Jay Evans – Bee Culture https://www.beeculture.com Mon, 10 Jul 2023 12:00:39 +0000 en-US hourly 1 https://wordpress.org/?v=4.9.23 https://www.beeculture.com/wp-content/uploads/2022/07/BC-logo-150x150.jpg Jay Evans – Bee Culture https://www.beeculture.com 32 32 Found in Translation https://www.beeculture.com/found-in-translation-39/ Sat, 01 Jul 2023 12:00:37 +0000 https://www.beeculture.com/?p=44907
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City Bee, Country Bee
By: Jay Evans, USDA Beltsville Bee Lab

In Aesop’s fable, City (Town) Mouse, Country Mouse, a city mouse regales her skeptical country cousin with a rosy view of high density living. Sampling both, the country mouse prefers to stay put, largely because “the country mouse lives in a cozy nest at the bottom of a tree. Her home is small, but it is warm and comfortable.” Plus… no cats!

Beekeepers and bee scientists like to contrast the lives of bees under our care in apiaries (dense cities of colonies) versus those out on their own in trees. Aside from giving general insights into bee biology, these comparisons can predict the risks of managed and feral bees sharing disease while also showing how well ‘city’ and ‘country’ bees deal with various stresses. We have great data for the numbers of managed colonies, but how many country bees are we talking about?

I have discussed before the achingly beautiful (and hard) work by Tom Seeley and students assessing feral bees in a U.S. forest. Borrowing from those and similar studies, we can get a rough estimate of how many country bees there are in hollow trees and other cavities. My Sunday afternoon and small brain can’t grapple with honey bee density in deserts and the vast tundra, but considering four adjoining states (New York, Pennsylvania, Maryland and Virginia) with decent land-use data from the USDA (https://www.ers.usda.gov/data-products/major-land-uses/maps-and-state-rankings-of-major-land-uses/), we can estimate ‘suitable’ acreage (fallow fields, pasture and forests) at around 58 million acres total (60% of the available land). Using consensus estimates of 2.5 colonies/square-mile (one colony/square kilometer, 0.004 colonies/acre), one arrives at 233,000 feral honey bee colonies in these four states. According to USDA (https://www.nass.usda.gov/Surveys/Guide_to_NASS_Surveys/Bee_and_Honey/) ,there were 67,500 managed colonies in these states on January 1, 2021, surveying beekeepers with five or more hives. Even doubling this number to account for backyard beekeepers and those who evade surveillance, there are still fewer managed than feral colonies in these regions.

So, free-living bees are likely to be important for their own sake, and for the environment. What’s it like out there? Taking a disease angle, several studies have compared the relative disease loads of managed and feral colonies in the U.S. Amy Geffre and colleagues from San Diego sampled boxed and free-living colonies (three colonies each) seven times over the course of a year to measure virus levels for three common bee viruses (Preliminary analysis shows that feral and managed honey bees in Southern California have similar levels of viral pathogens. 2023. Journal of Apicultural Research, 62:3, 485-487, DOI:10.1080/00218839.2021.2001209). Both colony types were remarkably similar in virus levels, changing with the season but hardly differing from each other.

In Persistent effects of management history on honey bee colony virus abundances (2021. Journal of Invertebrate Pathology 179:107520, https://doi.org/10.1016/j.jip.2020.107520), Lewis Bartlett and colleagues found similar patterns between free-living and managed colonies but noted that the style of management might play a role. Namely, colonies maintained in a larger commercial apiary (hundreds of colonies) tended to have the highest levels of most viruses, with feral and low-intensity ‘backyard’ colonies being about the same. As in most field studies, there is abundant variation for viral disease within each category, so these results will need even more sampling to see how viruses and bees fare under different management styles. Nevertheless, they suggest that beekeepers adopting a ‘country bee’ approach by spacing out colonies to reduce urban interactions will be doing their bees a favor.

In the most ambitious study to date, Chauncy Hinshaw and colleagues surveyed 25 colonies each from feral and managed colonies in Pennsylvania (2021. The role of pathogen dynamics and immune gene expression in the survival of feral honey bees. Frontiers in Ecology and Evolution, 8, 594263. https://doi.org/10.1080/00218839.2021.2001209). They surveyed ample bee numbers per collection (75 worker bees), perhaps getting a better sense of average disease loads. Even better, they paired similar city and country colonies from a bunch of regions, which helps account for other factors that might change virus loads. In this study, managed colonies tended to have lower levels of mite-transmitted deformed wing virus, presumably reflecting mite treatments, and roughly similar levels of black queen cell virus and nosema. Perhaps reflecting pathogen exposure, feral colonies had higher levels of several immune response proteins as well. Given the higher number of sampled colonies, these researchers were also able to show how their measurements related to colony fates. As in prior studies, deformed wing virus, presumably alongside mite loads, was a good predictor of a bad colony outcome.

Colonies showing higher levels of two immune genes, once other factors were evened out, were more likely to survive the study period. Arguably, these proteins might be good predictors of genetic components that help bees survive in the face of disease.

More can be done to contrast the lives and successes of city and country bees. These comparisons can help improve bee management by those of us keeping bees in clusters of Langstroth high-rises. It is also fun to think of bees in the ancestral habits they have followed for thousands of years. Country bees almost certainly have more threats now than they did when humans were more scarce, and there has to be some level of contact between city bees and country bees that muddies all of these comparisons, but in many ways the presence of country bees at all is comforting. Left to their own care, they are making country homes work wherever they can, and that is a good lesson for beekeepers.

In full disclosure, the lives of country bees were not on my mind until a recent inquiry from British bee researcher Francis Ratnieks and his graduate student Ollie Visick. In their Laboratory for Apiculture and Social Insects (https://www.sussex.ac.uk/lasi/), they are comparing the lives of free-living honey bees in their native range to their hived cousins. As ecologists, their studies will give insights into how honey bees used to live in the forests and fields of England. I thank them for the prompt (and welcome hot tips from any of you) and look forward to reading their results!

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Found in Translation https://www.beeculture.com/found-in-translation-38/ Thu, 01 Jun 2023 12:00:19 +0000 https://www.beeculture.com/?p=44692 https://www.beeculture.com/wp-content/uploads/2023/06/EvansFoundTransJune2023.mp3
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Found in Translation

Teaching Bees New Tricks

By: Jay Evans, USDA Beltsville Bee Lab

Bees have innate (think ‘robo-bee’) and learned (‘show me, sister’) behaviors. Recent work with bees has explored the boundaries of these two forms. While it is dangerous to put our own biases on animal behaviors, the complex behaviors measured seem to include ‘play’, ‘puzzling’ and ‘dancing’. Oh yeah, and they can count as well, even showing an awareness of ‘zero’ things, but that was yesteryear’s news from Scarlett Howard and colleagues (Numerical ordering of zero in honey bees, 2018, Science, DOI: 10.1126/science.aar4975).

What is fascinating about work coming out just this year is that not only do bees show complex behaviors, but they seem to get better at those behaviors by watching their nestmates. Bee dances will be familiar to most beekeepers and students of animal behavior. Successful foragers often tell their sisters where the good stuff is after finishing their foraging flights. Specifically, foragers signal both direction and distance to flower sources using the waggle dance. True to its name, and shown graphically to the right, this dance involves a bee streaking across the comb and shaking its abdomen for the edification of sister foragers. The angle of this dance on a vertical patch of comb signals the direction of a good food source relative to the current position of the sun relative to the hive. The length of each dance streak provides an estimate of the distance to flower patches (or to sugar baits planted by curious naturalists). By repeatedly dancing, they drum up interest and lead future foragers to a better understanding of how far they might have to fly to get these rewards. The discovery of this dance language is decades old, and justified a share of the Nobel Prize in Physiology or Medicine in 1973 for Austrian bee researcher Karl von Frisch. The recent work ups the game by showing that much of this behavior is learned by watching older, more precise, dancers.

Shihao Dong and colleagues set out to study Social signal learning of the waggle dance in honey bees (2023, Science, DOI:10.1126/science.ade1702). Specifically, they judged the dancing skills of self-starters relative to those of bees that were mentored by older, experienced, dancers. To produce a swarm of naïve dancers, they established colonies comprised solely of like-aged bees, so that all bees reached foraging age together and were therefore less likely to benefit from matching the skills of a senior dancer. Bees from these ‘Animal Farm’ colonies were compared to marked bees of the same age which had grown up gazing at the dances of experienced dancers in colonies with a typical age profile. Naïve bees consistently over-stated the distance they had flown to flowers, in effect telling nestmates to fly right past suitable food sources. They also showed more ‘Dance Disorder’ than both older bees and bees that had been exposed to older dancers. Dance accuracy for all dancers improved over time, it just improved much more quickly when bees had older mentors to watch. So what is the lesson here for beekeepers? No, you can’t force your teenager to watch you dance and expect them to get it, but you CAN see how bees in colonies with an abnormal age structure, thanks to rapid premature death of foragers, might continue to slide by spending unnecessary time looking for food. Long-lived bees are those free of chemical stress, raised with adequate protein nutrition, and arguably bees that have avoided mites and other disease. When you protect your bees from these stresses, just think of how their dance lives will improve.

In a study that, for me, deserved two SMH’s, bees were trained to take on puzzle behaviors, or behaviors that simply don’t present themselves to bees when scientists aren’t around. Working with bumble bees, Alice Bridges and colleagues first taught their bees to open small food boxes by pushing on colored (red or blue) tabs. This a behavior I am not sure I could teach my dog, but she is a bit slow. They then checked to see if bees could follow the lead of a nestmate who had already figured out the box trick. While self-learners emerged in the control colonies sometimes got the knack for opening boxes, bees who observed a nestmate open a box were more likely to successfully mimic that behavior. Over time, bees with a teacher opened more boxes, faster, and were rewarded with more sugar treats. Honey bees and some other bee species are known to spontaneously ‘rob’ flowers by chewing directly into nectar pools when those pools are too deep in the flower for their tongues to reach. It would be neat to see if such nectar robbing is also a learned trait, passed on by adventurous foragers who had to learn the trait the hard way. If so, can such teachers target their lessons to their nestmate sisters?

All of these studies push the known boundaries for bee awareness and behavior, showing all the more how lucky we are to have formed bonds with honey bees and other insects. Clever behavioral scientists will no doubt continue to discover profound, and maybe a bit unsettling, awareness by insects. This awareness is likely to be most evident in the highly social honey bees and bumble bees. What’s next, spelling bees? Stay tuned. In the meantime, get out, find a friend and improve your dancing.

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Found in Translation https://www.beeculture.com/found-in-translation-37/ Mon, 01 May 2023 12:00:16 +0000 https://www.beeculture.com/?p=44445 https://www.beeculture.com/wp-content/uploads/2023/05/Evans-BeeCultureMay2023.mp3
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Bees have an increasing say in soybeans

By: Jay Evans, USDA Beltsville Bee Lab

Farmers and scientists debate the extent to which one of our country’s favored crops, the soybean, benefits from honey bee visits. Nor are they sure that having bees visit soybean crops is a net positive for the bees. Despite research documenting strong benefits to soybeans from honey bee visits (dating since the youth of former Bee Culture editor Kim Flottum, https://www.beeculture.com/found-in-translation-19/), a perusal of thousands of studies related to soybean farming shows little emphasis on how and when bees should be deployed. As one metric, a March 2023, Google Scholar search of papers mentioning “soybean yield” and “honey bee” provided 276 references. The same search excluding the term “honey bee” provided 62,200 references. This overall trend has not improved in recent years; papers mentioning soybean yields that do not mention honey bees number 5,110 since 2022, while only 32 papers mention honey bees. Fortunately, those 32 papers provide some really important advances. The upshot is that bees can greatly improve soy production, while potentially gathering a resource for themselves and their keepers. What remains to work out:

  1. How can beekeepers practice safe soy?
  2. How can growers choose varieties and management practices that harness bee visits to boost production of a vital row crop?
  3. How can the two sides meet up to work out deals that benefit both industries and the environment?

On the soy side, honey bee pollination impacts were described this month in a freely available paper from Decio Gazzoni and João Paz Barateiro (Gazzoni, D.L. & João Vitor Ganem Rillo Paz Barateiro. 2023. Soybean yield is increased through complementary pollination by honey bees, Journal of Apicultural Research, DOI:
10.1080/00218839.2022.2161219). These authors showed that, with the right conditions and soybean varieties, honey bees increased soybean yields in controlled environments by 8.5-18.2% in four trials across three years. This increase is not as dramatic as other studies from different cultivars, but still reflects a lot of beans. Hannah Levenson and colleagues at North Carolina State University also showed recently that supporting bees merely by expanding local non-crop habitat led to a significant difference in soybean seed (bean) weights. In an exhaustive survey of 7,000 bees in the field, they found that 30+ bee species had collected soybean pollen but honey bees tended to be more faithful than others for soy versus alternatives (Levenson, H. K., A. E. Sharp, and D. R. Tarpy. 2022. Evaluating the impact of increased pollinator habitat on bee visitation and yield metrics in soybean crops. Agriculture, Ecosystems & Environment 331:107901, https://www.sciencedirect.com/science/article/abs/pii/S0167880922000500).

If bees are generally good for soybeans, are these visits doing bees any good? Chia-Hua Lin and colleagues at The Ohio State University have been on that story for some time and recently published a complex study asking whether bees 1) make it to abundant local soybean fields and 2) bring home resources for their colonies (Lin, C.-H., Suresh, S., Matcham, E., Monagan, P., Curtis, H., Richardson, R. T., & Johnson, R. M. 2022. Soybean is a Common Nectar Source for Honey Bees (Hymenoptera: Apidae) in a Midwestern Agricultural Landscape. Journal of Economic Entomology, 115(6), 1846-1851. doi:10.1093/jee/toac140). In a citizen-science twist, the scientists asked members of the Ohio State Beekeepers Association to bring honey collected by bee colonies from across the state to their Fall meeting. This honey was screened for the presence of different pollen types under microscopy. As indicated by the title, soybean pollen was commonly found in Ohio honeys. More than half of the screened honeys held soybean pollen, and this increased for honey derived from foraging in July and August, when soybean flowers were most common. Finally, the authors used the waggle dance, the signal bees use within their colonies to direct nestmates to good foods, to show that returning bees are eager to tell their nestmates about soybean rewards. For medium-distance flights, returning bees were more likely to ‘dance’ that they had visited soybean fields than other fields, complementing the pollen collection data and saying that bees preferentially target soybean fields over the alternatives. Dr. Lin has backed up this work with some truly remarkable studies covering the attractiveness of dozens of soybean cultivars to bees in common gardens (e.g., https://ohiocroptest.cfaes.osu.edu/soy2022/2022_OSPT_pollinator_report.pdf) and is working relentlessly to improve cross-pollination between beekeepers and soybean growers.

Team B & B (Bees and Beans) collecting flowers in soybean plots last Summer. The white stakes are Karlan Forrester’s audio recorders. Photo provided by Chia-Hua Lin from the Rothenbuhler Honey Bee Lab at The Ohio State University

In ongoing work, graduate student Karlan Forrester (working with Chia-Hua Lin and Reed Johnson at Ohio State), has worked out innovative methods for tracking bees as they zero in on soybean flowers, while also confirming that certain soybean varieties are more rewarding, and hence attractive, to discerning bees (Forrester, K. C., Lin, C.-H., & Johnson, R. M. 2022. Measuring factors affecting honey bee attraction to soybeans using bioacoustics monitoring. BioRxiv, 2022.2011.2004.512777. doi:10.1101/2022.11.04.512777).

In looking for soy-bee stories that describe ways to enhance this partnership, I came across a series of fascinating works from the other side of the world. Dr. Dolapo Bola Adelabu, a researcher from the Free State of South Africa, and his colleague Angelinus Franke, found remarkable increases in soybean yields that can be attributed to visits by bees and other pollinators (Adelabu, D.B., Franke, A.C. 2023. Beneficial Role of Pollination and Soil Fertility for Soybean Production in Mountainous Farming Conditions. In: Membretti, A., Taylor, S.J., Delves, J.L. (eds) Sustainable Futures in Southern Africa’s Mountains. Sustainable Development Goals Series. Springer, Cham. https://doi.org/10.1007/978-3-031-15773-8_5). These yields were greater than 50% when combined with optimal fertilizer supplementation of crops (Nitrogen and Phosphorous), with less striking increases under poor soils. Farming in this region of southern Africa, in a rugged corner of the Free State, is distinguished by “smallholder” farms, where farms are interspersed with homes and natural areas. This farming scheme allows for both wild bee habitat (honey bees are not routinely kept in hives here) and presumably a range of alternate food sources for bees when soybeans are not in flower. In conversing with Dr. Adelabu, the studies did not distinguish Apis mellifera from other bee species, but it seems likely that honey bees were a major member of the pollinating community. Thanks to this research, the services bees provide in terms of local soybean yields, among other crops, justifies the work needed to keep healthy bee habitat. The two scientists in this work are also more broadly interested in schemes to provide healthy nutrition to a fairly dense human population, while maintaining a sustainable environment, ( e.g., https://www.ufs.ac.za/aru/aru-team/aru-team/prof-angelinus-franke). Hannah Levenson phrases it well in her article, “As such, pollinator habitat should be designed to provide resources across the entire active season to help these important pollinator populations, especially since many crops have short bloom durations.”

One hope from all this research for the U.S. will be improved dialogue between beekeepers and soybean farmers, ideally driven by profits on both sides. This dialogue will help bees collect soy flower resources while minimizing collateral damage from agricultural practices, including the need to treat for crop diseases and insect pests. In the meantime, what are the best practices for beekeepers around soybean farms? The Honey Bee Health Coalition has focused on this issue, leading to a draft of guidelines led by Adam Dolezal at the University of Illinois showing how management practices, from pesticide applications to habitat, can be more bee-friendly (https://honeybeehealthcoalition.org/resources/soybean-best-management-practices/). Making more food on fewer acres is good for the planet and the economy, and it is great that scientists and farmers on both sides are tackling the soy-bee system in a rigorous way.

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Found in Translation https://www.beeculture.com/found-in-translation-36/ Sat, 01 Apr 2023 12:00:30 +0000 https://www.beeculture.com/?p=44049 https://www.beeculture.com/wp-content/uploads/2023/04/EvansFoundTransApril2023SocialNature.mp3
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Found in Translation

Social Nature and the Hive Life

By: Jay Evans, USDA Beltsville Bee Lab

Picturing the Spring that will be upon the northern hemisphere when this essay is published, I feel a deep longing to see our bees in full growth, bringing back diverse pollen baskets and crops full of abundant nectar. Spring is my favorite season and it is almost painful to think of it as I write this in February (to many of us, the longest month). As a passionate beekeeping ally, I firmly believe that on the whole and in most settings honey bees are not only a tremendous asset to humans but intrinsically worthy in their own right. As messy as it might seem, this is true in both their introduced and native ranges (Eurasia and Africa for the ‘western’ honey bee).

Except for one 14 million-year old flattened specimen that fossil-hunters feel is in the genus Apis (all species of which have comb-forming, stinging, honey-storing social habits), there is no firm evidence that honey bees lived in North America before European colonists arrived a few centuries ago. Once here, however, honey bees flourished, swarming from their woven homes and making themselves an important part of both agricultural and natural habitats. In the midst of Winter, I feel the need to celebrate this flourishing.

That said, this is not another economic essay on the value of honey bee pollination or colony products, although $20-25 billion added to the U.S. economy in diverse, nutritious foods is not trivial. Nor is it another diatribe that bee-mediated pollination nourishes people throughout the world, nor that honey bees provide a cash crop for millions of families, with little startup costs, in communities that are stressed for both cash and nutritious foods.

And this is not a tribute to all the hardworking beekeepers, with from one to 80,000 colonies, who battle a variety of stresses to stay in the game (though I am not above pandering to that crowd).

It’s not even a worshipful look at how pollinators have shaped our world over 100+ million years, not simply by supporting billions of humans but in making every landscape just a bit more colorful and dynamic. This collaboration between bees and flowering plants, which started early and ended well for both, is wonderfully described by Sophie Cardinal and Bryan Danforth in their 2013 paper Bees diversified in the age of eudicots, Proceedings of the Royal Society B, https://doi.org/10.1098/rspb.2012.2686. I will tackle the larger economic and environmental benefits of honey bees and other pollinators in the future, this essay is more personal.

I would argue that we socially aware humans just need honey bees beyond their great services. To me, this need comes from two drivers. First, honey bees mirror our own inescapably social natures and teach valuable lessons therein. Second, if you try even half-heartedly to place yourself in the mindset of honey bees and other pollinators you can’t escape thinking about, and striving to improve, the plant resources and the overall environment they fly over and visit on their foraging flights.

First, the social connection. It is easy to revere a species in which selfless workers provide for relatives they most likely will never meet. There are so many facets of honey bee communication, biology and nature that are mirrors for our own, leading to profoundly interesting behaviors that resonate with the good and bad of our communities. My gateway to social insects and ultimately a life studying honey bees opened with a single lecture by an ant biologist, after which I went to my dorm and decided it was inconceivable to fritter my life away without studying these special creatures who build empires largely because they choose, 90% of the time, to drop their conflicts and work for a common goal. Ignoring their preferred diets, ants and honey bees are quite similar. Most importantly, both have succeeded in no small part because they divide tasks efficiently in colonies and can thereby both out-compete their solitary neighbors and regulate their home environments. Thomas Seeley’s book The Lives of Bees: The Untold Story of the Honey Bee in the Wild (2019) is a great entry into the wonder of bee inner worlds, while German professor Suzanne Foitzik shares similar life stories for ants in her 2021 book Empire of Ants: The Hidden Worlds and Extraordinary Lives of Earth’s Tiny Conquerors. In my case, the itch to learn about social insects became a full-on rash after opening a small student beehive for the first time while devouring the many stories of how honey bees and humans have been partners for thousands of years. From “busy as a bee” to “dance language” and “guard bees”, how we think of bee societies is hard to decouple from how we view our own. Not surprisingly then, neither bee nor human societies are perfect. Both show conflict within, vulnerabilities to parasites of all sorts and an occasional tendency to trample other beings, but both are marvels to behold, and exhilarating to compare and contrast.

A second preeminent reason to value honey bees is that they truly provide a gateway to understanding nature. When beekeepers see their bees exit the hive, circle-wave their home and sail off, they marvel at what that tiny bee will see on a journey across the landscape, wishing the bee luck and the memory cells to return after a successful foraging trip. This care for one’s bees inevitably leads to a greater appreciation for the flowering world, leading beekeepers to seek ways to improve and diversify the green world their bees encounter. Beekeepers fret over, and are noisy about, any ill winds that arise from degraded environments within two miles of the colonies they host. Habitat loss, climate, land practices and disease all impact the health of honey bee colonies, and beekeeping forces us to learn about each of those topics. Every beekeeper also has a keen sense of weather and the seasons. Okay, the same is true for gardeners, birders and hunters… and by some stretch of the imagination even golfers, although better if they let their ‘greens’ revert to wildflowers. Similarly, beekeepers are among the most knowledgeable humans with respect to how diseases spread, how to slow infections, and when it’s time to seek a doc, even if we neglect that knowledge sometimes with our own health and that of our colonies.

It’s not an easy path, and beekeepers often stumble. But, bees and beekeeping give back incredible riches to those who listen to the buzz and hitch a ride with their bee teachers. Hope springs eternal and here’s hoping your Spring is bountiful.

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Found in Translation https://www.beeculture.com/found-in-translation-35/ Wed, 01 Mar 2023 13:00:28 +0000 https://www.beeculture.com/?p=43910 https://www.beeculture.com/wp-content/uploads/2023/03/EvansFoundTransMarch2023BeeGood.mp3
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Found in Translation

Bees Good

By: Jay Evans, USDA Beltsville Bee Lab

Waiting for Spring makes one hopeful and, simultaneously, a bit reflective on why we all keep at this, despite heavy Winter losses and expenses. This year, massive floods in California will wreak havoc with bees and beekeepers in holding yards and during the first commercial stop of the year in almond plantations. Most years the opposite is true; crippling droughts decrease yields from almonds and other crops, diminishing the agricultural benefits of bee pollination. Still, most of the time, bees and beekeepers get a break and honey bees and other pollinators provide a solid boost to the production of healthy foods. This essay is devoted to the bees and beekeepers whose actions improve food production and human welfare.

Our sister branch of USDA, the National Agricultural Statistics Service (NASS), provides quarterly and annual views showing how honey bees impact humanity in the USA (https://www.nass.usda.gov/Surveys/Guide_to_NASS_Surveys/Bee_and_Honey/index.php). These reports document how the hard work to keep bees alive pays off in the farming economy and the food supply. Jennifer Bond and colleagues at the USDA’s Economic Research Service pulled data from NASS and other sources to generate a full view of the bee industry and its drivers in Honey Bees on the Move: From Pollination to Honey Production and Back (2021, https://www.ers.usda.gov/webdocs/publications/101476/err-290.pdf). This short book shows the challenges faced by beekeepers and the targets that keep them on their toes, highlighting that 80% of annual pollination income to beekeepers is derived from one early-season source (almond plantations, flooded or otherwise). Bees and their migratory keepers then disperse widely for additional pollination events and, weather and habitat permitting, the production of honey and wax. Overall, beekeepers receive $320 million in pollination fees for their efforts, and these efforts have a twenty-fold greater impact on U.S. crop production.

Pollination of crops not only provides an economic engine for growers and (some) beekeepers, but pollination by bees is literally saving lives. A recent global analysis generated values for pollination impacts on world crops by estimating decreased productivity when bees were limiting (Matthew Smith and colleagues, Pollinator deficits, food consumption, and consequences for human health: A modeling study, 2022, Environmental Health Perspectives, 130(12) 127003-1 https://doi.org/10.1289/EHP10947). By looking at peaks versus observed productivity across farmed regions, the authors estimate that inadequate pollination decreases yields for fruit and nut crops by 5%, on average. Similarly, vegetable yields are reduced by 3%. These estimates cover 60+ crops that supplement the diets of billions of people on all continents except Antarctica. Using conservative measures, the authors estimate that 500,000 people die annually due to decreased food yield or quality caused by missed pollination events by bees. This human toll differs across countries, with some populations suffering from all-out hunger and malnutrition while others (including the United States) are impacted more by shifts in diet tendencies away from more nutritious pollinated crops such as fruits and nuts. In a second recent paper (Pollination deficits and contributions of pollinators in apple production: A global meta-analysis, 2022, Journal of Applied Ecology, DOI: 10.1111/1365-2664.14279), Aruhan Olhnuud and colleagues present data for one critical worldwide fruit (the apple) and argue for even greater impacts of missed pollination on yields and seed set, in the range of 40% and 20%, respectively, much higher in some countries. Seed set for apples does not limit the industry overall, but fertilized seeds lead to a more attractive fruit shape. Honey bees, of course, are not the only insect pollinators of crops and both of these papers take great pains to account for the impacts of diverse pollinators. Nevertheless, in many counties, including ours, honey bees are the primary pollinators of crops, especially for larger farms.

While these studies focused on pollination impacts, honey bees provide a bounty for beekeepers small and large that was not accounted for in these two studies. The nutritious value of honey, and to a lesser extent pollen and brood, improves nutrition in many countries. Further, the receipts from honey and wax sales have a huge impact on human health worldwide and are arguably one of the most important sources of small-farm income in developing and industrialized incomes. Bernard Phiri and colleagues analyze yields from hive products worldwide in Uptrend in global managed honey bee colonies and production based on a six‑decade viewpoint, 1961–2017, 2022, Scientific Reports 12:21298, https://doi.org/10.1038/s41598-022-25290-3). This fascinating synopsis highlights the losses and (mostly) gains of beekeeping across continents alongside the economic and population drivers behind those changes. As has been well documented, North America has seen a 30% decrease in honey bee colonies since 1961, while Europe (including Russia) has lost 12% of its colonies. South America, Africa, Australia and Asia have more than compensated for those losses, doubling or even quadrupling (Asia) managed hives in that time frame. Overall, the number of managed honey bee hives has doubled since 1961, matching a doubling in human population. All regions have perfected honey and wax harvesting, with honey yields even in North America surpassing those of prior years, despite lower colony numbers. This North American increase reflects heavier harvests in Mexico and Canada that outweigh decreased honey yields in the U.S. (https://www.visualcapitalist.com/cp/mapped-food-production-around-the-world/). Asian countries increased honey harvests by eight-fold over this time frame. It would be fascinating to estimate how greatly honey production impacts populations worldwide, not simply in local consumption but as an attainable and sustainable cash crop in developing and more industrialized countries. My guess is that the impacts of honey harvesting on lives improved and saved from premature death would rival that achieved by increased pollination from managed hives.

Whether you are keeping bees for family munchies, selling honey on a table or fully engaged in commercial pollination and the production of hive goods, you are playing a role in an essential partnership with one of the planet’s truly extraordinary animals. Thanks for doing that.

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Found in Translation https://www.beeculture.com/found-in-translation-34/ Wed, 01 Feb 2023 13:00:49 +0000 https://www.beeculture.com/?p=43752 https://www.beeculture.com/wp-content/uploads/2023/02/EvansFoundTransFeb2023.mp3
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Found in Translation

Missing Their Better Half, More on Drone Genetics

By: Jay Evans, USDA Beltsville Bee Lab

Last month I wrote a tragic, and maybe a little droning, article about the shortcomings of male honey bees and their fragility. On a more uplifting note, drone genetics have great potential for use in honey bee breeding. Male bees, like male ants and male wasps, have half a deck of chromosomes, 16/32nds to use a precise carpenter term. These 16 chromosomes provide all of the information needed to make a bee (obviously) but with no redundancy for the most part. When there is a critical mutation in a critical gene, that bee will not fly. This liability is actually a gift in disguise for breeding and genetics in several ways.

Remember that, despite their limited job duties, not all male bees are equal. Differences among drones impact their ability to contribute genes during mating, and the value of those genes to their unseen offspring should drones win the mating lottery. Bradley Metz and David Tarpy showed that male bees in commercial beekeeping operations differed by two-fold in weight and by an amazing 100-fold in the amount of sperm they have available for mating (Metz, B. N., and D. R. Tarpy. 2021. Reproductive and morphological quality of commercial honey bee (Hymenoptera: Apidae) drones in the United States. Journal of Insect Science 21, https://doi.org/10.1093/jisesa/ieab048). By their estimate, 6.5% of adult drones in commercial operations were of ‘low quality’. To produce males matching the subpar guys, these scientists had to raise males in smaller worker cells. As expected, 83% of males raised in worker cells were graded as ‘low quality’, versus 2% of males raised at the same time in proper drone cells. Since males are unlikely to be raised in worker cells in the field, other colony or genetic factors must lead to the production of low-quality males. The usual suspects are disease, chemical stress and poor nutrition, although this study did not explore those causes. Interestingly, bee genetics can also play a role in variable drone traits, and in drone reproductive traits in particular. Garett Slater and colleagues reviewed substantial data showing that races of bees differed consistently in drone traits such as sperm count and sperm longevity (Slater, G.P.; Smith, N.M.A.; Harpur, B.A. 2021. Prospects in connecting genetic variation to variation in fertility in male bees. Genes, 12, 1251. https://doi.org/10.3390/genes12081251). While mated queens use only a fraction of the sperm received over the multiple mating events they engage in, there is some evidence that queen egg-laying is negatively impacted by mating with poor-quality males. Overall, these studies indicate the value of exposing your queens to healthy males.

Given all these weaknesses, what do males bring to the queen selection table? Being haploid means that individual males can have a disproportionate effect on offspring traits. In a hypothetical mating between a queen and a single male, the worker bee offspring are “super-sisters” in that they are identical on their dad’s side. In contrast, sisters share roughly half of their mom’s genotype (a term for the combined variants seen in a typical diploid animal). Male-driven breeding, coupled with instrumental insemination (since no one has time to direct males on the wing to precise matings), has huge potential to shift bee populations toward desirable traits. In our group, Laura Decanini led such an attempt for earlier efforts to identify resistance to American foulbrood (Decanini, L. I., A. M. Collins, and J. D. Evans. 2007. Variation and heritability in immune gene expression by diseased honey bees. Journal of Heredity 98:195-201, doi:10.1093/jhered/esm008) Starting with genetically homogeneous breeder queens, from a singly-mated Italian mom, we were able to produce a 100-fold range of immune traits when crossing those queens to a diverse set of 26 local drones. Heritability for both immune activity and survivorship in the face of P. larvae was high, as measured by comparing immune traits of resulting offspring with their ‘aunts’ from the 26 drone source colonies.

Even more powerful are attempts to screen drones themselves for desired traits, then collect and use sperm only from the drones who aced their fitness test. Ivelina Ivanova and Kaspar Bienefeld in Germany attempted to use drones as a surrogate for worker hygienic behavior, by subjecting drones to the ‘Proboscis Extension Reflex’ a common assay for learning and behavior in workers. (Ivanova, I. and Bienefeld, K. 2021. Suitability of drone olfactory sensitivity as a selection trait for Varroa-resistance in honey bees. Scientific Reports 11, https://www.nature.com/articles/s41598-021-97191-w). In worker bees, the PER can be used to assess responsiveness to the chemicals that trigger hygienic behaviors. Bees, which are smarter than most insects, will stick their tongues out for a food reward and can be trained to do so for cues like smells, learning like Pavlov’s dog to associate those smells with something good. Males in this study figured out the PER, as do worker bees, although males apparently do so with less vigor and more ‘nervousness’. Also, in the current study, “We observed a greater unwillingness of drones to respond to the CS+ and the sugar solution on cold or rainy days, although the temperature in the laboratory was regulated”, and “during our preliminary tests, we also observed high drone mortality if drones were treated according to existing bee protocols”. To go easy on these fragile males, the PER study was shortened, and the authors were able to generate usable data. Sadly, males that scored well in these standardized tests did not father the most hygienic offspring, so there was a disconnect there somehow. Still, males from high-scoring colonies helped perpetuate that trait, a validation of PER and comb-based hygienic tests for improving this key trait… but only when female bees are asked to take the test for their brothers. This does not rule out using male bees as a direct screen for individual resistance traits, including immunity. Drone-level screens of immunity followed by instrumental insemination give a direct path to stock improvement since drones fend off disease with the same immune response as their sisters. Scientists, including my USDA colleague Michael Simone-Finstrom and bee breeder Daniel Weaver, are using drone screens of disease response to enhance stock resistance (https://www.ars.usda.gov/research/project/?accnNo=441927). Drones still have time to show their strengths and it is fascinating to contemplate how being ‘haploid’ affects male contributions to colony life. Something to buzz about as we edge past the long drone of February toward Spring and colony renewal.

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Found in Translation https://www.beeculture.com/found-in-translation-33/ Sun, 01 Jan 2023 13:00:00 +0000 https://www.beeculture.com/?p=43532 https://www.beeculture.com/wp-content/uploads/2023/01/EvansFoundTransJan2023.mp3
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Found in Translation

Save the Males

By: Jay Evans, USDA Beltsville Bee Lab

Male honey bees are not afforded much respect. If a male bee had the mojo to write a memoir it would be entitled “Eat, Mate, Die: One bee’s journey toward the audible pop”. No movie options there, despite the sadists just waiting for the dramatic ending. Nevertheless, these droning lives are critical for the generational success of honey bee colonies. Recent research has explored how male bees, fragile though they might be, contribute to colony health and the longevity of laying queens. There are also new insights into how biological and environmental threats impact males and thereby colony success.

First, male bees truly do have a smaller behavioral repertoire than females. Males are also sheltered from many of the stresses faced by worker bees and long-lived queens. The typical male bee, following a leisurely 24-day development time, emerges from his roomy honeycomb cell and simply ‘lives’ for more than a week before taking his first flight from the colony. No glands to produce wax, no glands to provide buttery food for developing bees, no grooming, no feeding of others, no defending the colony. During this time, the male’s energy is funneled into massive flight muscles and impressively large testes. When scientists look at male performance, they look at these two factors; can the boys fly and can they make viable sperm?

For the first question, it is important to determine if stressed males even live long enough to fly. Recent work by Alison McAfee and colleagues from the University of British Columbia and North Carolina State University showed that drones are more sensitive than worker bees to both cold temperatures and one pesticide (imidacloprid) under high lab exposure rates (Drone honey bees are disproportionately sensitive to abiotic stressors despite expressing high levels of stress response proteins. 2021. Communications biology 5,141, https://www.nature.com/articles/s42003-022-03092-7). Specifically, most drones simply can’t endure four hours at temperatures just above freezing, while their female counterparts survive fine. In this same study, drones died at two-fold higher rates than their sisters after exposure to 100 ppm imidacloprid. When exposed to a cocktail of field-expected pesticide doses, both drones and worker bees survived fine in these trials, but the evidence that drones were disproportionately sensitive overall prevailed.

Collecting semen from a drone honey bee that will be used to artificially inseminate a queen bee.

What about sperm? Much has been written about the impacts of drone sperm quality on colony health, using techniques mastered by retired USDA scientist Anita Collins (i.e., Collins, A.M. Relationship between semen quality and performance of instrumentally inseminated honey bee queens. 2000. Apidologie, 31, 421–429, https://www.apidologie.org/articles/apido/abs/2000/03/m0307/m0307.html). But what is it, outside of the lab, that leads to inviable drone sperm? Like most traits, both genes and the environment play a role. In a recent colony-level study, Lars Straub and colleagues measured the impacts of pesticide stress on “all the things drones are asked to do” (Negative effects of neonicotinoids on male honey bee survival, behaviour and physiology in the field. 2021. Journal of Applied Ecology, 58, 2515–2528. https://doi.org/10.1111/1365-2664.14000). Drones exposed to field-realistic chemical doses via pollen patties fed to their colonies died at twice the rate of controls. When they survived, exposed drones took longer than controls to take their first flight, drifted more often to the wrong colony and produced a higher ratio of defective sperm.

Does that defective sperm translate into poor colony health? Jeffery Pettis and co-authors showed that queens heading failing colonies in commercial beekeeping operations carry a higher proportion of damaged sperm (Pettis JS, Rice N, Joselow K, vanEngelsdorp D, Chaimanee V. Colony failure linked to low sperm viability in honey bee (Apis mellifera) queens and an exploration of potential causative factors. 2016. PLOS ONE 11(5): 0155833. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0147220). Sixty percent of the sperm stored by queens in failing colonies was dead, while only 30 percent was dead in healthy colonies. This need not reflect a history of dysfunctional dads in that poor sperm health might reflect the abilities of queens to keep sperm viable rather than damaged goods from the start. In fact, the researchers found higher levels of dead sperm after queens were subjected to temperature stress, passing the blame for sperm health to queens or (more likely) queen transport and management. While it is tough to measure the longterm effects of inadequate males on colony health, headway was made with data and a model generated by Bradley Metz and David Tarpy from North Carolina State University (Reproductive and morphological quality of commercial honey bee (Hymenoptera: Apidae) drones in the United States. 2021. Journal of Insect Science, 21: 2, https://doi.org/10.1093/jisesa/ieab048). Observationally, colonies produce a range of smaller and larger drones, with six to 10% of drones being below a threshold size mimicking that seen when drones are raised mistakenly in worker cells. These smaller drones differed in their abilities to pass on adequate sperm in both quantity and quality (sperm viability), and the authors use that fact to argue that less fit males can have a strong impact on queen longevity and the health of managed bee colonies.

Weirdness in male bee genetics play some role in their fragility. Male bees, like male ants and wasps, and males found in a handful of less prosperous insect groups, are generally ‘haploid’ from birth to death. They are born of unfertilized eggs that simply start dividing into tissues and eventually organs, forming a viable insect that has no genetic father. Being haploid comes with its own set of challenges. Most life forms outside of the bacteria and ‘archaea’ have a genetic father and mother. This means we have two copies of genes that encode most of the proteins in our bodies. This redundancy can be good as organisms develop, behave and prosper. For example, many survivable genetic diseases in humans and other organisms are survivable simply because one of two viable proteins in such cases can suffice for a critical life task. As scientists have noted, honey bee drones are thus uniquely vulnerable to dysfunctional proteins encoded by their exposed genomes. The work previously mentioned, by Dr. McAfee and colleagues, for example, contrasted males and their sisters specifically to see if males were the weaker sex because they are haploid or because of other biological differences. Their study suggests the latter. Nevertheless, there are surely impacts from having half a set of chromosomes in terms of breeding and bee evolution. Garett Slater and colleagues, in Haploid and sexual selection shape the rate of evolution of genes across the honey bee (Apis mellifera L.) genome (2022. Genome Biology and Evolution. 14(6) https://doi.org/10.1093/gbe/evac063) showed that genes that were especially active in male bees were evolving differently than genes equally active in both sexes, although it is not clear that this reflects playing with half a deck. The genetic impacts of being haploid, and the potential for this phenomenon to be exploited in bee breeding, are good topics for next month. Thanks to a handful of female and male scientists who have looked past the limited behavioral range of male bees, we now have critical information on the colony and environmental factors that conspire against drones, and the impacts of drone health on colony offspring borne from their brief and dramatic lives.

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Found in Translation https://www.beeculture.com/found-in-translation-32/ Thu, 01 Dec 2022 13:00:28 +0000 https://www.beeculture.com/?p=43260 https://www.beeculture.com/wp-content/uploads/2022/12/EvansFoundTransDec2023.mp3
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Found in Translation

The Big Sleep

By: Jay Evans, USDA Beltsville Bee Lab

In most of the northern hemisphere, beekeepers have put their colonies to bed for the Winter and are eagerly anticipating their Spring awakening. Unfortunately, only two-thirds of colonies that go into Winter come out alive, leading to silent Springs for large and small beekeepers and impacting early pollination events. The only upside, for some, is a booming market for package bees and nucleus colonies. The causes of Winter losses are many, and determining which threats are most important is an active research topic.

This research takes three forms: 1) Direct experimental tests of potential killers, 2) Correlative studies of possible causes within and outside colonies and 3) for the extremely patient, long-term studies of Winter losses at the apiary or neighborhood level across different habitats. The ultimate goal of this research, and of beekeeper observations of their own losses, is to manage bees and their environment in healthier ways. A short-term goal, if less satisfying, is to simply have a better grasp of how many colonies will be on hand before making commitments to pollinate or placing early orders for new Spring bees.

Experimental manipulations of colonies followed by a wait-and-see for Spring are challenging and expensive. To date, these experiments have pointed towards Varroa mite treatment as the single most important, and largely doable, management step needed to improve Winter survival, with nutrition, queen health and pesticide exposure all playing roles. These small-scale experiments are mirrored by insights from the Bee Informed Partnership’s Colony Management survey (www.beeinformed.org). Beekeepers remain the single most valuable player in maintaining colony health.

What about neighborhood or landscape causes for Winter losses? With increased tools for hive-monitoring tools and vital governmental resources for mapping reported land uses (e.g., the USDA’s Cropscape program, https://nassgeodata.gmu.edu/CropScape/), predicting landscape forces that sustain or kill bee colonies has become highly useful. I have highlighted the ‘Beescape’ project before (www.beescape.org), an effort to show beekeepers what is within foraging distance of their colonies. With parallels in other parts of the world, Beescape can guide apiary placement and nutrition management, and is also simply fascinating in a ‘Zillow’ sort of way in showing the best neighborhoods for raising bees. Land-use maps have been used to assess landscape features that favor bee health in habitats ranging from the western bee ‘breadbaskets’ to Philadelphia. As an example of the former, Dan Dixon at the University of North Dakota and colleagues from the U.S. Geological Survey mapped land use changes surrounding known apiaries across eastern North Dakota in Land conversion and pesticide use degrade forage areas for honey bees in America’s beekeeping epicenter (2021; PLoS One; https://doi.org/10.1371/journal.pone.0251043). They used this information to develop a ‘Quality Index’ for apiary sites, noting where colonies were likely to be exposed to insecticides and other threats and where they would be less vulnerable to those threats. As expected, areas with more natural forage, including those managed through the USDA’s Conservation Reserve Program, presented healthier forage options within reach of resident beehives. This recent work mirrors prior work in the same region, showing the importance of healthy forage for honey bee survival and honey production (i.e., recent work led by Autumn Smart from the University of Nebraska with the USGS team, Landscape characterization of floral resources for pollinators in the Prairie Pothole Region of the United States, 2021, Biodiversity and Conservation 30:1991-2015, https://digitalcommons.unl.edu/entomologyfacpub/949).

Given the decent insights from experiments and landscape-level surveys, why would anyone wait on decades-long surveys to identify the causes of colony losses? First, these surveys are the best for showing changes in forage and climate over the long term. They also help separate threats beekeepers and bees can address from those they cannot. A brand-new 10-year survey from Germany points out some known risks while also finding a surprising twist. Jes Johannesen and colleagues, in Annual fluctuations in Winter colony losses of Apis mellifera L. are predicted by honey flow dynamics of the preceding year (2022, Insects 13, 829, https://doi.org/10.3390/insects13090829), merge hive monitoring and weather data with actual colony losses (as reported in surveys) to explore connections across years.

First, the authors make the case that management practices and bees are fairly homogenous, and hence variation in colony losses likely reflects climate or other environmental external variables. This is perhaps more true in Germany than in the U.S. Counter-intuitively, years in which bees started to return with forage sooner, i.e., ‘early Springs’, were linked with both larger colonies and heavier Winter losses the following Winter. This result likely reflects longer growing seasons for varroa mites and the delayed impacts of those mites. When ‘start date’ is factored out, colonies that gained weight the fastest in a three-month Spring flow had higher odds of surviving Winter, so colony growth itself remains a good predictor of colony futures. In a sign that local conditions are critical, colony losses in August correlated with losses the following Winter in the same apiaries. It would be nice to see disease data for these colonies; perhaps they had high virus, nosema or other loads that might have been a predictor of bad news by the following Spring, if not a trigger for disease control that Fall. The most surprising result involved year-to-year changes. Apiaries with low losses one year tended to have higher losses the next, and vice versa. Their best guess for a cause of this odd trend was that prior or alternate years might act as a purge for locally bad colonies, and the survivors would be, at least momentarily, over-achievers. Again, these surveys did not involve actual sampling, so it is hard to test that idea. I hope your own colonies fare well this Winter and are buzzing when you check them in 2023.

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Found in Translation https://www.beeculture.com/found-in-translation-31/ Tue, 01 Nov 2022 12:00:38 +0000 https://www.beeculture.com/?p=42953 https://www.beeculture.com/wp-content/uploads/2022/11/Evans_FoundTransBCNov2022.mp3
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Found in Translation

Climate Control

By: Jay Evans, USDA Beltsville Bee Lab

Honey bees control the temperature in the core of their colonies to a degree you can only dream of for your home. By humming muscles (burning sugary carbs) and ventilating, they stabilize both temperature and humidity across a wide range of outside conditions. How they do this and the causes of major shifts from normal hive conditions are topics of great interest for colony health. Running too hot in the Winter can stress the cells of bees, or at least reflect the wasteful use of honey. Running too cold also stresses bees, especially brood, and can put colonies at greater risk from parasites and pathogens (which tend to come from lineages that exploit less hot-blooded insects).

Beekeepers and scientists have developed and adopted numerous technologies for monitoring hive conditions. Superfans can find hours of videos by experts in this realm from the most recent International Bee and Hive Monitoring Conference, held at the University of Montana (https://www.youtube.com/playlist?list=PLK1L4YyuyoO1WxuH1Dg4sxhM-FOEDYhW_). Highly accurate thermocouples are inexpensive and depend on minimal energy. Similarly, monitors for humidity are readily available, as are monitors for sound. Slightly more complex probes can determine relative levels of oxygen or CO2 in the hive environment. All of these measurements can be reported out to the wider world via antennae aimed at cell phone towers or satellites, joining the cacophony of the ‘Internet of Things’.

Scientists using this technology receive unprecedented insights into how colony conditions, management and hive materials impact the bubble in which colonies live. In total, the results have some bearing on management and diagnoses of when things are going poorly. They also might change how you manage, feed and house your bees. The concept of indoor weather reports from beehives is not new, of course. Hive temperature values gathered by James Simpson for his 1961 paper Nest Climate Regulation in Honey Bee Colonies (https://www.science.org/doi/10.1126/science.133.3461.1327) are still accepted as truth for colonies in Winter and Summer and within and outside the cluster of bees. Namely, the cluster itself is HOT, and stable, fluctuating only slightly from 34oC (93oF). This cluster temperature trends lower and becomes a bit less stable in the absence of brood, but Winter bees from Texas to Toronto keep things amazingly hot and stable through the coldest Winter.

So how do beekeepers help their colonies control temperatures efficiently? I have written before about the resurgence in storing colonies in buffered buildings, or underground, during Winter as a means of decreasing stress and honey consumption. What about hive-centered fixes? Working from the outside in, what is it about the hive environment that helps honey bees regulate their inner selves? For any given climate, bees and beekeepers have some say about the building materials and integrity of colony homes. Some beekeepers feel that natural hive cavities and managed hive bodies that most closely match the ancestral homes of honey bees will lead to healthier bees. Groups such as Apis arborea (https://www.apisarborea.org) are leaning into this idea with naturalistic beekeeping. Others have focused on mass-produced and marketed options. My USDA colleagues Mohamed Alburaki and Miguel Corona have compared the well-used wooden Langstroth hive body to one of the available synthetic hive options. Using bee-free boxes and cold stretches of the Maryland Winter, they showed that synthetic boxes absorbed and maintained solar energy more effectively and (counter-intuitively to me) also kept the hive environment at lower humidity at a range of temperatures (Polyurethane honey bee hives provide better Winter insulation than wooden hives, 2022, open-access in Journal of Apicultural Research, https://doi.org/10.1080/00218839.2021.1999578). These are both desirable traits for a hive structure. Similarly, Daniel Cook and colleagues from Brisbane, Australia, showed in Thermal impacts of apicultural practice and products on the honey bee colony (2021, Journal of Economic Entomology, doi: 10.1093/jee/toab023) that polystyrene hives maintained heat far better than wooden hives, while also showing that stored honey, while costly to heat initially, acted as wonderful insulation for bees trying to keep warm. In prior work, Yasar Erdogran from Turkey did a similar study but with bee-filled colonies (Comparison of colony performances of honey bee (Apis mellifera L.) housed in hives made of different materials, 2019, in the obscure but accessible Italian Journal of Science, https://doi.org/10.1080/1828051X.2019.1604088). Here, polyurethane colonies had higher brood production and honey yields than wooden hives, but wooden hives with an exterior sandwich of insulation were significantly better than both, even during the Summer.

Other studies suggest that bees themselves, and their behaviors, are predominant in maintaining a cozy home. Using longterm and precise reporting of temperature and levels of CO2, William Meikle and colleagues showed how bees can make different houses work for them in Honey bee colonies maintain CO2 and temperature regimes in spite of change in hive ventilation characteristics, 2022, Apidologie, https://doi.org/ 10.1007/s13592-022-00954-1). Bees showed a narrow core temperature band in both standard hives and hives with a screen bottom board, and strong daily cycles in CO2. Colonies had higher CO2 levels when housed with screen bottom boards but this difference was not as large as the natural daily cycling of CO2. Dashing a good story, colonies did not show any sort of group-level ‘breathing,’ whereby gas levels changed on a cycle from seconds to hours. Building on the complexity and seasonal nature of all this, Ugoline Godeau and French colleagues monitored the temperatures of different parts of dozens of hives for two years (!), giving the best view yet of energy loss and heat production within bee homes. In their 2022 pre-print study Stability in numbers: a positive link between honey bee colony size and thermoregulatory efficiency around the brood (https://ecoevorxiv.org/9mwye/) they reinforce how remarkably stable hive temperatures remain, while showing minor changes with colony size, namely that worker bee population, and not brood numbers, per se, is positively tied to temperature stability. This is only true when brood is present and when probes are in areas containing brood. When brood is absent, as observed 60 years ago by Simpson, hive temperatures fluctuate madly.

So how can this information be used to improve beekeeping? It is evident that hive sensors can help determine optimal bee houses for any given climate, and perhaps these sensors will help beekeepers decide when and how to remove honey and swap out drawn frames for foundation with the least impact on the bubble their bees prefer. It is possible that multiple hive temperature sensors can tell beekeepers when brood is absent or retracting, but bees seem to be quite good at showing heat when even small patches of brood are present. Hive sensors that measure CO2 and other hive gases (oxygen, nitrogen, etc.) are more costly but give unique insights into bee activity, and perhaps the efficient use by bees of incoming energy. How these physical measures mesh with continuous monitoring of hive weight, and sound for that matter, remains to be seen. For now, for most of us, we can get general insights from studies that use accurate and constant probes, but our most useful insights (and satisfaction) will come from lifting hive covers.

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Found in Translation https://www.beeculture.com/found-in-translation-30/ Sat, 01 Oct 2022 12:00:45 +0000 https://www.beeculture.com/?p=42651 https://www.beeculture.com/wp-content/uploads/2000/01/EvansBC_FoundTransOct2022.mp3
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Found in Translation

I’ve just gotta bee me!

By: Jay Evans, USDA Beltsville Bee Lab

Picture peeping into an observation hive or simply watching a pulled frame of calm worker bees. You will soon notice a range of different acts by the bees in your view. Some might be burrowed into cells, some will be engaged in intimate conversations with nestmates, some will be carrying hive debris and some will be doing a happy dance after bringing back pollen or nectar. It has been known for decades that worker bees advance through different tasks as they mature. The primary shift is from ‘nursing’ or nest behaviors while bees are young, to foraging behaviors as they grow older. Young bees produce a nutritious processed food that they use to provision brood, and younger bees also produce the wax needed for hive partitions. Older bees, typically around two weeks old, start a life of foraging when outside conditions permit. If you want to read more about life’s big changes among social insect workers, including this switch from indoor to outdoor tasks, read the review article Regulation Of Division Of Labor In Insect Societies by Professor Gene Robinson (https://www.researchgate.net/profile/Gene-Robinson/publication/21615667_Regulation_Of_Division_Of_Labor_In_Insect_Societies/links/5738cf9a08ae9f741b2bd8a1/Regulation-Of-Division-Of-Labor-In-Insect-Societies.pdf), a review which has held up well since being published 30 years ago.

But these major transitions are not the whole story. Gazing into our lab’s observation hive makes me think of the picture books by Richard Scarry I read while young (you can’t go wrong with his book What do people do all day?). In these books, everyone is shown doing a specific trade, reflecting the many workers needed to make societies function. Bees are onto that as well, by specializing to some extent on certain hive roles. The specialization is subtle in the face of typical life transitions. Most bees, if they live long enough, will fly from the hive as they mature and initiate foraging. Similarly, most young bees will do some nursing. But there are deviations from this path. Some bees are known to be ‘precocious’ foragers, perhaps reflecting a stress faced earlier in their lives or perhaps reflecting their particular genetics. While foraging, some bees might prefer pollen to nectar on their floral trips, while others might tend to favor resins from plants, or water. In the nest, some bees are better linked into the social web than others and some might linger on particular observable tasks. In short, a bee is a bee; a replaceable but non-identical part of the whole colony.

Recent technical advances allow researchers to both measure and analyze the behaviors of bees throughout their lifespans and in a social setting. Numbered tags, similar to those put on some queens, have been used to keep track of individual worker bees for decades. Newer tags are both more ‘apparent’ to hive sensors and have a far greater level of discrimination, allowing hundreds or thousands of bees to be followed at once. Professor Robinson’s group has deployed this technology to tackle bee health issues ranging from the impacts of infection and chemical stress on bee behavior to a better understanding of the underlying neurodiversity of bees and how this diversity is driven by age and genetics. One example of this line of work comes from a paper with Tim Gernat as lead author (Gernat T, Rao VD, Middendorf M, Dankowicz H, Goldenfeld N, Robinson GE (2018) Automated monitoring of behavior reveals bursty interaction patterns and rapid spreading dynamics in honeybee social networks Proc Natl Acad Sci 115:1433–1438. doi:10.1073/pnas.1713568115). My favorite insight from this paper was that bees did not inherently recognize each other as individuals, and therefore bee-to-bee feeding was driven by chance encounters and immediate cues, rather than some shared memory of prior encounters. The paper is highly technical, in part because the authors want the results to be general to all society interactions, including our own. It is also impossible to analyze so many interactions without classifying each encounter in a strict mathematical way.

If that paper catches your interest, you will also enjoy an upcoming paper that tackles individual bee biases (‘personality’ is probably too strong of a word) that can last throughout their lifetimes. This paper, led by Michael Smith from Auburn University (Smith, M. L., Davidson, J. D., Wild, B., Dormagen, D. M., Landgraf, T., & Couzin, I. D. (2022) Behavioral variation across the days and lives of honey bees. iScience, 104842. https://doi.org/10.1016/j.isci.2022.104842) ups the bee-tracking challenge by following over 4,000 nestmates as they do their nest duties over an entire Summer. The results are complex and could be scrutinized for months, but there are some interesting guilds or ‘clusters’ of bees that seem to be on more similar paths than the paths of others. These paths involve the aforementioned age-biased tendencies to leave the nest and fly. Within that split, some groups of bees might be more prone to navigate widely in the nest than others, or to be found hovering around honey stores. And I especially resonated with ‘day cluster 4’ (“behavioral days associated with middle-aged bees, with metrics representing slow, localized behavior”). That sounds a lot like the past two years for me.

When one looks at the ‘lifetime achievement’ of individual bees, there are bees that moved to foraging earlier than others (and died younger) but also bees that tended to be more mobile in the nest, and show traits that set them apart from other nestmate groups. In short, whether defined by five clusters (as in this study for bee-days and bee-lives) or three or 20 clusters, there is solid evidence that bees don’t all follow the same life journey. It will be fascinating to connect these behavioral quirks with bee genetics (reflecting the dozens of possible paternal lineages in each colony), pesticide exposure, or maybe just a chance encounter of some sort earlier in life that has long-term impacts on bee lives. Honey bees have faced a lot of scrutiny by beekeepers and scientists, but one of the last frontiers is to see how individual members of the colony superorganism deviate enough from the lockstep of colony life to make things perhaps a bit more stable, if not more efficient. It takes a colony to raise a bee, but that bee then has some flexibility in her choices as she navigates cues and events both within and outside her home.

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Found in Translation https://www.beeculture.com/found-in-translation-29/ Mon, 13 Jun 2022 13:00:24 +0000 https://www.beeculture.com/?p=41802 Protein Sources and Colony Growth
By: Jay Evans

Hopefully those in the Northern hemisphere have your bees situated so they are taking advantage of this month’s bounty of flowers. Bees have evolved with, and driven the evolution of, flowers and honey bees and generally know when and how to harvest the good stuff those flowers produce. In ideal conditions your bees are surrounded by diverse, untainted flowers and resources. This is especially important thanks to the many components of natural pollen, which provides not just body-building protein but bee requirements from plant chemicals to fatty acids and micronutrients. A recent openly available review from Maciej Sylwester Bryś and colleagues in Poland (“Pollen Diet—Properties and Impact on a Bee Colony”, 2022, Insects, https://doi.org/10.3390/insects12090798) hits the key points in the search for beneficial pollens. They end with, “While single species pollen has specific benefits, bees require pollen from diverse sources to maintain a healthy physiology and hive. Multipollen diet should be offered to the bees to derive requisite benefits and at the same time be secure of the colony requirements.” These pollen sources might be gathered over time as new plant species come into flower and others fade, leading to a mixed cupboard in the hive. While I do not know of evidence for this, it would be nice to know if bees, like us humans, draw from different parts of this cupboard for each ‘meal’, to make sure they are getting a range of diversity for their own needs and those of their offspring.

But what happens if your bees aren’t lucky enough to live in a utopia of diverse flowers, or have not been able to store sufficient pollen when that window was open. Also, most of us live in highly seasonal climates and there is often a desire to supplement our bees either for our needs (i.e., fast growth for splits as well as larger workforces for pollination contracts or honey gathering) or the bees’ needs (perhaps when bad weather or post-Winter weakness might conspire to make colonies miss key flowering events altogether).

Three recent papers tackle some of the current options available to beekeepers to give their colonies a boost, via natural pollen supplements or other sources of nutrients. I have no interest in recommending particular products, but appreciated the research insights into how honey bees convert specific supplements into new, healthy offspring. Shelley Hoover and colleagues in Alberta describe a three-year field study of bee feed supplements in their study “Consumption of Supplemental Spring Protein Feeds by Western Honey Bee (Hymenoptera: Apidae) Colonies: Effects on Colony Growth and Pollination Potential” (2022, Journal of Economic Entomology, https://doi.org/10.1093/jee/toac006). They gathered and scored colonies immediately after Winter storage and fed them feeds containing pollen or alternate protein sources (versions of Bee Pollen-Ate, FeedBee, Global Patty and Healthy Bees). With or without pollen, the feed supplements had protein ratios similar to natural pollen and many of the other diet needs reflected in pollen, albeit with shifts in relative amino acid abundance. All supplements were consumed readily, although FeedBee was taken at slightly lower rates. Interestingly, a ‘Trio’ of three protein supplements that perhaps better mimics a multifloral resource was consumed preferentially to single-type diets, to the tune of over 1,792 grams in five weeks versus the next-favored patty (Global Patty 15%, 1,379 grams). In the end, these consumption rates did not necessarily predict impacts on colony health and all diets were palatable. Here, the tested supplements indeed showed their worth relative to control colonies fed only sugar. The pollen-based diets did better across the three years than others, under local conditions, indicating they can provide bees an early season boost over natural forage, as advertised.

Vincent Ricigliano and colleagues carried out a feed supplement trial across the dearth season of a U.S. commercial beekeeping operation, a key consumer group for bees and agriculture (“Effects of different artificial diets on commercial honey bee colony performance, health biomarkers, and gut microbiota” BMC Veterinary Research (2022) 18:52; https://doi.org/10.1186/s12917-022-03151-5). These trials started with 144 equivalent Californian colonies which were provided supplemental patties starting in August for a total of 12 times over the course of the subsequent months. The goal was to see how treated and supplemented colonies looked prior to the next year’s almond pollination event, in apiaries not blessed with great natural forage over the measured time period. Two of the tested supplements held natural pollen (Global and ‘Homebrew’) while the rest used alternate protein sources (Ultra Bee, Bulk Soft, MegaBee™, AP23, and Healthy Bees™). All supplements had protein ratios within range of natural pollens (15-20%). Nevertheless, they differed significantly from natural pollen and from each other in key components including the ratios of specific essential amino acids and lipid levels. All diets were consumed equally well at the first feedings, although some were eaten less readily as the experiment continued. Six months later, in preparation for almond pollination, there were strong differences in colony strength based both on which of three apiary locations a colony had been placed into and the supplemental diet provided. While the apiary differences highlight the complexities of working with field colonies, the diet results give insights into the effectiveness of specific supplements in at least one part of the world.

Emily Noordyke and colleagues focused on the effects of late-season protein supplementation on colony survival in part of a mild Florida Winter (“Evaluating the strength of western honey bee (Apis mellifera L.) colonies fed pollen substitutes over Winter,” 2021: Journal of Applied Entomology; DOI: 10.1111/jen.12957. Experiments were started in November with supplementation via two commercial protein supplements (Api23 or Megabee) compared to a non-supplemented control set of colonies. Experimental colonies faced an environment with diminished natural pollen and were further stressed by pollen traps. Both supplements led to stronger colonies (less weight loss) than those not receiving supplements, although the results were only significant for Api23. Brood mass was higher in both supplemental cohorts than in the controls.

These colony-level and season-relevant experiments show the benefits of protein supplements in times of dearth. For now, your bees are hopefully getting the bounty of great flowers and are building for splits and healthy long-lived foragers now and into the Fall.

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Found in Translation https://www.beeculture.com/found-in-translation-28/ Mon, 23 May 2022 13:00:43 +0000 https://www.beeculture.com/?p=41148 Bees and the Web that Traps Them
By: Jay Evans, USDA Beltsville Bee Lab

While big injuries, exposures and accidents are always a risk, it is more often an accumulation of small insults and decay that bring down honey bee colonies. Baffled by not being able to find a singular cause for Colony Collapse Disorder, we coined ‘pathogen webs’ ten years ago to describe what was actually seen in collapsed colonies (Robert Cornman and colleagues, Pathogen Webs in Collapsing Honey Bee Colonies, 2012, PLoS One, https://doi.org/10.1371/journal.pone.0043562). Troubled bees contained multitudes of microbes, but those multitudes were different from Bakersfield to Okeechobee and from Harrisburg to central Texas. We might have missed the forest for the trees, as I mused for Bee Culture in C-C-Decade, (2018, https://www.beeculture.com/found-in-translation-13/) but perhaps the multitudes would have given us better insights if we had just waited long enough.

Dr. Renata Borba, from Agriculture & Agri-Food Canada’s Beaverlodge Research Farm (and now with the Alberta Beekeepers Commission), led her Canadian colleagues in a tremendous project to identify web players and ultimately connect them with poor colony health. Their open-access study, Phenomic analysis of the honey bee pathogen-web and its dynamics on colony productivity, health and social immunity behaviors, (2022, PLoS One, https://doi.org/10.1371/journal.pone.0263273), one-ups, or rather three-ups, prior work. 1) They sampled far more extensively both at each sample point (hundreds of bees) and across the country, 2) they looked at other key colony traits, from behaviors to honey yield, and 3) they checked up on their patients, gleaning data from one season to the next, important for assessing what really matters in sustainable beekeeping.

With over 1500 bee colonies, mostly started from packages, they had many opportunities to see how bee traits, management, and bad luck could lead to colony losses and honey production. You should read and discuss the paper to get more of their insights, but here are a few that stood out.

First, hygienic behavior really works: Colonies that scored high for a freeze-killed brood assay or for signs of grooming (in the form of mangled mites on the bottom board or in the sheer number of mites dropping over three days) showed lower mite growth rates, lower virus levels, and generally fared better. In fact, in the first year of the study, when 1000 colonies were vetted, 14/16 negative traits, from virus loads to mite numbers in multiple seasons, decreased significantly as hygiene scores (freeze-killed brood assay) increased, and the other two traits were non-significant but trending negative. The two other signals of grooming were not significantly tied to as many traits, although this might reflect the difficulty in quantifying these traits more than their importance as a form of social defenses against mites. In fact, in the second year the grooming ‘mite-damage’ score was a better correlate with decreased disease risk. This is comforting news and rare data for the colony level.

The study also quantified the importance of mite control on bee health. Mite numbers (as measured by alcohol washes) were positively tied to viral and nosema disease, and negatively tied to cluster size at both the time of measurement and the start of the next Spring. Several mite-transmitted viruses also showed predictive value for the state of colonies in current as well as subsequent seasons. Since there are not yet direct controls for viruses, the authors recommend effective mite controls coupled with selection for hygienic traits as the best way to decrease this threat. Interestingly, ‘total mite count’ in colonies was positively tied to sealed brood, in large part because of the ample mites found reproducing in sealed brood. This measurement was made by longterm exposure of colonies to amitraz while collecting fallen mites via sticky boards and is not normalized by the net amount of bees or brood. Results showing that mite control improve colony odds are not new, but the consistency of this work across Canada when compared to longterm studies in the U.S. and Europe suggests that Varroa and its viral partners remain the biggest drain on honey bees in most places. Another 2022 study, by Julie Hernandez and colleagues in Switzerland, showed 25-fold higher colony survival rates when beekeepers followed recommended mite treatments (Compliance with recommended Varroa destructor treatment regimens improves the survival of honey bee colonies over Winter, 2022, Research in Veterinary Science, https://doi.org/10.1016/j.rvsc.2021.12.025). The Borba study from Canada gives hope that some of the treatment burden, at least, can be reduced via good genetics.

Borba and colleagues refine additional yardsticks beekeepers might use to predict colony health and treatment regimes. While the results are confined to the eight populations studied, the authors argue that Spring colony weight is a poor predictor of current or future health, in large part because of greater honey stores in declining or lost colonies when compared to colonies that were ready to really take off. This is most evident in the first Spring cohort. Conversely, Fall colony weight does seem to predict disease load and, by correlation, colony health status in the Spring. Worker bee cluster size was a robust predictor of mite and disease status in both fall and spring, and this measurement is preferred.

The authors will report separately on the impacts of different management schemes (mite regulation and indoor versus outdoor storage) that varied across beeyards in this immense experiment. Integrating genes, behaviors (human and bee) and climate across a wide country is sure to give helpful insights for beekeepers everywhere, so keep an eye out for that study. In the meantime, mind the web and beat the mites.

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Found in Translation https://www.beeculture.com/found-in-translation-27/ Mon, 04 Apr 2022 13:00:14 +0000 https://www.beeculture.com/?p=40907 Highlight Film: American Association of Professional Apiculturists
By: Jay Evans, USDA Beltsville Bee Lab

Having honed my endurance by watching dozens of Winter Olympic events (who knew curling was so TV-friendly and intense?), this month I am ready to tackle not a couple but 17 new works: specifically, a compilation by members of the American Association of Professional Apiculturists (comprised of Apiary Inspectors, researchers and educators who work with honey bees, along with a few passionate beekeepers, https://aapa.cyberbee.net/). The AAPA joins one of the two major national bee industry meetings each year via their American Bee Research Conference (the results of which have been presented in Bee Culture this month and last) and every few years officers of the AAPA collect and edit a series of peer-reviewed papers from our field. This time, Drs. Michael Simone-Finstrom (USDA-ARS), Hongmei Li-Byarlay (Central State University) and Margarita M. López-Uribe (Penn State University) edited papers for two rounds in the freely available Journal of Insect Science (https://academic.oup.com/jinsectscience/issue/21/6 and https://academic.oup.com/jinsectscience/issue/22/1). This Special Collection “Honey Bee Research in the United States: Investigating Fundamental and Applied Aspects of Honey Bee Biology” truly has something for everyone.

For those interested in bee disease, four works tackle Varroa mites. Bee Culture writer and scientist Jennifer Berry and colleagues from the University of Georgia and Auburn University show the good and the bad of repeated mid-season oxalic acid treatments (in this case by vaporization; https://doi.org/10.1093/jisesa/ieab089). Quite ambitiously, they treated colonies every five days, seven times in a row, in the middle of Georgia and Alabama Summers. This held mite levels in check in treated colonies while, in two of three years, untreated colonies showed the predicted seasonal mite increases. Overall, the ‘percent mite intensity’ (mite counts per 100 bees) differed by five mites in treated versus untreated colonies, almost entirely due to increases in the latter. Colonies themselves survived the aggressive treatment regime fine and in one trial the treated colonies showed a trend toward having more food stores. No word yet on how colonies with diminished mites fared during late-season and Winter challenges.

Cameron Jack and Jamie Ellis (University of Florida) reviewed the available integrated pest management (IPM) strategies for Varroa in the U.S. (https://doi.org/10.1093/jisesa/ieab058). They started by defining the mite levels that result in unacceptable injury and economic damage to honey bees and beekeepers, respectively. Prior to that are thresholds for management action. In general, the ethic of IPM is to avoid risk altogether by breeding or isolation, monitor often, and then apply gradually more and more aggressive control methods when mite impacts are imminent. The authors covered the latest recommendations on mite counts, available controls, and vailable bee stock that might help delate or avert escalation.

Kate Ihle and USDA-ARS colleagues tackled a potential form of mite resistance to Varroa. They label social apoptosis, namely a tendency for parasitized brood to give up and die when capped, perhaps sealing the fate of their mite parasites (https://doi.org/10.1093/jisesa/ieab087). They found some differences in this tendency across different bee lines and also a striking effect of the colony environment. By rearing brood from egg to sealed brood in common colonies, they showed that bees raised in colonies with high mite loads tended to die at higher rates.

Finally, Taylor Reams and Juliana Rangel review the state of knowledge for mite genetics and behavior (https://doi.org/10.1093/jisesa/ieab101). To explore diagnostic tools for European foulbrood, Meghan Milbrath and colleagues at Michigan State University and USDA-ARS (including myself) pitted three diagnostics based on microscopy, genetics, and a commercial antibody test against each other (https://doi.org/10.1093/jisesa/ieab075). For 77 cases of true EFB, and nearly 400 larvae, all three methods behaved similarly.

Several authors focused on the stresses faced by bees in managed farmlands. Dylan Ricke and colleagues from the Ohio State University measured the effects of agrochemicals on honey bee queen development (https://doi.org/10.1093/jisesa/ieab074). The insect growth regulator diflubenzuron was especially damaging, reducing queen survival to adulthood by more than 80% when presented in pollen at field-relevant levels. This paper also provides critical data for the persistence of chemicals and adjuvants from pollen to royal jelly to developing bees.

Bradley Ohlinger and colleagues at Virginia Tech University looked at the impacts of sugar syrup laced with 26 parts per billion of imidacloprid on foraging and recruiting (https://doi.org/10.1093/jisesa/ieab095). Foraging trips decreased by a third, a significant result, while there were trends toward reduced dancing by returning bees to direct their sisters to food.

Arathi Sehadri and Elisa Bernklau (USDA-ARS) found that plant chemicals found in nectar and pollen can interact with a common insecticide, thiamethoxam, to either increase or decrease risk to honey bees, depending on conditions (https://doi.org/10.1093/jisesa/ieab053). Michael Simone-Finstrom and colleagues described the impacts of local bee colony transport on stress genes and disease agents in bees (https://doi.org/10.1093/jisesa/ieab096). These are hard experiments because bees on the move face different foods than those left behind. Here, through a clever use of bee-swapping after migration they were able to decouple in-move stress versus lasting effects and did see some minor changes in pathogens for both. As someone who has puzzled for years over the web of microbes in bees and their importance, this paper also offers a strong look at how microbes and bee traits like immunity relate to each other. To add layers to that complexity, in a provocative but hard read for many of us, Maggie Shanahan from the University of Minnesota presents the case that we are missing the forest for the trees (https://doi.org/10.1093/jisesa/ieab090). With some tough-love for both researchers and the beekeepers we support and respect, she argues for a major upheaval of current practices. She is an excellent writer and this essay provides food for thought and thought for food.

No compendium of bee science is complete without some love for reproduction and this batch has several papers on this topic. Sarah Lange and colleagues from Louisiana State University and USDA-ARS shed light on how treating or ‘priming’ a queen might lead to better immunity for her thousands of offspring (https://doi.org/10.1093/jisesa/ieac001). I described some early evidence for this in Bee Culture in 2017 (https://www.beeculture.com/found-in-translation-3/) and it remains a hot topic today. By carefully exposing queens to a virus either through oral exposure or through the fluids used in instrumental insemination, Lang and colleagues found evidence in one trial that consequent offspring (from nine queens treated via insemination fluids) were indeed less prone to virus infection. Regrettably, in round two of the same experiment ‘primed’ queens produced MORE vulnerable offspring. In both cases the results, yeah or nay, were significant, suggesting that bee genetics or underlying infections affect the outcome…not quite ready for prime time but exciting nonetheless.

Also exciting are new ways for bee breeders to improve their selection routines. Kaira Wagoner from the University of North Carolina-Greensboro, with longtime leaders in bee behavior and hygienics, described a brand-new assay for identifying hygienic stock (https://doi.org/10.1093/jisesa/ieab064). Using a cocktail of smells released by stressed bee larvae, they vetted colonies for the tendencies of worker bees to identify and clean out parasitized sisters. The assay, based on ‘Unhealthy Brood Odor’ (UBO), held up well against the freeze-killed brood assay, is safer for humans, and relies on only a tiny circle of brood. Stay tuned as Dr. Wagoner and team develop this into a package breeders can acquire and use. For now, just remember that if UBO, then UBD (you be dead).

Bradley Metz and colleagues from North Carolina State University and Mississippi State University present an analysis showing exactly how nurse bees react to these types of smells (https://doi.org/10.1093/jisesa/ieab085). With significantly less stress (being blocked from receiving food for four hours), developing larvae were able to attract a larger crowd of attendant workers during the next hour. The researchers did not quite succeed at isolating this ‘HBO’ (‘Hungry Bee Odor’) at the chemistry level, but the result alone suggests a volatile or surface mix of chemicals does bring a helpful response. They also found that hunger cues isolated from deprived larvae can lead to greater pollen foraging at the colony level, a result with great practical and biological implications.

Males (drones) were not ignored in these articles, starting with a demonstration of the physiological stages of drone bee sex parts as they mature by Colby Klein and colleagues from the University of Saskatchewan, Canada (https://doi.org/10.1093/jisesa/ieab064). Along with confirming that drones take longer to mature in cooler Spring temperatures (a four-day difference between June and July), this paper gives a day-by-day ‘expected’ state for drone testes. This roadmap can be used in future studies aimed at the many biological, temperature, and chemical stresses that impact fragile males.

Next, Bradley Metz and David Tarpy from North Carolina State University gave an overview of drone quality for U.S. bees (https://doi.org/10.1093/jisesa/ieab048). They first generated a useful metric for good males by contrasting many measurements for drones reared in drone cells with those reared, atypically, in worker cells. As expected, drones reared in the right places looked better and performed better. This separation fed into statistics for what a healthy drone SHOULD look like when emerging from a drone cell. 2% of such drones actually fell into the worker-cell category, while 17% orfworker-cell drones came out ready to battle equally with drones reared in drone cells. They also compared drone quality across 19 operations and found substantial variation. As with their excellent work on queen quality, these tests were not designed to shame specific breeders but perhaps to guide them in ways to do better.

In another attempt to understand how genetic and environmental backgrounds favor survival in bees, Kilea Ward and colleagues from Central State University measured longevity of foraging worker bees plucked from traditional and feral colonies (https://doi.org/10.1093/jisesa/ieac002). Bees from feral colonies survived significantly longer when held in an incubator, while also showing more signs of oxidative stress. How they were able to tolerate that stress remains an open question.

Finally, for fascinating natural history, you should read Willard Robinson’s story of the most bird-like bee, Apis dorsata, a species that moves miles and miles as a colony across the seasons, and in search of forage (https://doi.org/10.1093/jisesa/ieab037). These colonies move over 100 miles, apparently to the same spots, and he discusses the conundrum of who drives the return when surely most, if not all, workers die between migrations.

These papers reflect the passions of researchers to better understand our favorite insect and to use science to improve their survival. Reading these great works at once felt like doing a 17-stage beeathlon, so it’s back to curling on the couch for now.

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