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Oct. 24, 2022

Winter Bees, Summer Bees and Imidacloprid (S5, E19)

Winter Bees, Summer Bees and Imidacloprid (S5, E19)

Winter bees, those bees that emerge during the cold winter months when there is little to no exposure to the world outside, are very different from summer bees, which emerge during the hectic and exposed to everything bees are exposed to in their...

Winter bees, those bees that emerge during the cold winter months when there is little to no exposure to the world outside, are very different from summer bees, which emerge during the hectic and exposed to everything bees are exposed to in their environment. In today’s episode, we talk with Drs. Mohamed Alburaki and Miguel Corona, two USDA-ARS entomologists researching these differences and specifically the effects of the neonaticide imidacloprid on developing bee larvae.

The environment for winter bees is almost exclusively limited to what happens inside the hive. They live months longer than summer bees. Summer bees, on the other hand, live very short lives. Summer bees are either nurse bees or foragers, or maybe both, so they are exposed to all the things their environment has to offer. One of those is exposure to pesticides, the most common is imidacloprid.

It turns out, summer bees tend to prefer food given to them that has some small amount of this pesticide in it.  The speculation is that the taste is what they are used to – all summer long they ate food tainted with this pesticide. Meanwhile, winter bees, who never foraged or fed bees with nectar or pollen exposed to this pesticide, didn’t like it at all and would avoid it at all costs.

What this means for beekeepers is that managing your bees to avoid pesticides is the best option you can have. If you can’t avoid it, be aware of your bee’s tendency to favor the pesticide taste, if that is what they were raised on. It’s a complicated and toxic world out there. Be aware. You can read this very well thought out USDA paper by clicking on the link provided. You may have to read it twice. We had to read it more than that, but it was well worth the time.

We hope you enjoy the episode. Leave comments and questions in the Comments Section of the episode's website.

Thank you for listening!

Links and websites mentioned in this podcast: 

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S5, E19 – Winter Bees, Summer Bees and Imidacloprid


Jeff Ott: Welcome to Beekeeping Today Podcast presented by Bee Culture. Beekeeping Today podcast is your source for beekeeping news, information, and entertainment. I'm Jeff Ott.

Kim Flottum: I'm Kim Flottum.

Global Patties: Hey, Jeff and Kim. Today's sponsor is Global Patties. They're a family-operated business that manufactures protein supplement patties for honeybees. It's a good time to think about honeybee nutrition. Feeding your hives protein supplement patties will ensure that they produce strong and healthy colonies by increasing root production and overall honey flow. Now is a great time to consider what type of patty is right for your area and your honeybees. Global offers a variety of standard patties as well as custom patties to meet your needs.

No matter where you are Global is ready to serve you out of their manufacturing plants in Airdrie, Alberta, and in Butte, Montana, or from distribution depots across the continent. Visit them today at

Jeff: Thanks, Sherry, and thank you, Global Patties. Each week we get to talk about how much we appreciate our sponsor's support, and we know you'd rather we get right to talk about beekeeping. However, our great sponsors are critical to help making all of this happen. From the transcripts, the hosting fees, the software, the hardware, the microphones, the subscriptions, the recorders. They enable each episode. With that, thanks to Bee Culture Magazine for continuing their presenting sponsorship of this podcast. Bee Culture has been the magazine for American Beekeeping since 1873. Subscribe to Bee Culture Today.

Hey, everybody, thanks for joining us. We're really happy you're here. Before we get started, just a quick reminder to subscribe or follow Beekeeping Today Podcast and give us a five-star rating. It really does help. Also, we are now adding complete transcripts of each episode on the website after the show notes. Check them out. You can also leave questions and comments online under each show. You can leave a comment, ask a question, reply to a question, ours or our listeners. Click on leave a comment at the top of the episode's show notes to join the discussion.

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Hey, everybody, thanks again for joining us. Today we have two USDA ARS researchers to talk about their recently published paper on the differences between winter bees and summer bees preferences to food painted by the pesticide imidacloprid. We also briefly discussed their paper comparing the efficiency of the standard wooden Langstroth hive to newer polyurethane hives. Both of these papers are topical for today's beekeepers. Now that fall is here, honey is harvested, and most of us are buttoning up our colonies for the winter.

What is a beekeeper to do with all that newfound time? There are lots you can do. Get caught up in all your reading. Gather up your beekeeping magazines and journals. Maybe that book you impulsively bought and haven't opened. Maybe you are a woodworker and you can set up for making next year's equipment. Of course, if you're like me, you could finally get after all of those household repairs and chores you put off during the summer. I suggest you consider one more activity. Check out your local bee club. Maybe even join it. If you are already a member of a club, attend a meeting or two. A local beekeeping organization is a wonderful resource for beekeepers, regardless of your experience.

How is this so? If you're a new beekeeper, you will meet other new beekeepers who have the exact same questions you have on what you saw and experienced this past season. They are facing winter with the same concerns. At the meeting, you'll be able to ask your questions and receive an answer or two from more experienced beekeepers. This is important from experienced beekeepers in your local area. If you haven't heard it before, all beekeeping is local. As you read that book or watch that YouTube video and listen to that beekeeper, look at their surroundings.

Do they live where you do? Are they located in the Midwest and you're located in the Northeast? Are they in Florida and you in Oregon? Yes, you are both keeping bees in boxes, but the environment is different, the timing is different, and the small variances in management need to make a big difference on whether or not your bee survived the change of seasons or are strong enough to produce a surplus honey crop. I believe that a local beekeeper who has kept their bees through multiple seasons is a more valuable resource to you as a beekeeper than any book or YouTube video.

If you're an experienced beekeeper who hasn't joined a club or join one but doesn't attend meetings, break out of your stasis and give back to other beekeepers. If you've been keeping bees for years and years and have a wealth of experience that can help newer beekeepers, do so, share it. I know not every bee club works for every beekeeper. Check to see if there's another bee club nearby. Or you may consider joining the state beekeeping organization. There's a bee club that will be a good fit for you. Oh, and one last benefit of a bee club.

When it comes time to move that bee yard, you will know who you can call to help. Just be ready to lend a hand when they call you. Okay, let's get on with our talk with doctors Mohamed Alburaki and Miguel Corona about their research on the effects of the neonic imidacloprid on winter versus summer bees. First, a quick word from our friends at Strong Microbials.


StrongMicrobials: Hey, beekeepers. Many times during the year, honeybees encounter scarcity of floral sources. As good beekeepers, we feed our bees artificial diets of protein and carbohydrates to keep them going during those stressful times. What is missing, though, are key components. The good microbes necessary for a bee to digest the food and convert it into metabolic energy.

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Jeff: While you're at the strong microbial site, make sure you click on and subscribe to The Hive, the regular newsletter full of interesting beekeeping facts and product updates. Hey everybody, welcome back. Sitting across the virtual zoom table right now are two of the USDA ARS honeybee bee researchers from Beltsville, Maryland. We have with us Dr. Mohamed Alburaki and Dr. Miguel Corona. They both have just completed a couple of papers that we found really interesting and wanted to bring it to your attention. The first one was the effects of the imidacloprid on the seasonal phenotypes of honeybees.

Just how does that affect honeybees in the summer and in the winter? The second paper that we'd like to talk about is the polyurethane hives versus the wooden hives and insulation through the winter. After that brief introduction to very important papers, welcome to Bee Keeping Today Podcast.

Miguel Corona: Thank you. Thank you for the invitation.

Kim: I spent a fair amount of time studying the paper that you did and what you call winter bees and summer bees and you found some significant differences. Basically, can one or both of you sort out the difference between what you are calling a summer bee and a winter bee because I think beekeepers have a feel for summer bees and winter bees, but I want to make sure that they understand what you were using as a definition for these two.

Mohamed Alburaki: Hi, everyone, thank you very much for having us and it's really nice to be with you and the audience too and beekeepers to really facilitate and simplify what we are doing in terms of research because research usually tend to be complicated and us beekeepers we say, okay, those are big papers, big work, but what is in it for us in terms of day-to-day beekeepers? Basically, as beekeepers, we know that we've got summer bees and winter bees. That's not new. Those are two different seasonal of phenotype of bees. We don't know-- Usually what we tend to do is we tend to experiment on the summer bees.

When the season is spring, summer, we go we bring bees from the field because they are out there. You see them day to day, they forage, they come here, there. We rarely conduct experiments on winter bees. That case, because winter bees are clustering, they're in the hive, and we tend to really ignore them a little bit more than summer bees. All our focus is really on the summer bees, and within the summer bees, we know that we've got what we call the nurses and the foragers.

This is also like a different classification in terms of tasks, what they do in terms of tasks. Are they all the same? Yes, they are all bees eventually, but summer bees are different than winter bees because of many different physiological aspects as well as. other stuff that we can talk about later on, but also foragers are different than nurses. They are different in the task they do and they're different in the longevity, how much they can survive. This is also different from one species to another. You've got variation and when we study any effect on bees we tend to generalize, oh, this stuff is killing our bees, but it's killing what? What is more susceptible to this stressor that we're studying? Could the winter bees be more susceptible or the summer bees or the foragers or the nurses? Here we've shed more light on this type of aspect vis-a-vis imidacloprid. As we know, imidacloprid is highly toxic neonicotinoid used widely on cropping and many other trees and arches. That was basically how we approach that question and this experiment.

Kim: What you're telling me is that winter bees are bees that are born when bees aren't foraging? I mightn't even say winter, just when bees aren't foraging so their experiences and exposures are going to be different than bees that are born in the summer and are either nurses and are being exposed to outside influences when foragers come back or they're born as foragers and they're directly influenced. You've got winter bees who are basically virgins in a whole lot of ways and summer bees that are exposed to the real world pretty much. Am I close?

Mohamed: Yes. The nature of their job is different which will give them different probability of exposure to stressors. That is to summarize. Yes, you are right, Kim.

Kim: You also use another term in the paper and you call it naive bees and these are bees that once they emerge from their cell as adults they don't have an opportunity to interact with other adult bees in the hives. Is that correct?

Miguel: The bees, when they born in the colony, they are exposed to other adult bees. One important thing that we start to understanding is that transfer of bacteria or the microbiota, this in the last year has been very important. Almost every aspect that we know about honeybee biology is affected by the microbiota including this ethical pesticide. This is why we have the idea to test this effect.

Then most of the studies probably done were conducted using bees with naive because they emerged in the lab, they are not exposed to other adult bees and they lack the microbiota. They have out righted microbiota. Now we know these bees actually are more sensitive to many stressors. One of the contribution of the work that we did was just to show that how the microbiota is affecting the resistant to pesticide and turned now that microbiota actually held a lot the bees to resist these stressors.

Jeff: You call it the microbiotics. Is there any a predominant microbiota?

Miguel: Yes, these bacteria have been a study and there is several general bacteria for example lactobacillus that are predominant and very much like a human. It's very much the same thing

Mohamed: The term you've inquired about like naive, I added it by purpose. In fact, it's used in our field, but here it gives you the idea of those bees are so naive that they don't know what they're doing. They just emerged. They are unexperienced. Basically, it's really to say they are unexperienced. Why they are unexperienced because of their age, so they are very young, a couple day old and that's the first thing. The second thing, they have not been exposed to older mates in the hive, which is to say, okay, they came to the workforce and they've never taken any training or any webinar to know what they are supposed to do. That is the exact meaning of naive in that context.

Kim: The behaviors that they exhibit once they've emerged are going to be not influenced by any diet they've received from other worker bees. Any experiences they've had either with the other bees in or out of the hive or, actually, they're just walking around trying to figure out what to do without any help.

Mohamed: Correct. That is what we did in term of one of the category that we've tested is those bees that we called in the paper bees emerged in the lab. I guess that was the term used. The category of bees emerged in the lab are those naive bees. They've never been in the colony or in the hive. They've never been taught by older mates. "Okay, yes, what are you doing over there? Come here, clean here, do this, learn about this." They've never been in communication with more experienced bees, so how they would behave if we give them a choice.

That was one idea and then how bees emerged inside of the hive with which were exposed to older mates, how they would behave under the same circumstances and the third category was winter bees. Winter bees are very experienced bees because they are much older, they have a much more developed microbiota compared to the other two categories. Then we run the experiment and then we were looking, seeing how what choice they would make every one of these categories and how the pesticides would alter their behavior as well as their toxicity or mortality or how also they would exhibit preference to a specific diet offered because this experiment was a dual choice, so we offered them two choice and then we observe which one they would prefer and which one is killing them more and which one is affecting them more.

Kim: All of the bees that were in this and there were, I want to say, I think the number was 2,700 bees and 27 different cages you gave each of these cages two choices of diet. The bees were free to choose whichever one they want and what you were looking at is the difference between these three categories of bees on the choices that they made. Am I close?

Mohamed: Correct.

Kim: What were you feeding them?

Mohamed: Basically the feeding, we've got different type of feed. The feeding usually it's called ad libitum. Ad libitum is when you offer them something and they are free to pick and eat as much as they want their content. Other type of experiment you can subject them usually when it's toxicity experiment you subject them to a specific dose. You give them like 200 microliters of this dose and that's it. You starve them, you give them 200 microliters and then you keep them with this 200 or 20 microliter. 200 is too much in fact. 20 microliter and then you observe to see the toxicity and how much it's effect. That's not the case in our case. In our case, we give them sugar syrup control, one choice, clean one like the one we give when we feed them in the wintertime. One to one sacarose, sugar syrup, one kilogram to one-liter water, and then the other one was the same sacarose, the same sugar syrup, but it was tinted with two different concentration of imidacloprid, 5 ppb, and 20 ppb.

Kim: My choice is then if I'm one of these bees I can have pure sugar syrup. I can choose sugar syrup with five parts per billion imidacloprid or I can choose sugar syrup with 20 parts per billion imidacloprid. What you were looking at were basically, as I understand it, trying to measure which choice each of these different kinds of bees made on a fairly routine basis.

Mohamed: Yes, but they didn't have a choice between the 5 and 20 in fact. What they had a choice, one category was they had a choice between 5 ppb and a clean syrup control, and another cage had a choice between 20 ppb and a control. Then a third cage had a choice between two same controls, you see? They are the same one to be able to compare

Kim: In a real-world situation, which of these two treatments, the 5 or the 20 parts per billion imidacloprid would be somewhat realistic in terms of a bee foraging on a flower that had been sprayed? Do you have a feel for that?

Mohamed: Yes. In fact, those the 5, 20, and the 100 usually we use a lot this three different concentration. Now I need to clarify first that the LD-50, the half-lethal dose of imidacloprid breed for honey bees is 13 ppb. Basically, the five is sub-lethal concentration if you want. The 20 is a lethal concentration because it's more than those 13 ppb of LD-50 for bees. Basically, what we've used is we've used a sub-lethal concentration which is it should not kill them badly. [laughs] Let's put it that way. Then at 20, which should be lethal. They should die if they drink properly and they accumulate a lethal dose. Usually also in other experiments, we've used the highly lethal dose over lethal dose, which is the 100 ppb, okay. That is the distribution of the concentration we've used in that experiment.

Kim: I've got a feel for what kind of bees we're talking about and what you're offering them to make choices with that bees that have no experience, bees that had lots of experience, and which one did they choose? The naive bees that had no experience with other bees at all compared to the bees that were very old and had been around a long time. Was there a big difference, some difference, no difference?

Mohamed: In fact, we've seen a huge difference in their behavior as well as in their preference and how they stick to their preference, as well as the effects of the pesticide on their survival. That's the measure finding of this work is that the three different categories, Kim, that you've just mentioned, in fact, they showed complete difference in their preference. Why this is important because in the summertime we want to make sure that when our bees are exposed to neonics outside of the hive, which one will die first?

Are the young bees, the naive bees, let's call them, are going to die first or the one foraging in the field a little bit older, couple weeks old?

When they bring this pesticide and chemicals within the pollen or within contaminated with their nectar or on their bodies and they store it inside of the colony, they're going to eat it in the wintertime. If the concentration of pesticide is accumulating in the wintertime and bees are feeding on this stored food, then the winter bees will be susceptible to collapse due to chronic toxicity throughout time.

This is basically what we are testing here, because if the winter bees, for example, are rejecting the tinted, or let's say the food that is contaminated with imidacloprid then they will have higher chance of survival because they will not like it, they will not consume it. They will feel that it is tinted or it is contaminated with this toxic molecule. You know what? I'm not going to eat it. I'm going to eat from a different cell, whether it's pollen or whether it's honey. That is the idea here, or they would say, you know what? I like it, it smell like, I don't know, like menthol or strawberries, or I like this flavor, and they start eating from that flavor.

Then they accumulate huge amounts. They prefer it over the clean syrup, the clean pollen, or the clean nectar and then they get toxicities because of this high consumption and because of the preference they've shown, and they've picked because they like it, they desire that flavor. Yes, this is the major thing that will have ramification. In fact, their preference will have ramification on their survival and toxicity.

Jeff: There's a lot to unpack in what Mohamed just said. Let's take that opportunity to hear from one of our sponsors.

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Kim: Let me ask you this, you have some bees out there that have not been exposed to any other bees in their very short lifetime, and as a result, they really have no level of microbiota in their gut, in their intestines, did you find that bees that had an ample supply of microbiota compared to those that had none, was there a difference in survival even between the two treatments, let alone the two different kinds of bees?

Mohamed: What we found to make it very simple, flat, like straight to the point, is that we can't say bees without microbiota. That's almost impossible. You always have a slight level of microbiota inoculation when the bees are emerging. They will improve the level of their microbiota gradually by trophallaxis with other bees and by eating pollen, by eating nectar, so they will boost the level of the microbiota. In our case here, the summer bees emerged in lab with weak-- we suspect that they have a weak microbiota, very undeveloped microbiota.

Guess what they do? In fact, what they did is they've been avoiding the imidacloprid all the way along like from 5ppb to 20 in both choice. We give them the choice they were running like crazy to just the syrup, the clean syrup. They will avoiding the imidacloprid. For why they were doing that? Even when we challenged them with a rotation.

The rotation is very important because at the middle of the experiment, after nine days, if I remember well what we did is we've switched the position of the two syringes to trick them to see if they are really just attached to the local physical location of the syrup or they really like the taste of it. You need to uncouple these two factors. What they did is they don't care about the location of the syrup, they want the taste of it because they were changing side and going back like following the source they liked. In the case of these emerged in the lab without microbiota what they were doing-- in fact, they were following all along the clean syrup, they were rejecting the imidacloprid.

Miguel: Just one thing to try to explain a little bit the ethic of the why this happened, they avoid, what we think and have been shown more or less in so many studies is about the function of the microbiota. Microbiota is providing an essential component in the nutrition like amino acid and fatty acids. These have one direct effect on the immune system and the detoxification system. When there is no microbiota or it's not right, the composition, the immune system, and the detoxification system is weak, so they make more susceptible to the bees. Maybe this is why they avoid the sugar with the imidacloprid.

Kim: Good term. Interesting. It's encouraging to some level because you've got bees out there that are I don't know if I should say smart enough not to eat this stuff or their experience says this other stuff is better. However, the choice is made I'm glad at least some of them are making it.

Mohamed: Kim, if I may jump here a little bit quickly. What you said is very interesting. We don't know, in fact, but it has been studied in other insects. Are those bees smarter or like Miguel said, they have a microbiota that is not developed enough then it is not letting them survive better and detoxificate the product? The choice in my opinion is more behavioral. There is something called post aversion response in insects. It was studied on other type of insects and it's also in bees, is that when you eat something-- let's go, okay, you get some, I don't know, Coca-Cola or whatever, any drink, then each time you take that drink you feel bad in your stomach and "Ah, I don't feel well." Then next time you go to the shop, you know what? I experienced that drink, it was making problem my stomach, so I'm going to buy something else. What they did is in other insects it was studied, they tried the syrup and then they have a malaise. What we call a malaise like I don't feel good. Then sometimes they can push the syrup out or they will form a slight experience and memory about the smell of the syrup that give them previously some trouble.

They will avoid it. Of course, they don't have a long-term memory, they have short-term memory, which they can keep for some time, so we don't know exactly what's going on here. I think we need to study more that. Bees, they have extremely powerful sense of smell with their olfactory receptors. They are very, very sensitive to slight difference in smell. Our study showed in fact that they can distinguish between five ppb of imidacloprid. This is very low. We're talking about five-part per billion of imidacloprid. If they can sense this amount, that tiny amount, this is just amazing, which is evidenced in our study.

Kim: One of the things as I was reading through this that I was wondering about is you've got these winter bees who have been around a long time and their preference seemed to be headed almost exclusively towards the solutions that had the image of culprit in them. My question in the back of my head that I didn't get answered was maybe that's all they know that's food.

It tastes like this because that's all they've ever experienced. Could this have been the clean stuff, the good stuff over here didn't taste good because I've eaten my whole life the stuff that has in it all the time? Is that a possibility?

Mohamed: The winter bees, which is really interesting in fact because they were sticking no matter what to the imidacloprid. Even you, we changed the syrup, we left the clean syrup straight ahead like crazy to the imidacloprid at both concentration, 20 and 5 ppb. They like it. I don't know what? I mean, but they like it. I think Miguel has a reason.

Miguel: Mohamed, maybe I have different idea than you have maybe.

Mohamed: It's different than mine, I guess, because we had this discussion. I'll let you-- It's interesting in fact this idea. Go ahead, Miguel.

Miguel: The thing is I am physiologist, insect physiology. Everything I saw under this point of view, so for me the bees avoid the imidacloprid because they don't have the enzymes to the toxic case to break this toxin. Does it happen with the winter bees? Winter bees, they have the microbiota already. They have mechanisms to extend lifespan like the queen. In some way they are similar to the queen.

Both queen and winter bees have different molecules that are similar like more vitellogenin and vitellogenin means jaw protein is a good cholesterol for human. This a good indicator of the health. Winter bees and queen have high levels of vitellogenin that is good, is one antioxidant. I think this has been a selection for a long life, extension of life in winter bees. Be resistant to different stressor is one of these characteristics. This is my point of view.

Mohamed: I agree, Miguel, but I want to tell Jeff and Kim something very amazing. I don't know if you guys were able to spot it from the paper, but despite drinking more imidacloprid and liking it, like McDonald's, we liking it.


Mohamed: Despite that, they survived better than the other bees which avoided the imidacloprid. The theory of Miguel is, I really endorse this theory because they have more robust detoxification machinery apparently where they can decompose and metabolize this product in a much more efficient way compared to the summer bees, whether they are hatched in the lab with weak microbiota or whether they are hatched in hive with relatively fair developed microbiota.

Now, my theory, my personal theory, [laughs] I know Miguel may not fully agree, but that's fine. Winter bees, they've been around for a while, guys. Why? Because if we assume that they are the last set of brood produced by a hive, which is the case, everybody agrees I think on that, they are the last set up of brood produced in the late summertime. They are out.

They had the ability to go a little bit out forage. They've been doing their tasks here and there and they've been exposed to imidacloprid. They've developed a strong microbiota. They have different level of vitellogenin and major royal jelly protein and the physiological genes that we call-- They already are full of fat and they are ready to winter like the polar bears.

They eat a lot, and then hibernation, guys. Those are the same thing. Having said that now, they have all these characteristics and then they've been exposed definitively in the field of neonics are everywhere. We've been spraying neonics for the last 20 years. No matter what you do, they will be around. They are encoated seed crops. They are spread three times up to six times in cotton, soybean everywhere.

They've been exposed to that. Why they choose to drink from the imidacloprid is because they've been already familiarized with this taste. They've seen it before. It's like, "I'll give you a drink." "Oh, you know what? I had this drink in Italy," or, "I had this drink in France or somewhere." I remember that. I mean, I'm very familiar with it. It's exactly in my opinion, this is the case.

Since they are able to distinguish that little, tiny amount in a one-to-one sugar syrup, which is five PPB, imagine five PPB is nothing, guys. If you have one billion dots, you are adding five dots only of imidacloprid. It's nothing. They are extremely sensitive. They are picking it and they said, "You know what? I like this one. It's different in taste. I'm going to drink from it."

Now, we still have stuff to dig here because, as I said, what is really amazing is that they've drunk more of tinted imidacloprid at both concentration and they survive better than [chuckles] both other two categories. We still have a lot of stuff to explain here and to see what's going on here, in fact. We have a very good lead here in our work.

I want to add something very important we tend not to discuss it, which is the control. The control sometime you can say, "Oh, it was random, or I don't know what happened." They preferred this side better than the other side. Maybe you guys were wrong. What we did in every single experiment is we give them those two controls. Remember at the beginning of the talk I spoke about two controls.

We give them these two controls. Each time those two controls, they were consuming randomly the same amounts, which means that there is no doubt whatsoever that there is an effect on their preference and on their choice in every single experiment that we've conducted, whether for each of the three categories and for each of the two different concentration of imidacloprid.

Kim: Jeff will have a link to this paper on the webpage so people can delve into this. If I may, I want to sum this up in one sentence from this. It seems that the longer you live, the chances are you're going to live even longer as opposed to you start out young and you get introduced to this stuff you're not going to not be around much longer. I'll leave it at that.

I want to bring up one quick thing very briefly that we'll also have on the webpage is that you were looking at insulated hives for wintering. Since we're both talking about winter bees here, I thought I'd bring that up. That was an interesting study that you did on that one also. Can you tell us just briefly a little bit about it so people can go get it?

Miguel: We want to compare typical colonies, wood colonies with polyurethane colonies. Especially we were interested in the effect winter, how the cold and humidity is affecting these colonies. What's assumed that polyurethane were more better in keeping better temperature. We did a study in which we actually verified that with very precise measurement of the temperature and the humidity with tone sensors.

Mohamed: Basically, the idea was to improve beekeeping. We are losing a lot of our colonies in the wintertime. I think the average was last year catastrophe. It was 50%. I was in a conference in Georgia last week. I've heard it's 50%. We are losing half of our hives just for winter mortality in the US. How we can help? Well, we've tested those synthetic hives that some vendors are selling the polyurethane hives.

We said maybe they can provide better insulation in the wintertime. If you provide just a tiny little bit better insulation, you might save bees from starving, for example, if they're run out of storage of syrup in the winter. Maybe, maybe a couple of days would make a big difference if they have at least in our area here, they have some sunny days where they can go out and forage a little bit, sustain themselves just for the early spring.

It might make a big difference. We tested a set of polyurethane hives versus wooden hives. We've put sensors inside of temperature and humidity. We've monitored the weight. No, in that study we didn't monitor the weight. We're monitoring the weight in that ongoing study currently. Basically, we tested that and we've shown so far in the wintertime, the polyurethane hives are providing a better insulation than the wooden Lingus troth classic hive that everybody's using. That was really, and they are providing also a better, a more optimal level of humidity that was done only in the wintertime, guys. we started the experiment, I think, in November and then we ended it in maybe February or something like that. I don't recall exactly. In the winter time on 20 colonies, we tested 10 by 10, 10 polyurethane, 10 wooden Lingus trove classic stuff. We had better insulation with the polyurethane colonies.

Now it's a matter of preference too. Some people they will tell you I don't like that polyurethane, I prefer my classic wooden stuff. You've got also the commercialization, the preference of the beekeeper, but for our target was really to see if they can insulate better because the insulation level of this material is really more efficient than the wood.

Kim: That just makes perfect sense, and now you've got numbers to prove it. That's the first good step. Jeff will have that paper on the webpage, is that correct?

Jeff: We'll have links to both those papers.

Kim: Well, guys, what did we miss here that's important that beekeepers know that might give them a leg up on how to deal with pesticides in the real world?

Mohamed: I studied pesticide a lot, and I studied pesticide in France. I studied pesticide in Canada, in the US, in Tennessee, and Mississippi and especially not all pesticide. Pesticide is a big word. For us as beekeepers, we should be really concerned about the neonicotinoids and particularly those just the neonics because herbicides and other type of pesticide they are not very toxic to bees. They are toxic for other insect, but for bees it's really just the neonics. They are extremely toxic to bees, and that's why we run our study on imidacloprid. Your question, Kim, is huge. It's a huge debate the question of pesticides, everywhere. What we need to do is we run very interesting experiments in Tennessee to test how-- to really show how pesticides is affecting bees and the landscape where you put your bees, whether you put them in an area with a lot of crops or whether you go in the jungle, you put them in a forest area. We've tested that. We've published a lot on that topic.

No matter what you do, they need to eat something, they need to eat from outside, they need to eat from the pollen, they need to eat from flowers, they need that, and then also at the same time, farmers, they need to treat their crops. It's a survival matter. Both parties has to work together. Both parties have to work together to find a consensus and a common ground where a farmer will thrive and farmers will have to thrive and have their best management control program running, and beekeepers can also have their bees foraging in a safe environment, so this is the bottom line in my opinion.

Kim: It's a good bottom line. I think the right phrase there is working together, is something we all need to do, be better at to make this work for everybody. Anything else, Jeff?

Jeff: No, I think I am on full. This is a lot of great information, and I look forward to hearing more from Mohamed and Miguel in future papers. Thanks a lot, guys.

Mohamed: Wow. Thank you very much for having us.

Miguel: Thank you.

Jeff: I have a headache after listening to that. There is a lot of detail in their research. You said you read the paper, what, 11 times or so? I'm going to have to go back and get caught up to you because I can't say--

Kim: Imidacloprid. Yes, the research paper itself was 11-- or was 20 pages long and for a research paper, there's a lot of graphs and charts, but the charts are very informative, and you can get 95% of what you need to know off the charts without having to read all of the statistics and the design of the research. What they showed was one of the things that beekeepers can take away from this is were their bees exposed to imidacloprid earlier in the season so that they've developed some, I use the word carefully, immunity to this stuff so that when they go into winter and they're eating this stuff because that's all they've got to eat, they're going to survive. As opposed to those new bees that haven't any experience eating in imidacloprid, eat it once or twice and die. You throw that into the mix with mites and viruses and everything else, and you've got a problem. I'm not sure what beekeepers can do to change their management style to make that happen, but at least they've got it in the toolbox.

Jeff: Well, knowledge is key, right? If you at least are aware of what your challenges are, you can at least make even minor changes to management practices. As they say in some of the sports, marginal gains they add up and can make a difference.

Kim: I encourage people to get the paper. The link I know will be on the webpage, and I guess there was-- there might be some issues with getting the paper about the insulated hive, but the one on pesticides is going to be there. Download it, read it, and look at the pictures, and you'll get a good feel for the work that these guys did. It's really pretty and phenomenal.

Jeff: Well, that about wraps it up for this episode. Before we go, I want to encourage our listeners to rate us five stars on Apple Podcast. Wherever you download and stream the show, your vote helps other beekeepers find us quicker. Write a review and let other beekeepers looking for a new podcast know what you like. You can get there directly from our website by clicking on reviews along the top of any webpage.

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[00:46:48] [END OF AUDIO]

Dr. Mohamed AlburakiProfile Photo

Dr. Mohamed Alburaki

Scientific Researcher

Dr. Alburaki is currently a Research Scientist at the United States Department of Agriculture (USDA) Bee Research Laboratory (BRL) in Beltsville, Maryland. He is a longtime beekeeper and practiced beekeeping in many countries. He obtained his Ph.D. in honey bee genetics and behavior from the University of Pierre and Marie Curie, Paris – France. Dr. Alburaki conducted extensive studies on honey bee diversity, evolution and functional genomics during his Post-doctoral Researcher and investigated the effect of pesticides on honey bee health in Canada and the USA.

Currently his Lab at the USDA-ARS focuses on studying the effects of biotic and abiotic stressors on honey bee health and how to mitigate their negative impacts on bees. His team also investigates the causes of queen failure and poor performance from an ecological and genetic perspectives. Dr. Alburaki is also interested in develop molecular markers and novel eco-ethological methods to evaluate honey bee adaptation to local climate, forage and environmental conditions. His Lab’s ultimate objective is to develop sustainable strategies to promote and enhance honey bee health and performance in contemporary agricultural ecosystems.

Dr. Miguel CoronaProfile Photo

Dr. Miguel Corona

Dr. Corona is a graduate of the University of Guadalajara, Mexico. He completed his Master's and Ph.D. at the Biotechnology Institute of the National Autonomous University of Mexico (UNAM). He pursued postdoctoral studies at the University of Illinois, United States, and the University of Lausanne, Switzerland.

Since 2011 he has worked at the United States Department of Agriculture's (USDA) Honey bee Research Laboratory in Beltsville, Maryland. During his career, Dr. Miguel Corona has studied the processes of caste determination, queen longevity, and division of labor in bees and ants. Currently, his main lines of research are related to bee nutrition.