“The biggest mistake a beginner can commit, is to try perfectioning (customising) hives, before having studied seriously apiculture. It’s not the hive that produces the honey, it’s the logical application of good methods, the hive is only a tool. Having not invented new hives, we (I) simply chose, amongst the best models, the one that seemed the easiest to operate and the most in harmony with the natural instincts of bees. This hive (Layens) had proved itself capable of such at the hand of many apiarists. In order to prove by the facts that our method was sound, it seemed useful to share the results during all those years. Beekeeping authors often forget to base their theories on facts (studies).”
George De Layens. (From l’élevage des abeilles par les procédés modernes, edition1893)
I spent about a half hour talking with Adam Novitt yesterday. About 5 years ago he did a very entertaining video about the Taranov Split – which would be an easy and effective way to move bees from your existing hives (Langstroth perhaps) into the Layen’s style Ez-Bees hive. It would also help you multiply hives in a way that mimics natural swarming. I’m hoping to do a Zoom interview with Adam for some Q&A. Here is the video –
This journey began long ago and the road has stretched out longer than we might have guessed. In the beginning, we were simply looking for a box into which we could put a swarm (if we were able to catch one).
The fun accelerated when we were able to figure out a box which might actually work, and put bees inside.
Next came the fun part, how to get more of these built, enough to test them in Spring of ’22. I thought I’d be good at this, but as simple as it seemed, no one came through and built parts as they’d promised (even when sent hundreds of dollars). I set off to get my boxes and use the local lumber company for parts.
To overcome the cutting errors, we dug up my skill-saw table and went to cutting plywood.
So at the moment we have boxes in 5 states with 3 in MN. Not where I’d like to be, but a good test.
We’ll keep you posted on how they shake out. Hopefully we will get at least a handful more when we get some frames built.
The EZ-Bees hosting box is the size wild bees like. But what do you do when the box is too small and the hive needs to grow. Here is a discussion from the facebook – Treatment-Free Layens Hives group. A wealth of knowledge.
“I feel like a teenager that won’t listen to his parents and has to make his own mistakes”
Thoughts on Taranov and walkaway splits by Andrew Gardner and Angella Tollerson
I wanted to increase my apiary by catching swarms only, per Keeping Bees With A Smile, which I still think is the best way. Unlike with many of YOU, though, here in the high desert plains of Colorado, swarms are very unreliable. (For 3 years I put out 5-10 bait hives and only caught one swarm in all that time!)
I decided last year that I needed to learn to split. I really liked the idea of the Taranov split since it so closely mimics natural swarming, and you may have seen me singing its praises in this group. But after doing it 3 times (and killing the queen while doing it the third time!), I’ve decided that it’s a complicated procedure during which a lot can go wrong, and it’s difficult to do with large, heavy Layens hives that can’t be disassembled like vertical hives.
I turned back to the de Layens book and noticed that his splitting procedure in paragraph 163 (diagram above) is the same concept as a Taranov split, with the improvement of using 2 hives to create the split instead of just 1. And, naturally, it’s much more adapted for use with his hive!
I’ve now decided that all along I should have just listened to the guy who invented my hive! If I don’t need a lot of new colonies, I’ll follow his splitting procedure in paragraph 163. If I lose a lot of colonies and need to make more splits, then I’ll follow his splitting procedure in paragraph 234 (which is basically a walk away split) since it only requires one colony for the split. And also hopefully supplement the splitting with a caught swarm once in a while! I’ll report back in a year or two on how it’s working!
Angela Tollerson I think I mentioned this earlier in PM but posting here for all to benefit: you can safely replicate the Taranov with much less stress by doing a shook swarm directly into a hive body. So instead of shaking frames onto a sheet you do it into a hive body with no live brood frames moved into the new hive. I personally would find the queen first and extract her safely with fingers or queen catcher and then gently release her into the shook swarm hive. Now, the question everyone is asking is why shake when you can do a walk away split with frames? Because to truly replicate the ecological benefit of a swarm you have to not vector mites in brood with the new split. The only mites you move are the phoretic ones on the nurse bees which they have 8 broodless days to hygienically groom from each other or might fall off the bees as in a swarm.
Andrew Gardner yes! I took that advice to heart and was amazed to see that that’s exactly what de Layens’ split method above is! He does mention moving one frame of brood, though, which I wouldn’t do. He doesn’t give the rationale, but I’m thinking it’s to give them a little honey and so that they can make a queen in case something happens to her in the process because he says, “one frame containing both brood of all ages and honey”.
Angela Tollerson Sounds like it was just to give them a head start since they don’t have the benefit of gorging honey to build up the way that a swarmed does. You could certainly move a few frames of honey over for them to help them get going. But I don’t think the brood is prudent if you’re trying to replicate a swarm.
Andrew Gardner I would definitely give them some frames of honey, but I agree…no brood! My thought also would be to do as I was doing with the Taranov splits: to smoke them a fair amount before the process in order to try to get them to gorge on honey a bit.
Mark Stoddard Jr. just curious what your plan is when you don’t want to expand your apiary anymore? Do you allow the bees to swarm and hope they find a safe home? I just did another split yesterday and two more of my hives swarmed while I was in the apiary! I’m at 9 hives with no more equipment and I will need to use swarm traps as temporary hives if making summer splits. When I get to 10 hives I have no urge to expand and would sell nucs but don’t know enough people in my area with Layens. Too many bees! What a problem to have 🙂
Andrew Gardner Indeed! What a problem to have! I’ve never had a hive swarm to my knowledge! I always have had bait hives around my apiary, and there’s basically no habitat for them around here, and I work from home, so I do think I probably would know if they had. But I’m also very prompt at adding frames when needed. But, yes, that was my plan…if all of my hives survive the winter and I don’t want more, my plan was to leave them alone and if they swarm to hopefully catch the swarm in one of my bait hives and give/sell them to someone else.
David Liedlich I do not have room to expand my apiary. I do a split every spring for several reasons. 1) To make up for winter loss. 2) As part of my mite management, the queenless hive goes through a broodless period. 3) I don’t have to buy bees. 4) I split a strong hive that came through winter and would swarm. I split them before they do that. If I time it right, I do it before there are queen cells. I prefer to move the old queen to the empty hive, to mimic swarming.
Mark Stoddard Jr. This is exactly what I do every spring too but I had 4 hives overwinter and now after splitting them and catching swarms I’m almost at my capacity. I typically do summer splits to avoid late swarms too but this year I’m stumped on wh…
Ross Millard I always thought walk away splits were very simple and pretty close to what happened naturally. Minus the part where they take a few frames with them.
Dan Irish Ok Andrew, my friend, let’s talk. First is it five or is it ten?? LOL I’m not being difficult but that’s a significant difference. I would encourage you to get ten up, every year. Maybe I’m misunderstanding,maybe you started with five and now are up to ten. If that’s the case, kudos. Next, remember swarms go in cycles just like all things. So maybe in the high plains of CO, the last three years have been the valley of your swarms cycle. When we were still in NC, I spoke with many of the local Beeks. They recount some years they would see, catch or hear about very few swarms. The last couple of years down there, some are catching 20 PLUS. My point is don’t get discouraged based on one in the last three years. The next aspect of your experience is location you’ve been hanging traps. Are you moving them around? I’m highly confident you know what to look for, maybe hang a couple in areas you initially thought……naw I’ll pass. I always like to note if a location didn’t attract a swarm one year, nothing goes back there, at least for a couple years. You may be on the verge of catching ten in one season. Splits. I’m not a big fan of splits for a number of bee perspective reasons. (sorry side note: I always wondered how the bees decide who’s leaving/staying when they swarm. Do they have a point system? Merit? Or do they just line up and count off by twos? 1’s stay 2’s leave??). I digress. When growing an apiary you really have to split. I know you’ve described it and are a fan but TBH I don’t know the Taranov split. I do walkaways. Call me a lazy Beek. Maybe I’m just getting old and have no desire to find the queen. Maybe I just like to do a split in ten minutes so as not to disrupt more than needed. Bottom line as you are increasing your apiary, indeed split survivor stock. Would be interested to hear how you killed the queen.
Andrew Gardner I had 9-10 bait hives out the last 2 years, about 5 the year before that, and 2 the year before that. And, yes, I moved them around. I am friends with the swarm coordinator for the local beekeeping association, and he did say that the number of swarms has been on a steady decline year to year. Lately, he mostly just gets calls for swarms from Lang beeks feeding lots of sugar to packages. LOL. But I’ll keep trying to catch swarms because I like getting that genetic diversity!
In 2021, Angelina genuinely embraced the cause of honeybee health. In the Vogue video, she reiterates the issues which we all know and then asks, “As I started working with Guerlaine, we spoke often about the bee… and then we really started to talk about what could we really do to improve the situation?”
Further, Natural Beekeeping advocates like Dr. Thomas Seeley, Cornell University and Dr. Leo Sharashkin point to the persistent survival of wild honeybees as proof that ‘modern’ commercial honey production (domestication) is harmful, dangerous and ultimately weakens our honeybees.
To answer Angelina’s question, by far the best thing (and it is such a simple thing) we can do, is restore habitat to the WILD honeybees. This provides both genetic and method diversity. For all time, honeybees have survived on their own. Only in modern times have they been threatened. Perhaps it says more about our ‘methods’ of domestication. The most dangerous threat to honeybees is human domestication and habitat destruction. What can we do? Re-Wild the bees by giving them small, well insulated houses. Let them move in on their own and multiply.
It’s a noble cause—trying to help bees thrive as populations face catastrophic collapse. One of the ways folks have been doing this recently is by purchasing bee houses. Bees will build their nests and lay their larvae inside these cute little tube-filled wood boxes, which have become prevalent at garden centers. Seemingly all you have to do is hang them on a tree and walk away.
Unfortunately for the bees, many commercially available bee houses don’t come with any instructions and are made out of the wrong materials. If they’re not well cared for they can end up being, basically, death traps.
Dirty and unnatural
As essential pollinators, bees help plants survive and propagate. But a variety of factors are stacking the cards against them. Climate change, pesticides, habitat loss, and disease are all conspiring to annihilate bees—including both commercial honeybees and various wild species—around the world. So it’s only natural to think that putting a house for them in your backyard would be a helpful step. Especially with companies marketing these houses as ways to help bees stay safe and attract them as pollinators for your garden.
“It’s such a fantastic desire to be helpful and fix the things we see that are broken around us,” Gwen Pearson an entomologist at Purdue University, told Earther. “That’s wonderful and I honor that so much, but the problem is the world is really complex.”
The most prevalent problem with bee houses is that when they’re not cared for properly, they can become breeding grounds for pests, mold, fungus, and disease. As Colin Purrington, an evolutionary biologist and bee house enthusiast who recently had a viral thread on Twitter about deadly bee houses, put it to Earther, it’s like having a hotel with no maid service. “If you were staying in a hotel and it never, ever cleaned anything it would be gross,” he said.
Pollen mites are one of the biggest threats to the habitability of bee houses located in humid environments or built of materials like bamboo that don’t dry easily. “If there’s no way for moisture to dissipate from the nest then the mites take over,” Purrington said.
When they hatch, these mites eat the pollen that bees leave for their young to feed on. Then, the mites latch on to the bees, hoping to get a ride to the nearest flower. Purrington, who runs a citizen science project on iNaturalist collecting images and information about the various parasites and diseases that can thrive in bee houses, said bees can become completely covered in mites to the point that they can’t even fly. “It’s a horrible sight,” he added.
Another problem with these houses is that, despite what conventional wisdom tells us, native bees in the U.S. are actually solitary. Honey bees—which usually live in large colonies—are actually invasive species that European settlers brought here to help with agriculture. Mason bees and other members of the American side of the apoidea family, while still essential pollinators, prefer a more lonely life, though they’re still attracted to bee houses.
“Bee houses do tend to aggregate certain bee species into close proximity with each other,” Eric Mader, co-director of the pollinator and agricultural biodiversity program at the Xerces Society for Invertebrate Conservation, told Earther in an email. Mader called out several genera, including Osmia, Megachile, Chelostoma and a few others in the family entomologists call “leaf cutting bees” because they cut small round pieces of leaves to wrap their around their larvae (much like swaddling) when they build their nests. He said that some of these species “have a natural tendency toward gregarious nesting, but in nature the lack of dense apartment-style housing units tends to keep members of those species spaced out a little further apart.”
Packing a bunch of species together into one box is not only ecologically weird, it can make them targets, Mader said. “The cheek-to-cheek occupancy of bee houses helps predators (woodpeckers for example), parasites (including wasps, mites, and others), and diseases find a dense host-bee population to exploit.”
A common setup of bee houses can cause other problems, too. Purrington noted that it’s bad for bees when a house is tied loosely to a tree or a post with a string rather than tightly secured in place. If the house is jolted hard enough, that it’s possible bee larvae could be knocked off their pollen ball food source, he said. And windy conditions can interfere with bees trying to get inside.
“The bees can’t land if it’s flapping around in the wind,” he said of mason bees. “They’re terrible at landing.”
A better bee house
This doesn’t mean that all bee houses are terrible and should be avoided at all costs. Finding bee houses made from proper, breathable materials (like easily removable paper straws, or natural woods that aren’t bamboo) can help alleviate some issues around mold and mite growth. More than anything, though, whether a bee house provides benefits depend on if owners are willing to put the time and effort into properly caring for the house and the bees that live there.
Regular bee care, Purrington said, involves storing the larvae-filled nests that the bees make inside the bee houses safely for the winter, cleaning and sanitizing the nests after the larvae have grown and left in the spring, and cycling out those breathable woods and paper straws regularly to make sure they’re not harboring parasites or bacteria. He also said it’s a good idea to cover the houses with metal netting to keep the birds out, as woodpeckers and bluejays find bee houses to be great restaurants.
Mader said that very small bee houses that don’t have too many rooms in them aren’t too bad. “Our general recommendation is to go small, not try to aggregate hundreds of bees in a small space, and to have fun with bee houses. If people want to try scaling up, they should educate themselves on the appropriate beekeeping systems for maintaining the health of their population.”
If you decide you want to put in the time and effort to keep a proper native bee house there are some good resources available. Pearson recommended The Bees in Your Backyard: A Guide to North America’s Beesto help you figure out if your native local bees even want to live in bee houses. The Xerces Society for Invertebrate Conservation, where Mader works, has extensive online resources for bee houses and bee keeping. And Mader recommended the free, downloadable book from the Sustainable Agriculture and Research group at the USDA Managing Alternative Pollinators.
Purrington recommended Crown Bees as a source for well-made bee houses and noted they have extensive educational blog posts and YouTube videos for keeping healthy bees. He has also compiled his own lists of bee houses that should be avoided and how to spot them, houses that are safe, and instructions on how to build your own bee house if you’re looking for a DIY project. All the experts also agreed that properly kept bee houses can be valuable tools for teaching kids about ecology and bee behavior.
But Pearson added that the best way to help bees and other pollinators in your yard is to forego the bee houses all together and, in fact, stop spending time and money on lawn care. “Right now what we have is we’ve legislated sterility in a lot of our neighborhoods,” she said.
Community regulations that you mow your lawn and keep it neat and tidy are an ecological nightmare for pollinators like bees, whose habitats rely on the mess nature makes when tree branches, leaves, and stems fall on the ground. The loss of that habitat has a huge impact on whether bees can survive and reproduce in our modern world.
“Just make an enormous mess in your yard and leave it there,” Pearson said. “Don’t trim stems for winter, leave bits of old wood around—all of that is great for bees to find a place to live. Don’t rake up the leaves, leave the dead spot in your yard… One of the things we can do that is super easy that will make a difference is just be lazy. Let things be messy. Let them be untidy.”
Given the holidays, this week has been a bit slower than the past few. I stopped at MidwestCedarHives and met with Jim there. Picked up a modified Layens frame, simplified for ease of production. Tuning the final prototype meant going to a slightly thicker plywood so that the frames wouldn’t drop in. Then we slightly modified the bottoms just a tiny bit – almost imperceptibly – but just enough to keep the bee space consistent. From there we went to the hive assembly.
I did a very precise cut layout but I cut them free hand with my circle saw. It was worse than that because I really don’t have a workshop. I put the 4×8′ sheet on top of my lawn tractor. The snowblower spout kinda made it level but very tippy. I should have set up a tripod to document the craziness. Plus it was only 15F which is really cold to do woodworking. Those down-south beekeepers. The prototype really did come out perfectly. Now the assembly shop will work on replicating that with CNC cutting and see if theirs is as good. I suggested that they NOT take my measurements for granted but do them over.
The plan right now is to produce 100 to prove the concept. Three research universities have expressed interest, lots of friends. Late this past week, I created an Indiegogo account. They are the people who helped get the FlowHive launched. Of course the difference is that this Bee House really is designed for people who merely want to house and have bees, whether the bees stay or go, produce honey or not, these boxes will create wonderful habitat for bees to move in, live, swarm and perhaps even produce surplus honey.
So much is happening it is hard to keep it all straight. Rather than posts on multiple social groups, better to lay it out here. To make it into smaller bites, I’ll be writing weekly updates. If you share your email, we’ll figure out a way to send you updates – like a newsletter. Hopefully you will join us in this adventure.
Welcome friends from the Treatment-Free Beekeepers facebook group. Special thanks to Michael Cox, co-founder for an encouraging conversation. He felt the idea of wildspread beehouses to give wild bees places to live (and the idea of a wide ranging study) were a great way for average people to get involved. Also welcome to the Layens Hive Treatment-Free Beekeeping facebook group. Great to have you join in.
Last week I heard back from Dr. Thomas D. Seeley, Cornell University. He has been very encouraging, perhaps in part because, in an interesting coincidence, the Ez-Bees beehouse happens to almost exactly match the insulation, volume and rough interior of wild bee tree hives.
You may have seen the Bee Audacious conference. Had a wonderful chat with Bonnie Morse who organized it. She connected me with Dr. Michael Smith at Auburn. Also had a long conversation with Dr. Marla Spivak, U of Minn. We’re working on a way for average people to put up beehouses, let us know if bees move in, update survival through next year and see if they can harvest some surplus honey. I’m working with Gene Rene’, a professional photographer who hosts a popular video channel and already has a beekeeping course on adapting it to help non-beekeepers know what to do with the beehouses.
Many of my web visitors are soon-to-be beekeepers preparing for their first delivery of honey bees. They have read, attended classes, and talked to other beekeepers. Some write to me with a few last-minute questions. But what they envision and what I foresee are completely different.
I was reminded of this beekeeping reality while watching a beginner video on YouTube. While sappy music played in the background, a lilting voice explained that once you become a beekeeper you will embrace nature for the first time! You will become attuned to weather and blooms! You will blossom as a person!
Wow. I imagine a barefoot flower child romping through a verdant meadow, a ring of daisies in her hair and a bouquet of dandelions clutched in her fist. Beekeeping is your entry into a world of peace and love and grass stains. Kumbaya in a box.
Selling an image
Beekeepers who are frantically pushing their books or e-courses spout all this nonsense with a straight face. Ah! The wonders of becoming one with the insects. None of them explain that beekeeping degrades your personal standards. Your table manners erode. Your language goes to hell. Your housekeeping falters. And your tolerance for sticky and gooey takes a turn for the worse. You become unforgivably messy, and your definition of what is “gross” defies social norms.
Family values take on new meaning
Once you get your bees, that pulsating mound of venom becomes the most important member of your family. The side yard where the kids used to play is off limits. The cat can no longer lounge in her favorite sun spot. The dog’s water bowl is full of insects. Blooming weeds are sacrosanct, and your partner can no longer mow in the middle of the day. Life as your family used to know it evaporates because, as everyone knows, you mustn’t bother the bees.
It doesn’t take long before everything in your home is gooey. Before you began your beekeeping adventure, you believed that honey was sticky. But honey, easily neutralized with water, doesn’t hold a candle to propolis, beeswax, and pollen. You have no idea. I gleefully await your first encounter with a glistening wad of propolis on a hot day. Tee hee.
One day last year, while carrying a sack of groceries and finding himself unable to release his hand from the front door, my husband reached his limit. After giving me the look, he drenched a rag in alcohol and said, “This morning I got stuck on the barn door. And if you haven’t noticed, your tailgate is attracting flies.” Oops.
Within a few days, he replaced every door knob on the property with a lever handle. The new rule: When coming inside, I am never to touch the levers. Instead, I must open them with my elbows which, for the most part, are free from bee “stuff.”
Your language will deteriorate
I’ve heard it called “bee language.” Bee language is an apt description because it is universally understood by all beekeepers. It consists of short, staccato words, strung together randomly, using only one punctuation mark! Delivered in loud outbursts or softly under one’s breath, these words are concise evaluations of your present circumstance. In English, they usually run four-letters in length, and often begin with consonants such as f, s, or d.
Your personal appearance will regress
Once upon a time, I was vainly particular about my appearance. A spot on my outfit was humiliating beyond words. Imagine wearing your food on your shirt! But recently, before a quick trip to Home Depot, I examined my clothes in a mirror. Well, the propolis stain across my stomach wasn’t that bad. In fact, it was barely noticeable if I held my arm in front of it. For a brief moment, I considered tying my left arm in a sling.
As a teenager, a zit on my face would have sent me into hiding. But now I examine the red welt on my chin and decide it looks like a mosquito bite. No big deal. After closer inspection, I scrape the stinger from the center. There! Good as new. Nowadays, as long as my eyes aren’t swollen shut, I’m good to go.
Messiness knows no bounds
If you plan to lead a neat and orderly life, you have no business being a beekeeper. Personally, I no longer have the space to be neat.
Today, as I glance around my once pristine kitchen, I see piles of honeycombs, some in frames and some not. There are honeycombs stacked on my dining room table, and piled in, on, and beneath the cupboards. They take up the space next to the refrigerator and the mixer. They completely cover the cutting board and fill the broiler pan. Others are stacked in my office and garage.
My shed, once neat and organized, is filled with bags of beeswax, buckets of old candy board, canisters of propolis, and stacks of end bars, nails, and assorted hive tools. The floor and windowsills are littered with dead bees and frame scrapings. Each time I decide to clean it up, I can’t figure out where to start, so I don’t. This is not the me I grew up with.
A purpose for pocketses
Worse, I have things in my pockets, things no normal woman carries in pockets. A queen cell. A dead bumble bee. A crushed flower to identify. Some kind of thing that was crawling on my top bars. A screw driver. A test tube. A few seeds.
Even when I try to do things right, I often fail. One day, I swept through the garage with my bee suit and said, “Hey Rich, I’m going to wash this. Do you have anything else for the load?” He looked as if I lost my mind. “With that? Are you kidding?” This hurt my feelings. Apparently, he believes his filthy, oily car rags are no match for my bee suit.
About the freezer
The freezer, which used to hold food, has also become a point of contention. My freezer now contains honey, swarm lures, mite meds of various styles, pollen pellets, queen pheromones, and pollen patties. It also contains test tubes full of native bees and wasps, vials (viles) of parasites, and samples of frass. But the real backlash occurred when I began freezing frames of drone larvae. Apparently, when someone is looking for dinner, rafts of frozen, mite-infested drone larvae don’t spark the appetite. Who knew?
Your purchasing habits change
As a beekeeper, you buy strange things. A truckload of sugar is questionable. A case of isopropyl alcohol is odd. A case of EverClear is downright weird. I used to feel compelled to explain my purchases to people who stared. Now I want to say, “If you don’t like it, don’t look!” No wonder Amazon is my friend. I now buy everything in plain brown boxes.
Lastly, you have neighbors. They used to be your friends, but now you hide when you see them. You live in fear they will complain about your bees stinging, chasing their grandchildren, pooping on their laundry, or drinking from their pool. If cornered, you pretend you haven’t a clue what they’re talking about.
But rather than being cornered, you cross the street to avoid passing, change grocery stores, and move your bank account. You put in automatic sprinklers so you don’t have to stand outside with a hose in hand, you walk your dog at night, and you park your car in the garage. You wonder what happened to you, why you’ve become so antisocial, but the answer is simple. You became a beekeeper.
Should you skip it?
Am I trying to convince you to avoid beekeeping? Not a chance. I’m just saying that beekeeping isn’t all sweetness and light. It’s so much more fun than that! And it may be the most remarkable life-changing experience in your entire existence—whether for better or for worse.
Microbes in flowers are crucial to bee diets, and microbiome changes could be starving the insects
Ask an entomologist what makes a bee a bee, and you’ll likely get some version of “bees are just wasps that went vegetarian.” New research shows that isn’t true. Bees are actually omnivores, and their meat is microbes. This finding may open a new window on why bees are in trouble: Anything that disrupts the microbial community in a bee’s food, whether it is high heat linked to climate change, fungicides or another stressor, could be causing developing bees to starve.
Bees are supreme pollinators because of what their babies eat. Most animals visit flowers to pilfer nectar, and they may or may not brush up against pollen and carry it to the next flower. Female bees, conversely, deliberately collect pollen, along with nectar, to feed their babes. This larval food choice is part of what defines a bee.
Scientists have known for decades that fermenting microbes are present in pollen, but no one had seemed to consider whether they were also an important food for bees. The microbes function as an “external rumen” that breaks down parts of the pollen. It stands to reason that bees might ingest some microbes, but two researchers decided to investigate whether they eat enough to make them omnivores—and if the bees truly need those microbes to thrive.
Prarthana Dharampal of the University of Wisconsin–Madison and Shawn Steffan, who works jointly at the university and the U. S. Department of Agriculture’s Agricultural Research Service (ARS), assessed 14 different bee species in six of the seven bee families. They found that bees eat substantial amounts of microbes, enough to change how they fit within food webs. Scientists use a scale to categorize where organisms belong in that web: those that make their own food, such as plants, register at so-called trophic position 1 (TP 1), herbivores register at TP 2 and carnivores do so at TP 3, or even higher if they eat other carnivores. The average TP across all the bees studied was 2.6, putting them squarely in the omnivore spot, halfway between herbivores and carnivores. Interestingly, the trophic position varied among families, ranging from just a bit above herbivores (2.11) to solid carnivores (3.09). Now that the TP is known, Dharampal says she wonders whether bees are really foraging for the pollen, or are foraging for the microbes that are associated with the pollen.Advertisement
For most people, the idea that microorganisms can qualify as meat is radical.In the past four years, Steffan and his colleagues, including Dharampal, have published a series of papers laying out their evidence that microbes are an important part of a variety of food webs, including those that involve bees. Their findings confirm that fungi, bacteria and other microscopic players can fit anywhere in the food web, upending our vision of predator and prey, carnivore and herbivore—and what makes a bee a bee.
Steffan and his colleagues have also shown that microbial meat is a necessary part of bees’ diet. The researchers tested a species of mason bee that lays eggs in aboveground tubes that are easy to access and transport. In each tube, the mason bee lays a series of eggs, each on its own wad of pollen and nectar. The researchers had a Utah beekeeper send them a batch of tubes immediately after the bees filled them. They then took the eggs off the wads and separated males from females and used only the male bee larvae, divided into seven groups of 12. The scientists sterilized half of the pollen and then fed different mixes of sterilized and unsterilized pollen to the groups. As the percentage of sterilized pollen in the food increased, so did the larvae’s likelihood of dying. The larvae also weighed less and took longer to mature. “Microbes are a very important source of nutrients for these bees,” Dharampal says. “If you take away this critical source, or portion, of their diet, they suffer tremendously.”
The idea that bees are vegetarian is entrenched in entomology, and Steffan admits he and his colleagues ran into headwinds when trying to get their papers related to omnivory in bees accepted. Ultimately, they were published in the American Naturalist and Proceedings of the Royal Society B, respectively. Gloria Degrandi-Hoffman, who works for ARS and has investigated the honey bee microbiome but was not part of the work, says that the scientific community is always skeptical. When a new finding goes against a widely held perception, people take some convincing.
The mason bee results suggest that bees could suffer or starve if certain microbes disappear from their diet. Scientists have attributed the declines of both managed and wild bees to various combinations of habitat loss and degradation, pests and pathogens, pesticide exposure and climate change. They have largely focused on how such factors impact bees directly. The next step is to look at whether the stressors may affect the pollen-borne microbes. Steffan says any stressor that throws the external rumen out of whack could be “an indirect, but no less lethal” way of killing bees.
One such factor is heat from climate change. “It may not be that heat is directly lethal for bee development,” Steffan says. “But it very well could be that high heat knocks out the microbial symbionts in the pollen, and then the bee suffers from the lack of microbes.” Steffan and Dharampal are currently investigating this possibility.Advertisement
Fungicides could be culprits, too. Although more research needs to be done, Steffan says, “we have ample evidence, at this point, that fungicides dramatically alter the microbial community of fermenting pollen.” And, he adds, “agriculturaluse of fungicides is very likely a primary stressor—the primary stressor—for bee decline.”
Of course, failing bee populations can cripple the crops and wild plants they help to pollinate. Around three fourths of the earth’s flowering plants and cropsbenefit from animal pollinators, including 87 of the 115 leading global food crops. The 20,000 species of bees in the world are not the only animals that pollinate, but they are top pollinators for many staples.
Knowing the role of pollen microbes may eventually help solve conservation challenges by, for example, directing flower choices for habitat restoration. Sandra Rehan of York University in Toronto, who studies microbial life associated with wild bees and was not part of the recent papers, says the findings “will have long-term conservation applications once we do associate the flowers, the landscape and the microbes.” In a 2017 study, she and her co-authors wrote, “Pollinator habitat restoration efforts may need to consider flower plantings that increase the presence of core bacteria that are found in flowers, adults, and pollen provisions, such as Lactobacillus and Saccharibacter.Future work is needed to determine the role of these core bacteria in restoration of healthy pollinator communities.”
The new insight about pollen microbes is just the latest example of how important the microbiome is in all realms of life, which we may have ignored to our peril. “We, as animals and flowering plants have flourished, to the extent that we are able to cooperate, co-opt and commandeer microbial services,” Steffan says. He adds that we view food webs through the lens of vertebrates and mammals, but microbes have been on the planet much longer than animals or plants. Steffan, Dharampal and others call for a radical revision of how we view life on earth. At the end of their American Naturalist paper, they write, “Considering bee-microbe symbioses from the microbial perspective, microbes can be viewed as avid beekeepers, facilitating and assisting their faunal symbionts in the annual pollen harvest.”