Honey Bees on the Mind

ROSEMARY BUSH BLOOMING, buzzing with bees and birds, a reminder of controversies swirling around pollinators and beneficial insect species. The past Entomological Society of America (ESA) annual meeting featured outstanding virtual presentations on honey bees, bumble bees and pesticides with diverse lethal and sub-lethal effects on fertility, learning, memory, etc. A mindless rush to ban neonicotinoids (neonics, a class of pesticides developed originally in Japan to minimize deleterious effects on beneficial insects like honey bees) has resulted in increased use of worse pesticides (some capable of completely wiping out bee populations). Partly to blame are acutely dysfunctional Tier 1-3 regulatory processes hidden deep in the bureaucratic bowels of the EPA.

University of Texas, Austin researchers are among those leading the charge to have the EPA evaluate sub-lethal effects of all pesticides being considered as neo-nic replacements. Not just on honey bees, but also on bumble bees and other non-Apis native bees (includes lesser-known, less-social squash bees, that are important crop pollinators). Using field-realistic micro-colony experiments with bumble bees, Leeah Richardson found chronic, dose-dependent effects from flupyradifurone, a popular neo-nic replacement: At high concentrations, despite normal birth numbers, all bee larvae were dead by the third instar. In other words, normal numbers of bumble bee larvae were being born, but survival to adulthood was zero. But because adult bees survive flupyradifurone sprays, the pesticide is approved for use on open flowers. Thus, EPA policy (whether inadvertent, incompetent or otherwise dysfunctional seems to favor pollinator abortions before adulthood). Pollinator population control surely is not the goal? Perhaps to regulate otherwise would allow accusations of being pro-life, even if it means stopping abortion of pre-adult honey bees?

Regulatory bureaucracies typically have 3 tiers for evaluating agro-chemicals. Tier 1 is lab experiments with the active ingredient to determine the LD50 (lethal dose to kill 50% of the population). Tier 2 is semi-field experiments (e.g. field cages with treated and untreated flowers for comparisons and evaluation of sub-lethal effects). Tier 3 field trials are very rare, only conducted when Tier 1 and Tier 2 data are inconclusive. “Sub-lethal assessments on native bees, bumble bees, solitary bees really need to be carried out in the regulatory process in Tier 1 as a mandatory requirement,” said UT Austin’s Harry Siviter, who found no advantage from neo-nic replacements such as sulfoxaflor. “Otherwise we are just replacing one insecticide with others that have similar effects.” In other words, choosing winners and losers in the agro-chemical marketplace in an almost arbitrary, nonsensical manner. Welcome to Alice in EPA Land.

Lars Chitka’s new book, The Mind of a Bee (Princeton Univ Press, 2022), is stranger in some ways than Lewis Carroll’s Alice’s Adventures in Wonderland. “Understanding the minds of alien life-forms is not easy, but if you relish the challenge, you don’t have to travel to outer space to find it,” writes Chitka. “Alien minds are right here, all around you. You won’t necessarily find them in large-brained mammals—whose psychology is sometimes studied for the sole purpose of finding human-ness in slightly modified form. With insects such as bees, there is no such temptation: neither the societies of bees nor their individual psychology are remotely like those of humans. Indeed, their perceptual world is so distinct from ours, governed by completely different sense organs, and their lives are ruled by such different priorities, that they might be accurately regarded as aliens from inner space. Insect societies may look to us like smoothly oiled machines in which the individual plays the part of a mindless cog, but a superficial alien observer might come to the same conclusion about a human society. “

“Each individual bee has a mind,” writes Chitka. “That it has an awareness of the world around it and of its own knowledge, including autobiographical memories; an appreciation of the outcomes of its own actions; and the capacity for basic emotions and intelligence—key ingredients of a mind. And these minds are supported by beautifully elaborate brains. As we will see, insect brains are anything but simple. Compared to a human brain with its 86 billion nerve cells, a bee’s brain may have only about a million. But each one of these cells has a finely branched structure that in complexity may resemble a full-grown oak tree. Each nerve cell can make connections with 10,000 other ones—hence there may be more than a billion such connection points in a bee brain—and each of these connections is at least potentially plastic, alterable by individual experience. These elegantly miniaturized brains are much more than input-output devices; they are biological prediction machines, exploring possibilities. And they are spontaneously active in the absence of any stimulation, even during the night.”

“To explore what might be inside the mind of a bee, it is helpful to take a first-person bee perspective, and consider which aspects of the world would matter to you, and how,” writes Chitka. “I invite you to picture what it’s like to be a bee. To start, imagine you have an exoskeleton—like a knight’s armor. However, there isn’t any skin underneath: your muscles are directly attached to the armor. You’re all hard shell, soft core. You also have an inbuilt chemical weapon, designed as an injection needle that can kill any animal your size and be extremely painful to animals a thousand times your size—but using it may be the last thing you do, since it can kill you, too. Now imagine what the world looks like from inside the cockpit of a bee. You have 300 degree vision, and your eyes process information faster than any human’s. All your nutrition comes from flowers, each of which provides only a tiny meal, so you often have to travel many miles to and between flowers—and you’re up against thousands of competitors to harvest the goodies. The range of colors you can see is broader than a human’s and includes ultraviolet light, as well as sensitivity for the direction in which light waves oscillate. You have sensory superpowers, such as a magnetic compass. You have protrusions on your head, as long as an arm, which can taste, smell, hear, and sense electric fields. And you can fly.”

Honey bee research has been a source of inspiration and innovation, and many cite Karl von Frisch, celebrated for his research on bee dances as a form of communication. Von Frisch shared The Nobel Prize in Physiology or Medicine 1973 with Konrad Lorenz and Nikolaas Tinbergen “for their discoveries concerning organization and elicitation of individual and social behaviour patterns”. Thomas D. Seeley of Cornell University writes in the 2022 Annual Review of Entomology: “In the 1920s, Karl von Frisch described a forager producing this dance as follows: “[she makes] trembling movements forward and backward, and right and left”. The meaning of this strange behavior remained a mystery to von Frisch for more than 50 years, and near the end of his career he wrote, “I think it tells the other bees nothing. . .and perhaps is comparable to the condition that Florey has described as a neurosis”.

“I solved this mystery in the early 1990s when I discovered that a nectar forager produces a tremble dance when she visits a rich nectar source but then, upon returning home, has difficulty finding a bee willing to receive her nectar load,” writes Seeley. “The tremble dance calls bees to work as nectar receivers at the start of a nectar flow, just like the whistle atop a sardine factory in Maine calls villagers to work as sardine packers when fishing boats arrive laden with herring. It was thrilling to discover the meaning of this dance. Martin Lindauer once told me that Karl von Frisch had said that he would award a prize to whoever deciphered the message of the tremble dance. Alas, he died in 1982, nine years before I solved this puzzle. My studies of how a honey bee colony nimbly and wisely allocates its foragers among flower patches, despite never-ending changes in the locations of the richest ones, did lead to a different prize some years later. This bee work inspired two computer scientists at Georgia Tech to create the Honey Bee Algorithm (HBA). The HBA is widely used in internet hosting centers (analogous to hives) to optimally allocate webservers (analogous to foragers) among jobs (analogous to flower patches), so it is integral to the multi-billion-dollar industry of cloud computing. In 2016, the American Association for the Advancement of Science awarded me and four professors of engineering at Georgia Tech—John J. Bartholdi, Sunil Nakrani, Craig Tovey, and John Vande Vate—its Golden Goose Award. This award recognizes esoteric research that proves extremely valuable (i.e., that lays lots of “golden eggs”).”

In the German to English translation of his 1953 book, The Dancing Bees, Von Frisch wrote: “SUPPOSE German and English bees were living together in the same hive, and one of the Germans found a lot of nectar: its English companions would easily understand what it had to say about the distance and direction of the find…If we use excessively elaborate apparatus to examine simple natural phenomena Nature herself may escape us. This is what happened some forty-five years ago when a distinguished scientist, studying the colour sense of animals in his laboratory, arrived at the definite and apparently well-established conclusion that bees were colour-blind. It was this occasion which first caused me to embark on a close study of their way of life; for once one got to know, through work in the field, something about the reaction of bees to the brilliant colour of flowers, it was easier to believe that a scientist had come to a false conclusion than that nature had made an absurd mistake. Since that time I have been constantly drawn back to the world of the bees and ever captivated anew. I have to thank them for hours of the purest joy of discovery, parsimoniously granted, I admit, between days and weeks of despair and fruitless effort.”

As has been demonstrated time and time again, nothing is ever conclusively established and beyond challenge in science. Though for periods of time beliefs get set in stone until demolished (1,500 years in the case of some of Aristotle’s nature observations). In the 1920s and 1930s, Nobel Prize-winning immunologists and the American Medical Association doubted the existence of phages (viruses that kill bacteria) and prohibited research on the subject, until finally proven wrong with the invention of the electron microscope. Perhaps it will be the same with the much-contested CO2 climate change hypothesis, currently enthroned on a golden pedestal and considered beyond discussion. Change is a constant, as Adrian Horridge documents in his history of insect vision.

In his book, The Discovery of a Visual System: The Honeybee (CABI, 2019), Adrian Horridge, a honeybee researcher in the UK and Australia since at least 1945, puts forth his controversial history of honeybee visual research. “Beside this saga of contending personalities, this is in fact a serious book that attacks the detail and gist of the compound eye of a typical day-flying insect…The topic of this book is the much-needed revision that puts insect vision as exemplified by the bee, and dim-light vision in other insects, back on track. The new paradigm for visual inputs of the compound eye is one tonic colour blue and two derivatives that are rates of change in blue and green receptor channels. I hope that the novel prospect will be of interest to engineers of robot vision…There is universal inertia against innovation because it is expensive and requires thought, hard work and persistence, and then disrupts set ways. Forces for conformity are now a universal and growing danger that should be resisted. But worst of all, innovation implies an escape from bureaucratic control.” Indeed, insect optics research applied to fiber optics helps enable the World Wide Web and Internet to link computers worldwide at near the speed of light -a major global disruption of social patterns and cultures.

“Already, two major innovations of practical importance have emerged directly from our studies of insect vision,” writes Horridge. “In 1972, from the optics of fly eye, Allan Snyder discovered how the light gets into the light guides. The details were copied into the design of the fibres that carry light pulses for extreme distances in the World Wide Web (Chapter 4). In 1989, Srinivasan, Lehrer, Zhang and I discovered that insects detect a panorama of range by signals created by their own motion, not of objects, and Srinivasan later completed the installation of the resulting applications into mobile vehicles that fly with a computer on board (Chapter 9). The future will bring another important development: reverse engineering of insect vision, simply because insects are examples of extremely sophisticated and well-adapted visual mechanisms at exactly the right level of complexity to be copied into silicon for practical applications, quite unlike our own vision. Moreover, many neurons in an insect, perhaps all, are individually identifiable, and the wiring diagram is also constant, so that we can repeatedly return to precisely the same circuit, neuron or synaptic connection, with a variety of different techniques.”

“As yet, we have no firm circuitry or formal connections in the bee beyond cues and their coincidences,” writes Horridge. “The ways that preferences are established, modified and remembered remain a mystery. We have no idea how bees reach decisions. We have not identified the points where the layout of the two-dimensional image on the eye disappears into responses of line-labelled nerve cells, where odour signals are combined with vision, where traces of the image finally disappear in decisions such as ‘avoid’ and ‘attract’, or where meaningful visual cues are stored in memory. We do not even know whether memory is located at every synapse where the signal passes, or in special localized centres, or in both. A similar state of ignorance applies to every other animal brain, but the bee is one animal where progress is possible, perhaps with the aid of large tropical species.”

Natural Nicotine Heals Honey Bees

NEONICOTINOID INSECTICIDES (e.g. thiamethoxam, imidacloprid, clothianidin) developed at Bayer Japan as safer alternatives (e.g. to human spray applicators) to the natural nicotine once widely used by farmers and gardeners, is now suspected of contributing to honey bee health problems like learning disorders and colony collapse. In contrast, natural nicotine, found in honey produced by bees working tobacco fields, as well as in pollen, nectar, leaves and other plant parts, is a nutrient and medicine helping to heal weak honey bee colonies, said Susan Nicolson of South Africa’s University of Pretoria at “Entomology Without Borders,” a joint meeting of the International Congress of Entomology (ICE) and the Entomological Society of America (ESA) in Orlando, FL.

Natural nicotine, even if produced organically in a sustainable recycling sort of way from tobacco waste products, is mostly shunned in organic farming and gardening. “Over 120 million sites will be returned on a web search on tobacco, but most will not be associated with plant science,” wrote USDA-ARS researcher T.C. Tso in Tobacco Research and Its Relevance to Science, Medicine and Industry. “Many plant scientists in academic institutions cannot obtain grant support for projects using tobacco as a research tool. Some even have to avoid tobacco because of the applying of ‘political correctness’ to academic research. The tobacco plant has served as a valuable tool since the dawn of plant and biological sciences, so it is indeed a great loss to scientific progress that a research tool already invested with so many resources and about which there is such abundant knowledge and such great potential for new advancement is now being wasted.”

Honey bees readily consume bitter alkaloids such as nicotine mixed in sugary plant nectars. Adult honey bees excel at detoxifying alkaloids such as nicotine, which should not be surprising, as survival depends on it. Younger, larval honey bees have fewer enzymes to detoxify nicotine, but also survive quite well even when their royal jelly contains high levels of nicotine. Honey bees and insects immune to nicotine, such as green peach (peach-potato) aphids, transform nicotine into less toxic butanoic acid. A knotty question naturally arises: If natural nicotine heals honey bees, why are synthetic neonicotinoids so terribly different? Are natural compounds like nicotine inherently more beneficial and their synthetic analogs (e.g. neonicotinoids) inherently bad, perhaps due to subtle differences in molecular structure? If bees and other pollinators are a major concern, perhaps natural product restrictions on nicotine need to be relaxed to provide competition to the synthetic neonicotinoids.

“Alkaloids, especially in the nicotine family, have been the main focus of tobacco research because alkaloids are the characteristic product of tobacco,” writes Tso. Dozens of other tobacco molecules are relatively overlooked, including sugar compounds providing least-toxic botanical insect and mite control. Anabasine (neonicotine), an alkaloid found in tobacco and other plants, has also been widely used as a natural insecticide. Strangely enough, anabasine is also an insect attractant and a poison gland product of Aphaenogaster ants. In a strange urban twist to the wild bird practice of lining nests with medicinal herbs emitting essential oils counteracting parasites: Researchers in Mexico discovered urban birds lining nests with cigarette butts to similar advantage. In times past, organic gardeners soaked cigarette butts in water to get a nicotine spray brew. Historically, most commercial nicotine insecticide used on farms and gardens was a sustainable tobacco waste extract.

There are 60-80 described tobacco or Nicotiana species, some available in seed catalogs and grown as ornamentals. Most Nicotiana species grow wild in the Americas, with some in Australia and Africa. “Tobacco plants are easy to grow and have a short growing period,” writes Tso. “Each tobacco plant may produce 14 g or about 150,000 seeds which may provide seedlings for 2 to 5 acres (1–3 ha) of field tobacco, depending on the type.” In Europe, oil extracted from tobacco seeds is being explored for an alternative bio-diesel fuel industry, with dry leftovers as animal feed.

Native American Nicotiana species are being integrated into China’s ancient agricultural interplanting tradition. When tobacco is interplanted in vineyard rows, tobacco roots and grape roots intermingle. Perhaps some sort of biological soil fumigation occurs. Whatever the mechanism, vineyards are cleansed of soil-dwelling phylloxera aphids, a pest that almost destroyed wine grape growing in France in the 1800s and is still a worldwide problem. According to the journal Chinese Tobacco Science, intercropping tobacco with sweet potato also alleviates soil and other pest problems, maximizing profits per unit area of land. Burley tobacco is intercropped with cabbage and other vegetable crops, according to the Journal of Yangtze University (Natural Science Edition).

Neonicotinoids are soluble in water and absorbed systemically by plants, and some are sprayed on urban lawns and landscapes. However, over 80% of synthetic neonicotinoids are applied to seeds prior to planting hundreds of millions of acres of corn, soybean, sunflowers and other crops. In Canada’s Ontario and Quebec provinces, 100% of corn seed is treated with neonicotinoids, said Nadejda Tsvetkov of Toronto’s York University at “Entomology Without Borders.” Though neonicotinoids were seldom found in corn pollen samples, somehow, perhaps by water transport, neonicotinoids are finding their way into clover and willow tree pollen far from corn fields.

“For a lot of farmers it is hard to get seeds untreated, especially corn,” as commercial seed is routinely treated with neonicotinoids regardless of need, said the University of Maryland’s Aditi Dubey at “Entomology Without Borders. In Maryland and other mid-Atlantic USA states where low pest pressures are the norm, neonicotinoid seed treatments are both unneeded and counterproductive. In 3-year Maryland rotations with double-cropped soybeans, winter wheat and corn, sowing seeds treated with thiamethoxam or imidacloprid reduced beneficial predatory ground beetles and increased slug damage to crops. Mid-Atlantic USA farmers typically apply 4 unnecessary prophylactic seed treatments every 3 years. Besides reduced biocontrol and more pest damage, soil accumulation over time is a disturbing agro-ecosystem possibility.

Alternative seed treatments include natural plant hormones such as salicylic acid and methyl jasmonate, which induce a natural immunity called induced systemic acquired resistance (SAR). Crops such as lettuce and argula (rocket) grown from seed treated with salicylic acid and methyl jasmonate also release volatile gases repelling pests such as sweet potato whitefly, a major worldwide pest, said Ben-Gurion University’s Mengqi Zhang at “Entomology Without Borders,” a gathering of 6,682 delegates from 102 countries. Numerous botanical materials and microbes have also been investigated around the world as alternative seed treatments.

A proactive approach to honey bee and bumble bee health includes a diversified landscape sown with herbs and medicinal botanicals for self-medication, not just natural nicotine from tobacco nectar or other sources. Thymol, an essential oil found in thyme and many other plants, is already sprayed in hives by beekeepers to combat Varroa mites. At “Entomology Without Borders,” North Carolina State University’s Rebecca Irwin reported laboratory choice tests where bumble bees rejected nicotine. In field tests, bumble bees were given a choice of different colored flowers each with a different botanical such as thymol, nicotine, anabasine and caffeine. Bumble bees only selected flowers with thymol to self-medicate. Interestingly, thymol and other herbal essential oils also synergize nicotine, boosting effectiveness against disease pathogens and perhaps also minimizing the likelihood of colony collapse.

Landscapes and hedgerows sown with medicinal plants such as thyme, sunflower and foxglove minimize bumble bee disease transmission, said Lynn Adler of the University of Massachusetts, Amherst. The current USA farm bill will actually pay farmers to plant bee-friendly sunflower edges or hedgerows around canola fields. Antimicrobial and medicinal honeys derived from sunflower, bay laurel (Laurus nobilis), black locust, etc., also effectively combat bee diseases like chalkbrood and foulbrood, said Silvio Erler of Martin-Luther-Universität in Halle, Germany at “Entomology Without Borders.”

Bee pharmacology is also useful in human medicine. In Oaxaca, Mexico gangrene is stopped and wounds are healed by combining maggot therapy and honey, reported Alicia Munoz. Maggot therapy uses sterilized (germ-free) green bottle fly maggots to disinfect and cleanse wounds by eating unhealthy tissues and secreting antibiotics, allowing healthy pink tissue to grow back under honey-soaked gauze. This cost-effective approach reduces hospital stays, lowers morbidity and can eliminate the need for surgery. It may sound yucky, but for diabetics and patients with bed sores or wounds where surgery is medically impossible, a few maggots and a little honey is preferable to amputating wounded or infected limbs.

Cancer-fighting bee propolis products were touched upon at “Entomology Without Borders” by Chanpen Chanchao of Chulalongkorn University in Bangkok, Thailand, where hives of stingless bees are reared like conventional honey bees. Cardol, a major component of propolis from the Indonesian stingless bee, Trigona incisa, causes early cancer cell death by disrupting mitochondrial membranes and “producing intracellular reactive oxygen species (ROS).” ROS are essential to energy, immunity, detoxification, chemical signaling, fighting chronic and degenerative diseases, etc. Cardol “had a strong antiproliferative activity against SW620 colorectal adenocarcinoma,” killing colon cancer cells within 2 hours, followed by complete cell necrosis within 24 hours. Thus, cardol is an “alternative antiproliferative agent against colon cancer.”

Earthworm Compost, Medicinal Honey & Fewer Hive Sprays Avert Bee Collapse

HONEY BEE COLONY COLLAPSE DISORDER and subtle learning and memory pesticide effects were among Biocontrol Beat topics detailed in Feb. 2011 (Honey Bees, 24-Hour Surveillance Cameras & Pesticides). For many attendees of Entomological Society of America (ESA) annual meetings, the two reports on pesticide effects on honey bees and bumble bees in the 30 March 2012 issue of Science magazine were just two more data bits, nothing particularly surprising; albeit good headline news fodder and a bit troubling. Perhaps a slight feeling of déjà vu for those familiar with Rachel Carson and her book of more than half a century ago, Silent Spring.

To imbibers of energy-boosting, nervous system stimulants like coffee, tea, and the many other caffeinated beverages flooding the marketplace, the idea that a common natural (e.g. botanical) or synthetic chemical might affect behavior is almost a no-brainer, though not necessarily self-evident. Caffeine has gone from fruit fly studies to mosquito control remedy recently. Natural nicotine from tobacco family plants has had almost an opposite trajectory, having once been widely used (e.g. burned as a fumigant) and recommended (e.g. soaking cigarette butts in water) for pest control in agriculture, greenhouses, and organic gardens; and now shunned because of its toxicity to humans and beneficial insects.

Neonicotinoid pesticides, like the widely used imidacloprid, had their design inspiration in natural nicotine molecules; but are safer to humans and other animals. But perhaps not totally without adverse effects, if indeed it is possible to have a substance that is toxic and yet totally safe. The Science reports associate neonicotinoid chemicals like imidacloprid with reduced bumble bee colony size and queen production, as well as lower honey bee survival and foraging success.

Though the scientific data will be subjected to further debate and future studies may confirm or refute the results, Science magazine writer Erik Stokstad, in an accompanying news and analysis, marshaled a stunning statistic to go with the reports: “In the United States alone, 59 million hectares of crops are protected by systemic pesticides. Seeds are treated with these neurotoxins before planting, and the poison suffuses the tissues, pollen, and nectar…”

Nonetheless, as ESA annual meeting habitués may know: genetics, pathogens, parasites, and beekeeper practices apparently also figure into the still mysterious honey bee Colony Collapse Disorder (CCD). Perhaps aptly for a confusingly mysterious disorder, CCD, the acronym for Colony Collapse Disorder, is confusingly the same as the Community College of Denver, charged-coupled devices (like those capturing images in digital cameras), Confraternity of Christian Doctrine, and The Convention Centre Dublin, to mention but a few highly-ranked “CCD” terms in Google.

Those who put their faith in scientific panels, better testing, and more government regulation will be heartened to know that Stokstad says more is on the way in Europe and the USA. Those wanting to do something practical right now to help the honey bees and native bumble bees pollinating their backyards and fields might find more encouragement in some of the presentations coming out of the Entomological Society of America (ESA) annual meetings.

For example, North Carolina State University soil ecologist Yasmin Cardoza, who has shown that earthworm compost produces plants more resistant to caterpillar pests and aphids, more recently told the ESA that amending a cucumber soil (model system) with earthworm compost (vermicompost) helped bumble bees and other native pollinators become heavier, healthier, and more fecund.

Cucumber plants grown in soils amended with earthworm compost had flowers (pollen, nectar) with significantly more protein and a bit more sugar. These more nutritious flowers grown with earthworm compost attracted more bumble bees and native pollinators. Plus the bumble bees had more and larger ovary cells and egg tubes (i.e. an indication of enhanced reproduction), weighed more, and had fewer disease pathogens. Whether earthworm compost can reverse or prevent Colony Collapse or create Colony Expansion would make for an interesting study.

Beekeeping methods also take a hit for exacerbating honey bee problems; and are illustrative of how mites, insect pests and pesticides make for the type of challenging problem that in previous centuries were solved by privately-funded freelance scientists like Louis Pasteur. Pasteur’s freelance entomological endeavors included almost single-handedly rescuing the nineteenth-century silk industry from a similar mysterious collapse of silkworm colonies (insect colonies seem particularly prone to epidemic collapse when you want them; but resistant to collapse when you would rather be rid of them, like termite and fire ant pests). Rene Dubos’ account in his 1950 book, Louis Pasteur Free Lance Of Science, is well worth reading for free on the Internet (pdf, Kindle versions). By early twenty-first century standards, Pasteur seems almost like a Rambo of science, accomplishing with a few assistants what would seem impossible today.

Even if the cause of honey bee colony collapse is still mysterious, like silkworm colony collapse was prior to Pasteur, there is no doubting the reality of the problem.

“In Virginia, the number of managed honey bee colonies have declined by about 50% since the late 1980s due to the introduction of parasitic mites,” Virginia Techie (Blacksburg, VA) Jennifer Williams told the ESA. “Excessive reliance” on fluvalinate (a pyrethroid miticide) and coumaphos (an organophosphate miticide) have “been implicated in numerous problems to honey bees, including impaired reproductive physiology, reduced ability of colonies to raise queens, reduced sperm viability in drones (males), and increased queen failure and loss.” Often these miticides are found in combination with imidacloprid (systemic insecticide), chlorothalonil (broad-spectrum fungicide), and the broad-spectrum antibiotics oxytetracyline and streptomycin used by beekeepers to combat American foulbrood disease in honey bee hives.

Fluvalinate, coumaphos, coumaphos-oxon, and chlorothalonil are found in almost half of North American honey bee colonies at ppb (parts per billion) levels that can be acutely toxic. Combining miticides, pesticides, and antibiotics is a toxic cocktail recipe boosting honey bee mortality 27-50%, according to Williams. In other words, it is a vicious circle in which beekeeping practices (e.g. miticides, antibiotics, substituting sugar water for honey) may have deleterious effects offsetting curative effects on already weakened and mentally confused bees feeding on plants treated with pesticides rather than healthy composts like those being studied by Cardoza.

As if honey bees did not have enough health problems, the small hive beetle (Aethina tumida) is now part of the mix. “In their native range in South Africa, these beetles cause relatively little damage,” Natasha Wright of the University of Arkansas told the ESA. “However, they can be destructive to honey bee colonies in the United States and Australia. The adults and larvae feed on bee brood and bee products. They also cause honey to ferment, which results in unsellable honey. Little is known about the biological control agents.”

“Identifying new mechanisms that support honey bee health will be pivotal to the long-term security and productivity of American agriculture,” Emory University’s Lydia McCormick told the ESA. “Hydrogen peroxide is a potential natural defense/stress response to small hive beetle,” a pest which can devastate a honey bee colony in weeks or months. Not to knock beekeepers, who have enough problems already, but their practice of feeding bees sugar water rather than honey laced with hydrogen peroxide may be part of the problem. Honey bees produce more hydrogen peroxide in their honey to combat stressors like the hive beetle.

“Extremely low concentrations of hydrogen peroxide in sugar-water fed samples may represent a problem in this common method of hive management,” said McCormick. “Honey bees may selectively regulate higher brood honey hydrogen peroxide as a strategic oxidant defense. Given that brood cells contain honey bee larvae, high honey hydrogen peroxide may help protect against pests.” Indeed, small hive beetle survival is lower with hydrogen peroxide in the honey.

Honey containing hydrogen peroxide has been marketed for its antibacterial, wound healing, and skin care potential; and prescriptions for medical-grade honey are a possibility. New Zealand professor Peter Charles Molan published an interesting historical review on honey for wound healing in 2001. Besides hydrogen peroxide, honey may have healing botanical compounds (phytochemicals). Perhaps the bee’s loss is humankind’s medical gain. Though if the bees are lost as pollinators in the process, it is not a sustainable practice in the longer-term.

Honey Bees, 24-Hour Surveillance Cameras & Pesticides

HONEY BEE HEALTH had the entomologists buzzing and the grad students searching for answers at the Entomological Society of America (ESA) annual meeting in San Diego. For several years now specialists have been spinning speculative theories as to why the pollinating honey bees of commerce, mostly the species known as Apis mellifera, have been in such sad shape. Isaac Newton had the proverbial apple bonk him awake to gravity. Bee entomologists have not yet had that magical bee sting in the butt “Aha” moment.

But there seems no getting away from the problem, as keepers of bee hives an ocean away from the USA are also getting stung with big losses, from what is dubbed colony collapse disorder (CCD). What has entomologists scurrying to their Petri dishes and bee hives and firing up surveillance cameras, chromatographs and mass spectrometers is a study titled “High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health.” Christopher Mullin of The Pennsylvania State University, a self-described connoisseur of how poisons work, and several colleagues “found 121 different pesticides and metabolites within 887 wax, pollen, bee and associated hive samples” from 23 states and one Canadian province. Enough to induce sleep-loss and second thoughts about the health and sleep-inducing effects of commercial honey products.

Surveillance cameras, 24-hours a day, are the best way to monitor and gather numerical data on how pesticides affect honeybees, Cornhusker grad student Bethany Teeters told the ESA in her prize-winning poster, “Bees under surveillance.” Being more video than even an insomniac can sanely watch, the University of Nebraska-Lincoln entomology lab delegates the task to “state-of-the-art detection” software: namely EthoVision XT, which Noldus Information Technology calls “the most widely applied video tracking software that tracks and analyses the behavior, movement, and activity of any animal” from “lab animals in mazes to farm animals in stables.” No doubt what Geoge Orwell would have used in his Animal Farm novel, had he written it in 2011 rarther than 1946.

“Honey bees are exposed to sublethal doses of pesticides on a regular, often chronic, basis,” Teeters told the ESA. “For instance, the pyrethroid tau-fluvalinate (Apistan(R)) is one of many pesticides applied directly into the hive to control the parasitic mite Varroa destructor. Although tau-fluvalinate is considered safe for honey bees, potential effects of sublethal intoxication remain unexplored.” Same goes for coumaphos, also used to treat for Varroa mites.

“Honey bees may also encounter sublethal doses of pesticides while foraging,” said Teeters. “Systemic pesticides, including the neonicotinoid imidacloprid, have become prominent in U.S. crop pest management. This raises concerns about the consequences of sublethal exposure to systemic pesticides in nectar and pollen that honey bees visit in addition to chronic exposure to residues in the hive. Decline in colony health has been associated with ppm (parts per million) pesticide residues in hive products, and the neonicotinoid can impair honey bee health at ppb (parts per billion) levels.”

Teeters surveillance videos of bees exposed to sublethal pesticide doses in Petri dishes revealed that bees exposed to tiny traces of tau-fluvalinate spend more time socially interacting. Bees exposed to imidacloprid spend less time socially interacting and more time eating. Next step is studies to see if this is true in actual honey bee hives, and whether colony health is impacted.

Natalie Boyle, a graduate student at Washington State University in Pullman, studied the effects of Varroa mite pesticides on honey bee hives in Moscow, Idaho. Honey bee adults stressed by miticide residues died sooner and did less reproductive swarming. But they compensated with increased brood production. “While our results are preliminary, if we find that pesticide residues in brood comb adversely affect colony health, it would suggest that regular brood comb replacement in beekeeping operations might be a suitable management strategy,” said Boyle. “Similarly, approaches to reduce miticide applications in beehives and pesticide exposure in agricultural field settings would be highly beneficial.”

Back at The Pennsylvania State University, graduate student Daniel Schmehl noted that the Varroa mite-killing chemicals coumaphos and tau-fluvalinate were found in almost every honey bee hive sampled in North America. Furthermore, these two chemicals were “associated with reduced queen weight and reduced ovary development.” After six days chronic exposure to tau-fluvalinate in cage studies, worker bees were less attracted to queen bees. This was possibly “due to changes in pheromone production from the queen or pheromone recognition by the workers.”

On the West Coast, at the University of California, San Diego, graduate student Daren Eiri explored how sublethal doses of the pesticide imidacloprid can subtly alter foraging habits in ways that weaken honey bee colonies. A common lab assay used to assess foraging is stimulating the honey bee antenna with sucrose, which elicits the proboscis (tongue) extension reflex (PER). PER is the lab equivalent of natural honey bee behavior in the field when foragers are stimulated by nectar. The pesticide seemed to make the bees “become pickier when foraging for nectar sources, possibly limiting the colony intake and storage of their only carbohydrate.” Pollen foraging may also be reduced, and “the colony would therefore suffer a protein deficit, resulting in lessened brood production and a dwindling population.”

Though the mystery of colony collapse disorder (CCD) is far from solved, current agriculture practices do not seem to be making honey bee colonies healthier, to say the least. But the collapse of the imported honey bee may have a silver lining: It is spurring agriculture to turn to previously neglected native pollinators. But the rise of the native pollinators is another story, for another time.