planting plants for pollinators and bumblebees that you’re selecting real flowers. A lot of horticultural varieties don’t have any pollen or nectar in there, so try to choose native plants. It’s the best way to go for bumblebees. And that will also support our butterflies and moths and other pollinators out there. We also really want to try to avoid treated nursery plants. A lot of larger nurseries actually pre-treat their plants with these systemic insecticides that I’ve already talked about. And so some people buy plants and put them in their yard and they’re already toxic. So you really want to be careful and talk to your nurseries about the type of plants that you’re buying, and make sure that they’re not pretreated with some of these chemicals that we’ve talked about. If the nursery that you’re using doesn’t know the answer, go to a different nursery. It is really what it is. We do have resources on our website that can help further, including this relatively new fact sheet that we have called Buying Bee-Safe Plants.
So that’s food — basically putting food on the landscape. We also want to create shelter. So, places for bumblebees to overwinter and nest. And this is really just your chance to be a little bit lazy in your yard. Create some messy areas of brush piles and rocks and bunch grasses, and creating heterogeneity on the landscape. And the same thing for overwintering: leave some leaves on the ground underneath trees. Leave some of that pine needle duff, especially on northeast-facing slopes and in shady areas. Create as much heterogeneity as you possibly can, and you’re going to do good things for bumblebees. And doing this at any scale is important. You don’t have to do it all. Even if you live on a third-story apartment building, you can still put a couple of plants on your porch. And I can almost guarantee you that pollinators are going to find it up there. So any scale is really important, but we need to do it everywhere so it’s connected and we can help these pollinators keep the genetic diversity and population sizes that they need to be healthy.
Community Science and the Bumble Bee Atlas
Xerces has a treasure trove of resources on our website of fact sheets. They’re all available for free, PDF downloads. I would encourage you to go to xerces.org and check those resources out.
In addition to all of that, community engagement is a big part of this. Xerces is running a project called the Bumblebee Atlas, where we’re encouraging people to go out and collect data, which is helping us to close some of these information gaps. So participate in a community science project. The project that Becky Griffin is also running, the Southeast Pollinator Census, is fantastic, and you should also participate in that, and I think she’s going to talk more about that in a minute here.
But just to give you a sense of what this looks like: so Xerces, as I mentioned, has staff all over the country. Over the last several years, our staff have collected 4,000 bumblebee observations that we’ve contributed to bumblebee conservation. If you left it to the 10 of us that are out there collecting bumblebee information, it would take forever for us to cover the entire country. But when we enlist the public and we train you how to go out and collect data for us, we magnify our impact hundreds of fold, essentially. And the public has helped us gather over 200,000 observations throughout the United States, making a real difference for bumblebee conservation across the region. You are helping tremendously, and your impact really, really matters. And so the Bumblebee Atlas is a great way to have a positive impact on this. Connect with your community. Go out and conduct real surveys that are closing information gaps and making a difference for bumblebee conservation, in addition to everything else that I’ve talked about.
We have a project going in the Southeast — in Tennessee, North Carolina, South Carolina, and Georgia. Over the last three years, we’ve collected 6,200 observations on 12 species, and more than 300 people have conducted surveys for us. We hope that you will join us and become a member of this project. And you can go to bumblebeeatlas.org to learn more about this and how you can get involved.
And with that, I’m going to say thank you very much for your attention. I know that I probably talked too fast, but there was too much to get through, and I didn’t want to cut any slides out, so I packed it all in. So hopefully I didn’t make your brain spin too much, and I’m happy to answer any questions if there’s time.
Questions and Answers with Rich Hatfield
Becky Griffin: All right, yes, we have a few questions for you, but I also wanted to say that I’ve been a part of the Southeast Bumblebee Atlas since it started, and I collect every year. I actually have Friday scheduled to do some collecting and get some data in. I really enjoy it. Bumblebees are my favorite, so definitely, if this is something you’re interested in, you want to learn more about bumblebees along the way, it is a great project. And when we post the recordings, I will have a link to everything that you need to become involved.
All right, so we have a few questions. Rich, can you tell which is a queen bee versus a worker bee if you’re just out in the landscape?
Rich Hatfield: It’s hard. I will say that once you’ve put your 10,000 hours in and you’ve seen hundreds of every different species, you can get a pretty good sense of it. But there’s a pretty narrow gap between a large worker and a small queen. And particularly sort of midsummer, when those large workers are out and the new queens are starting to emerge, it can be challenging, and there’s no surefire way to tell, “Oh, that’s definitely a queen,” or, “Oh, that’s definitely a worker.” But you can get it once you start seeing different species and knowing what their size and personalities are. You can get a pretty good sense of it, but it’s not simple.
Becky Griffin: No, I agree with that. We have somebody who wants to know, is the cuckoo bumblebee the same species, or can any bumblebee species disrupt another bumblebee’s nest? Cuckoo bumblebees are a species. Like, there are…
Rich Hatfield: It’s mostly a lifestyle that evolved for those species. And so they always have that strategy of invading other species’ nests. That’s what makes them cuckoo bumblebees. There are some species of bumblebees that have cuckoo-like behaviors, but it’s not — you wouldn’t find it, like, in the Southeastern US. This would happen normally, like, in the high alpine or in the high latitudes where the growing season is so short and competition for nesting sites is so great that you might find that interaction happening there. And there is one species that’s adapted that kind of lifestyle that’s not a true cuckoo bumblebee. But for the most part, in most parts of North America where we visit and look at bumblebees, it’s going to be a particular species that has that life history that we talked about.
Becky Griffin: Okay. Laura would like to know, how does a queen incubate her eggs, and how many eggs might she lay in a season?
Rich Hatfield: Great question. I mentioned their unique physiology and their ability to regulate their own body temperatures. And so queens are doing that when they’re incubating their eggs. They’re in their nests. They can actually detach their wings from their flight muscles and then vibrate their flight muscles, which raises their body temperature. And that action creates heat. And that heat is what they use to incubate their eggs. And they need to keep those eggs at a temperature so that development proceeds. As you can imagine, sitting there and shivering is resource intensive. It takes a ton of calories. And so for the queens to be able to do that, they also need to go out and forage and keep their calorie stores up high enough to do that. So it’s super resource intensive.
Becky, there was a second part to that question, and I got so excited talking about that I forgot it. How many eggs should she normally lay in a season? Yeah, this is another thing that’s probably habitat-specific and also species-specific. Some species have super, super large nests. The common eastern bumblebee is one of them. They can have nests of, like, up to a thousand individuals probably. And there are other species that, again, live in areas with shorter growing seasons that might only have 50 individuals in the whole nest. So the number of eggs can vary from the tens to all the way up to over a thousand.
Wow. Yeah. All right. Let’s see. Is there any imaging that can be used to find and see nests underground? That’s a good question. We’d love to be able to find more nests. Using infrared technology could be something that you could look at in terms of finding it, and who knows what will evolve in terms of the ability to have sort of live X-ray — although that sounds like a lot of radiation to be throwing into the world. As far as I know, using infrared technology or heat-seeking technology to try to find nests has not been used or been successful, but it’s certainly — I’m open to almost any opportunity at this point. One of the things that we’ve been trying at Xerces, and that has been growing in popularity, is actually the use of radio telemetry to try to find nests. So we’ve been actually attaching little antennae, radio antennae, onto bumblebees with glue, and then following them using radios back to their nests. And our crew here at Xerces was able to find a couple of nests a couple of summers ago doing that. And there’s been new technology — you may have all seen it in the monarch world, where they’ve been actually attaching these new super-light solar tags that have allowed us to learn so much about monarch migration in the last year or so.
Becky Griffin: And so that technology is being tried out this summer as well. So that’s another thing that’s being used to try to find nests. That’s exciting. Yeah, it’s cool. All right, we’re going to give you a break and let you kind of have a drink, and I’m going to take over a little bit for you.
Rich Hatfield: That sounds great. I’m looking forward to your presentation. Thanks so much.
Becky Griffin: Thank you. All right, I’m going to share my screen here.
Becky Griffin: Bumble Bee Anatomy and Identification
Becky Griffin: All right, Rich, will you give me a thumbs up? Let me know if everything looks good. Looks great. All right, excellent. So I am honored to be not only the co-host, but a panelist today, to talk about my very favorite insect, a bumblebee. And in my presentation, I’m going to talk a little bit about — well, I’m going to continue the talk on what we can do, how we can make lives a little bit better for bumblebees in the Southeast. I’m also going to talk about how we can be better counters of bumblebees during the Great Southeast Pollinator Census. And lastly, I’m going to get you all to fall in love with bumblebees as much as I am, and I’m going to teach you why they are outstanding pollinators. So with that being said, let’s go.
The Mountain Research and Education Center
I am saying hello to you today from Blairsville, Georgia. I work at the University of Georgia’s Mountain Research and Education Center. This is a 400-acre center where we do a lot of agricultural research. And one of the things we research is apple trees. And let’s say we have about 1,800 apple trees on the property, and just for math’s sake, we want 100 apples per tree. Each of the blossoms that you see here has to be visited by a pollinator eight times. That is a lot of pollination visits. And most of our pollination visits are actually done by native bees. So when the blossoms are blooming, I’m out there looking for what bees are actually doing the pollinating and getting a lot of really nice pictures. So we’ve got Rich in Oregon and Rich Braman in Griffin, Georgia, and I’m up in the mountains today.
I have loved bumblebees my entire life, and I’ve been lucky up here to actually get to do some research on bumblebees. We’re looking at how some of the things that are sprayed on apple crop and blueberry crop affect bumblebees. And so I get to do that fun thing. So here I am out, actually in February, trying to do some bee collecting. It was a lot of fun. It’s always fun to work with and see these beautiful insects.
Insect Anatomy and the Pollen Press
All right, we’re going to do a little bit of entomology, because, as I mentioned when we first started this course, the purpose of this course is to do a little bit more of a deep dive. I want y’all to learn a little bit more entomology — obviously you want to learn a little bit more than you would get, let’s just say, when you’re learning just how to count for the census. So we’re going to start with this. We’ve got three sections of an insect. We have the head, where you have the eyes, all of the sensory organs, the antennae. We also have the thorax in the middle, and that’s where the locomotion happens. That’s where the wings are attached. That’s also where the legs are attached. And then at the end, we have the abdomen, where you might have a stinger if you are female.
But I want to give you a little bit more information about this. So, of course, only females sting. If you are a female, your antennae are going to be a little bit different length. You’re actually going to have one segment shorter. You’re also going to have one segment shorter in your abdomen, and we call these segments tergites. Now, I want you to pay attention right here. This is the pollen press, right in here. And this is a very interesting part of the bee, and we’re going to examine it a little closer.
Now, remember when Rich was talking about how bumblebees are really great because they’re amazing pollinators because they have a biological need for pollen and nectar — whereas many of our pollinators, let’s say butterflies, they’re mostly interested, of course, in the nectar. They’re not moving as much pollen around. They have no real need. But I also want us to think about the fact that pollination, and the resulting fertilization, is almost accidental. So the bee is going into the plant looking for pollen for herself and her young and her nest. She’s not going in there saying, “Man, 4th of July is coming up. Becky really likes watermelon. I gotta get out there, get some watermelon for that woman.” Nope. It is a fact that this pollen gets moved around, and if it gets moved around to the right place, fertilization happens, and then the survival of the species. So for a plant, pollination is imperative for that survival of the species. And for bees, the plants are important to give that food source, that vegetarian protein. So it’s a fun topic to study, the evolutionary dance between bees and plants.
And I highly encourage you, when you’re sitting around waiting on your kids to get out of school or the doctor’s appointment to happen, maybe do some Googling on your phone. I think you will find it extremely fascinating. When we looked at our entomology slide, I pointed out the pollen basket, or the corbicula. And this is a very interesting part of the bee here. Only the females have it, because only the females are caring for the nest. So if you’re seeing these bees fly around with this pollen basket, you know that you’re looking at a female. And not all bee species have this. Honeybees do, and bumblebees do. Other species of bees may have other ways to move pollen. But it makes sense for nature: if Rich was talking about an eastern bumblebee maybe even having a thousand babies to take care of, that’s a lot of pollen that needs to be brought back to the nest. So these pollen baskets make it a little easier. The bee will actually take a break on a leaf or just sit on a rock and groom herself and tuck that pollen in that pollen basket, so she has a lot to take back to the nest. But luckily for nature, she’s not perfect at this, and she’s not going to get all the pollen in that pollen basket, and some is going to be left on her body for the important pollination. And remember, pollen is protein and nectar is a carbohydrate source.
So I have a little video here, and I want to show you — I want you to note, this is not on a fast speed. This is normal iPhone speed. How frantic these bees are to collect this pollen on this St. John’s wort. They’re serious about it, and they’re very deliberate in their movements, and that is really important to consider when we’re talking especially about bumblebees. Now, there’s some other bees mixed in here. There’s a few carpenter bees I see, but primarily we are looking at bumblebees, mostly the eastern bumblebee, going nuts for St. John’s wort.
Habitat Is More Than Flowers
Now, why? How do they know exactly what’s going on? These are extremely smart. Rich mentioned that they have great cognitive skills, and we’ll talk a little bit more about that in a minute. And Rich also showed us this slide, which is funny that we chose the same one, but what I want you to do now — he’s gone through the life cycle — I want you to think about this in terms of your yard. Now, we can talk about floral resources, and we know how important it is to have diversity in our floral resources. We know that it’s important to have early spring blooming things, and then going through the fall, we also know that Georgia, in the Southeast, has an amazing collection of fall native wildflowers. But if we’re talking about true habitat, we’re not just talking about floral resources. We’re talking about where the nest is going to be built. Where are these queens going to overwinter? And if you’re bagging up your leaves, you’re actually probably bagging up some bumblebee queens. If you are cleaning all of the twigs and all of the limbs that may fall during storms, you probably are cleaning up areas that the bumblebees would like to nest. So floral resources is not the entire picture for habitat. So if you really want to build up populations of bumblebees in your yard, think about this slide and all the things that you really need to do to make that happen for those sweet bees.
And here’s a picture I had of a bumblebee nest. This is under a bunch of moss. So they’re kind of hidden — although I have actually found them in old toolboxes. You know, when you open up a toolbox and there is that empty spot in the middle, I guess that looks a lot like an old abandoned rodent home. So more than once I have found a bumblebee nest in there as well.
The Eastern Bumble Bee
All right, so when we talk about what we’re seeing now and what we’re going to see during census time, the most common bee that we see is the eastern bumblebee, Bombus impatiens. This is a picture of one right up here. It is the most common bumblebee in Georgia. They have nice long tongues, which is awesome, because that means they can find nectar in a lot of flowers where maybe the nectar is far away from the opening. And I want you to really pay attention to how much hair these bees have. That is a very important part of their biology and their morphology, and another reason that they become great pollinators.
Now, if you want to learn more about bees and study bees, this little diagram here kind of shows you how we mark them. A lot of our bumblebee identification is on their markings or their colorings. And here we see the eastern bumblebee. We see up here that her thorax — she has a lot of yellow hair with a little bit of black in the middle. And her tergites are the segments in their abdomen. Her top one is nice and yellow. Now, I will caution you, if you do really get into this and you’re looking at these diagrams, they’re not always 100% accurate. The males may look different. The queens may look a little bit different. In different areas of the country, things may look a little different. But it’s definitely a great starting point, and as you learn your bumblebee ID, it’s a great way to really start doing that. So this is the eastern bumblebee. About 70% of the bees that I see, bumblebee-wise, are those eastern bumblebees. So just remember, Bombus impatiens, and you can go home and impress your family at dinner time. That’s our most common bee.
Long Tongues, Learning, and Flower Fidelity
Now, I mentioned their long tongues, and this was a picture I took the other day. Look at that long tongue. Having a nice long tongue is going to help that bee, like I said, reach a whole lot of nectar. It’s going to help that bee get even more pollen. We do have some short-tongue bees, and they’re not going to be as efficient in that. Now, another thing to mention is — we talk about how smart these bees are. These bees will figure out a flower. Let’s say they’re figuring out a mountain mint. So they’re going to go and puzzle it out. They’re going to find out, where is that nectar? Where is the pollen here? How do I get it? How do I get it easily? How do I get it quickly? And remember back to the St. John’s wort video. Those bees got on that flower. They knew where they were going. They knew how to get that nectar, how to get that pollen. Once they learn a specific morphology of flower, they are more likely to visit that flower again.
Now, that makes it easier on the bee to get the resources that the flowers have provided. It also means that is an advantage for pollination. If this bee visits a mountain mint and then a clover and then an apple tree and then a hyssop plant, there may be some pollen moving around, but that pollen is not leading to fertilization, and not meaning that we’re getting plant seeds or even fruit. But if these bees are learning that flower morphology and visit that same type of flower over and over, not only are we moving pollen, we also are resulting in fertilization, which is the big goal there. So that’s kind of an important thing to know about our wonderful bees.
Size, Strength, and Generalist Foraging
Here are two Bombus impatiens. Again, we see that yellow on that first abdomen segment. And look how they fly. They fly like big teddy bears. And they’re big. And one of the neat things about them is, there’s some plants that produce pollen by the bucketloads. They’re going to let wind take it. They’re going to — whoever wants it, come and get it. We’re just hoping that if we produce a lot of pollen, some of it will end up where it needs to be. And there’s some plants that are stingy with their pollen. Maybe it’s sticky. Maybe, as Rich mentioned, it’s kind of enclosed in the flower. Well, that means that that plant is going to be very picky about who moves that pollen, because there’s just not a lot of it. These bees are big and heavy. They can open lips. They can open the lip of a snapdragon. They can get inside some of these other flowers that other bees just cannot access that pollen. So that makes them also efficient for a lot of the pollen movement.
A lot of our bumblebees are basically generalists. They’re going to not necessarily favor one type of flower over another. They’re going to use what is available — unlike things like squash bees and blueberry bees, who really like that family of plants.
Bee Hair (Pile) and Electrostatic Pollination
So again, we’re going deep, y’all. Stay with me. We’re going deep on these insects, and we’re going to talk about bee hair. All right. And the scientific word for bee hair is pile. So again, another cool fact that you have. And I want you to consider this wonderful bumblebee on this side with her long tongue. And then on this side, we have a nice little metallic sweat bee. Now, this bee is beautiful. It’s really pretty. You can see on its legs there’s some pollen. So this bee moves pollen on special bristles on her leg. She doesn’t have a pollen basket. That may indicate that her nest is not quite as big. She doesn’t need to bring a lot of pollen. She doesn’t have a lot of hair on her body, and so a lot of pollen is not sticking. It’s not staying on her body. And here, with this bumblebee, we’ve got pollen on her face. There’s pollen on her legs, all over her body. She has pollen all over her. And that bee pile, that hair, not only helps them stay warmer in cooler climates, it really does help them move pollen along.
And this is a picture I took up in Athens. And I found, doing a little research, that as these wonderful bumblebees with all this bee hair and pile fly through the air, all of that pile becomes positively charged. You remember taking a balloon and doing it on your hair, so we have kind of an electrical charge. So what happens is, as this bee gets in a plant that has maybe negatively charged pollen — I call it the “whoop” effect — that bee does not have to do a lot of work to get that pollen to stick. It is just naturally electrically attracted to that bee. And this bee will probably leave that flower a little pollen-drunk, and is going to stop and groom herself and tuck that pollen in her pollen baskets. But that hair does play such an important role in them being such amazing pollen movers.
Branched Hairs
This is a photo from a transmission electron microscope. And these are hairs that you see from a bumblebee, and they’re branched. All right, and this is pollen. So branched hairs mean that, as that bee is flying along, that pollen is a little more trapped. All right, it’s not going to fall off into the grass or fall off into the water as it’s flying. It’s going to stick around in that hair until the bee lands and moves around, and maybe rubs off on some stigma or some female parts to move that pollen. So again, another way that these bees are just made to move a lot of pollen.
Wings
All right, y’all hanging with me? We’re going to keep going and talk about wings. All right. These wings are delicate. Look at this close-up here of these wings. Bees have four wings, where flies have two. And why that is — bees are a little more evolved on the evolutionary scale. And as that bumblebee opens up those front wings, they attach to the back wings, and they have a big surface area that kind of helps them fly. But you can see how delicate they are. And these bees are flying far, and they’re using those wings to keep them up and mobile. And when you notice them flying — you know, we’re teaching kids about wings, we teach them that, oh, a bird flaps their wings up and down, kind of in the same plane. Bees are not like that. This bumblebee will use those wings forward and backward, sort of like we have a socket in our shoulder to move our arms. Bees have something similar.
So we’re going to revisit. And this is the St. John’s wort plant again. But I did some slow-motion video here, so you could see — pay attention to the wings here. All right, we’re in slow-mo now. So you can see those wings are not staying in the same plane. They can move forward and backwards and up and down and 90 degrees, whatever the bee needs to keep them balanced on that flower. It’s amazing what those little delicate wings go through, working that plant that she knows very well. Yeah, I love this too. I have a heart for this too. And here comes another one. Look how those wings balance that bee and allow that bee to land right on that plant. Again, there’s no flapping here, but really precise movements to keep that bee steady. All right. Very nice. Very cool.
All right, so we’re going to talk a little bit about — this is a bee flying. I took this the other day when I was doing some bee sampling. I’m going to slow it down, because I want you to watch the bee take off. It’s like a helicopter. I’m going to move it really slowly. You can see the wings are lifting the bee straight up. Those legs are falling behind. Then the wings move forward, and then start carrying the bee. Legs are still hanging loose. And there the wings are. I mean, that’s pretty amazing. Well, I’ll show you a little bit more of that, because I think that’s just really phenomenal — a slow motion of a bee taking off. Just like a little helicopter, and then the wings move forward. So bees are just amazing, and it does show you again those delicate wings. So it won’t surprise you to know that a cause of death of bees is their wings wearing out. And you can see, this particular bee — when the bee first eclosed and was a new bee, all this was a nice clean edge, and now they’re wearing out. It just amazes me every time I see one fly, and all the flying they have to do. So the wings are important. They help get the bee where it needs to be. They help stabilize the bee as the bee is foraging for pollen. A lot of really cool movements go on because of the way those wings are made for that bee.
Legs and Tarsal Claws
All right, y’all hanging in there? Gonna talk about legs a little bit. And this is what the pollen press looks like when it doesn’t have pollen in it. It’s nice and flat. Excuse me — it’s nice and flat, so it’s not impeding flight aerodynamically. And look at all the hair on this bee’s leg. I want you to notice the bee feet, or the tarsi. Excuse me, I’m getting excited here. Pay attention especially to this one. Does this look familiar to anybody? Anybody out there a rock climber? Doesn’t this look a lot like a grappling hook? And these feet allow that bee to, again, dig deep into plants. It allows them to hang upside down on your screens at your house. But it also allows them to maneuver into plants to find that nectar, find that pollen. It’s important as they’re digging there for overwintering, that type of thing. All right, you can see how that bee used her tarsal claws to really get in that squash blossom and really find out where it needed to go.
Faces, Eyes, and Vision
All right, we’re going to talk a little bit about their faces. This little cute bee has pollen on her face. And remember, her face has her sensory organs. So she’s got her antennae here. She has two big eyes on the side of her face. And then in the middle, she has three tiny eyes called the ocelli. And scientists think that those ocelli are what help her navigate and fly in a certain way, so she’s not tumbling around or upside down. But the face and all these sensory organs help them not only find mates and find their way home, but also to find good food sources.
And it’s important, when they’re finding food sources, to understand what they see. And I think this is fascinating. So bees see in a little bit of spectrum difference than we do. They don’t see red. Red looks black to them. They see lots of blues and green. So on this side are what we see, and when we pick our flowers, a lot of times we’re picking what looks pretty to us. And here is what a bee sees color-wise. And here is really what the bee sees, using all of their photoreceptors and that type of thing, as they’re flying in to find these flowers. So it is amazing to me. And if you look closely, you can see some of these flowers really show landing strips where that pollen and nectar are. Now, we know how these bees see, and they also see polarized light, which actually helps them when they’re flying. And this is from a study back in 2014 on how bees see color. And this is honeybees, but it’s the same for our bumblebees as well.
So if you look at these flowers — when I’m out hiking or I’m out working the garden, I always look at them and say, okay, what did this flower do to make sure that bees find it? What kind of adaptation did it create color-wise that I’m not seeing? So here, if we look at this crested iris, you know exactly where the pollen is. I can see those landing strips. I am sure for the bees it is an easy flight in. And over here, this blue-eyed grass, you can see these big kind of divots, these little folds in the flowers here — that is probably a landing strip as well. So it’s just a fun activity when you’re looking at flowers: how are the bees actually seeing these things?
Bumble Bee Cognition Studies
And we do know, the research lately of the last 10 years, bees are incredibly smart. And I’m going to talk a little bit about some of the studies that have been done. In 2016, there was a study done that went along with a study that was done later, in 2023, where bumblebees were actually taught how to move a flap to get to a sugar treat. They were taught how to pull a string to get to a sugar treat. But in 2024, just recently, bees moved a ball to solve the problem, and they were not taught to do it. So up here is a sugar source, and here is a ball, and the bee is put in there and knows the sugar source is there. So, I mean, that’s amazing to me. So as Rich said, we’re finding out that these bees of little brain actually have some abilities that are equivalent to what a primate sees. So why would bees need that skill? Well, they’re going to figure out flowers. They’re going to have to figure out where that nectar source is in those flowers. And as we mentioned, once they figure out one of that type of flower, they’re going to visit the same species over and over. So just amazing.
So all of those facts put together — the bee pile, their cognitive ability, what they see — everything was built to make them the perfect pollination machine.
Counting Bumble Bees for the Census
So, all right, what does that mean for us when we’ve got a pollinator census in two months? Well, you don’t have to know the species of the bumblebees for the pollinator census. You just need to know that we are dealing with bumblebees. And these — all of these pictures we’re taking during the census one of the years. So we have a two-spotted bumblebee here. We’ve got some American bumblebee — a lot of different types of bumblebees that I found. But for you, when you’re doing the census, all you need to know is, check, that is a bumblebee.
But I do want to show you some things that I think are really great. This is an American bumblebee, and one of the charts that Rich showed earlier shows us that this bee is considered vulnerable. It’s one that they’re really looking at as maybe being threatened. But one of the neat things that we have found since we’ve been doing the census is, we’re finding them more and more, at least in the Southeast, in some suburban areas like parks and urban areas or community gardens, which has been kind of surprising. Also, last year I found this Sandersoni bee when I was doing some bee work, which was a big excitement for me. They look like they just got out of bed, rumpled hair. So you’re going to see, as you’re out and about, looking at bumblebees more than the eastern bumblebee and learning more about what you see is fun.
Fuzzy Fanny vs. Shiny Hiney
But again, we don’t have to know that for the census. Hopefully you know by now that their body is covered with hair. They’re a fat bee with a small head. They have a large thorax and abdomen, and they have a hairy abdomen. We know that. And we also know, if we compare them to carpenter bees, carpenter bees have a smooth abdomen — which makes a lot of sense. If a carpenter bee is going to chew through wood to make a hole for a nest, and go in and out of that wooden hole, if she had a lot of hair all over her body, that’s going to create a lot of friction and a lot of problems for her as she maintains that nest. So having a bald abdomen is important. We call that a “shiny hiney,” right? We know that.
And here — this is a little bit of a blurry picture, but we have a smaller bumblebee here, but you see it’s a smaller head. I think of it kind of like a pickup truck. Whereas here, we have a carpenter bee, a bigger head, kind of more in line with the size of the thorax. And this is my friend Bodie Pennisi — he took this photo for us. All right, so I know you guys attended last week. I know that you attended the carpenter bee lecture, and I know that you know the difference between a carpenter bee and a bumblebee. So I know you all know it is a carpenter bee. You see that shiny hiney there. No yellow right up here. Yeah, definitely a beautiful carpenter bee.
Census Plants and Closing
When I worked with Rich and the team for the Southeast Bumblebee Atlas over the last several years, these are the plants that bumblebees were counted on. Now, this doesn’t necessarily mean that this is the plant that the bee is, because we don’t know — for example, whoever counted on a mountain mint counted the bees there. They don’t know what else is around. So, is that all that’s there? Are there other things to tempt the bees? But that being said, I think if you said, I’m starting from scratch and I want to build a pollinator garden for bumblebees, I think this is a pretty good list to get you started. This was from, I believe, 2024. And this is a chart on some of the bees that we saw during the observations for the Bumblebee Atlas. So you can see Bombus impatiens again, the two-spotted bumblebee. Some really exciting finds. So just a lot of fun out there searching for bumblebees. Okay.
So, in closing, I want you to realize that bumblebees are the superior pollinator. They need pollen and nectar for their life cycle. They have a lot of bee pile, or hair. They’re large and strong. They can shiver. And they buzz pollinate, like Rich showed us that video, and that’s important for crops like tomatoes and peppers where that pollen is really sticky. They have long tongues that help them get deep into the flower. Most of them are generalists, which means that they are not too picky about what they visit, but they will visit the same type of flower over and over. They can open the flower with their weight for that hidden pollen. And they have tarsal claws to really help them do a great job in navigating.
And to close, I just wanted to show you a bee from the UK. I was lucky enough to go to London, I guess a year and a half ago, to work with the Bumblebee Conservation Trust. And I fell in love with these bees with that white — bum, is what they say. So this is a bee in the heart of London, at one of their Kew Gardens, and you can see she’s grooming herself, but she has that really cute little white on her abdomen, which we just don’t see in the Southeast. So some people go to London for the food, some people go to see the London Eye. I wanted off that plane to see those bumblebees with the white on their abdomen.
All right. I know you all have those dates down. I know you are ready for August 21st and 22nd, just two months away. Hopefully this has given you some more information to really look at your bees a little bit differently. I’m going to stop sharing now, and we will take a few questions.
Closing Questions and Answers
Becky Griffin: I know Rich has been answering a few, and whatever else that we don’t answer here — because we are getting close to time — we will definitely send you answers, and we will post those with the recording and the resources that we have. All right. Okay, let’s see. Let’s find some Q&A. All right, Rich, I’m going to get you to unmute, and you can help me with some of these questions if you’re available to do so. One of them was, does diatomaceous earth harm bumblebees? And is there anything that can be done to remediate pesticides that are used by others nearby? Any thoughts on that?
Rich Hatfield: I believe that diatomaceous earth is not harmful. We’ll start with the easy one. Yeah. In terms of what to do about pesticides being used nearby — gosh, tough one. There’s a few things that you can do. I mean, it depends on how it’s being applied. If it’s being applied like sort of broadcast spray, or even airplane, that type of commercial-type spraying, or even with a tractor that’s being sprayed sort of off the back of it — one of the best things you could do is create like a hedgerow or a certain sort of physical barrier to prevent that. And then don’t put flowering plants in there. Just put, like, I don’t know — I’m out of my realm here with the Southeast, but something like bamboo or some kind of physical tall grass that’s going to provide a physical barrier to prevent the spray, but not attract a lot of insects, would be really the best thing that you could do. And then, if you’re going to plant any intentional habitat, you’re going to want to do it as far from that neighbor, or wherever, as possible.
And I did see some questions about, does spraying for mosquitoes impact bumblebees and other pollinators? And the short answer to that question is that it does, especially any program that’s spraying for adults. So if they’re using an adulticide, then it’s something that can impact bumblebees and other pollinators. And there’s some impact that can drift quite far on the properties. So we do want to be careful with mosquito spraying. And Xerces actually has a bunch of resources about controlling for mosquitoes, and using adulticides is obviously fairly ineffective. We need to be preventative and get rid of that standing water, and then use larvicides — that’s really the way to do it. So target the larval phase of the mosquito rather than the adult phase. Once they’re adults, it’s too late. You can’t really control them at that point. So anyway, I’m going on a little bit too far here, but there’s lots to talk about with pesticides.
Becky Griffin: Yeah. And while we answer a couple more questions, I’m going to go ahead and launch our end polls. And yeah. Okay. So I do see a lot of questions about flowers. And your local extension office is going to have a lot of resources on flowers that grow well in your region that don’t need a lot of inputs — because that’s another thing. We don’t want to plant things that need pesticide. We don’t want things that have powdery mildew growing for bees. We don’t want to have to treat for that. Xerces also, on their website, has a lot of resources, floral resource lists for the different areas of the country. So I will post links to those types of things.
And I also see a lot of questions about the pesticide issue. I think education and getting your neighbor to really love the bees — one of the things we have at our home is we have a restored prairie, and as people walk by, at first they think it’s junky. But then when I explain with a sign — you know, having signage, “this is for the bees” — then they want to stop and watch. And then, what can we do? So falling in love with bees really makes you want to watch your pesticide use, talk to your neighbors about what they’re using, or go and become a community advocate in your town hall. You know, that type of thing, I think, is also helpful.
Can you get a poster of all the bumblebees in the Southeast? Rich, do you know of — I know we’ve got some posters. Xerces has some posters. Pollinator.org has some posters. Bees of Your Backyard has some posters. I don’t know of anything that’s just for the Southeast, though. Do you?
Rich Hatfield: Not just for the Southeast, no. A few years ago, the Forest Service did produce a poster that was Eastern United States, which would include some species that are not found in the Southeast, but it would have all the 16 species that are in that region.
Becky Griffin: Yeah. Here’s a question for you, Rich. What happens to the queen bee in Florida, where they don’t really have a winter?
Rich Hatfield: Yeah, that’s a good question. There is some evidence that in more tropical regions, like certainly parts of Florida, there are year-round bumblebees. So they may have two broods in a year, or may actually just keep reproducing year-round. But most indications are that they still, for the most part, will overwinter. Even if it’s not true winter, they’ll still go into diapause for a period of time. But I think, with climate change and a whole bunch of other things going on, there’s probably all kinds of new adaptations coming on, and bumblebees will keep trying out new things and potentially adapting, and hopefully adapting to changing climates and making things happen. So yeah — but that’s, for the most part, I think they’re still going into some sort of diapause. But good question.
Becky Griffin: We’ll take one more question, because I want to make sure that we let everybody go on time. What range of habitat do bumblebees need? Let’s say you have a suburban yard and you really want to create full habitat. You want to make sure there’s places for nesting, you want to make sure there’s places for overwintering and a flower resource. How much space do they need?
Rich Hatfield: Good question. I think it’s probably pretty fair to say that, like, a diameter of around a half mile is probably about right, for like, if it was a really resource-rich area. That would probably suffice a colony. But you might get several overlapping colonies using that area too. And obviously, bumblebees are only a small fraction of the native bees in our region too, right? There’s, you know, even just there in the Southeast, there are hundreds of other species of bees that are using those habitats too. So it’s hard to know. And it’s really going to depend on how resource-rich, how many flowers there are, how many different flowering plants, different species there are. But, you know, bumblebees, generally speaking, are going to want to forage the shortest distance that they possibly can. Because it’s just — the economics work out better for them. They have to expend fewer calories to take in more calories. So they’re going to have as small of a habitat as they possibly can. And I could certainly imagine that around a half-mile diameter or so could do it, but it would have to be pretty resource-intensive.
Becky Griffin: One of the things I love about studying and working with bumblebees and bees in general is — Rich, when you and I were younger, we would hear about things like the bald eagle and how there weren’t going to be any, and there’s nothing we can do about it. But we know from our work that, yes, creating habitat in a small suburban yard really can make a difference. And you’ll see reproducing bees, and you’ll end up with a lot of American bumblebees, and that’s really a powerful thing. It makes you feel like you’re doing something positive for the environmental world.
All right, we are at 4:30. So I definitely want to thank Rich for coming on today and being my partner in this. It was a true honor to do this with you. I hope everyone enjoyed learning a little bit more about bumblebees. And Rich — Georgia Rich, Rich Braman — will have the recordings up hopefully by Friday. But if you don’t have it by Friday, don’t panic. He’s going to get it to you, and I will post the resources there. Next week, we’re going to be learning a little bit about butterflies, and we are excited about that. We’re going to have Dr. Sonia Altizer, who is the head of the entomology department at UGA. She does a lot of work with monarchs. She’s internationally known for that. And then Jeremy Rhoden, who actually works for the University of Florida as the census coordinator for that state. So that’s a good team to stay tuned for next week. So with that, we’ll let you go. I wish you all a great afternoon, and hopefully you’ll have some time to get outside and look for bumblebees.
Transcript processed for UGA Center for Urban Agriculture / GTBOP Archives — Great Southeast Pollinator Course
Source: Corrected SRT (Stage 1) — GTBOP_Transcript_2026-06-23_Bumblebees.srt (280 blocks)