[Bonus] Short: Dr. Dewey Caron - Mite Management and Bee Learning Breakthroughs

[Bonus] Short - Dr. Dewey Caron - Mite Management and Bee Learning Breakthroughs

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Jeff: Welcome to Beekeeping Today Podcast Shorts, your quick dive into the latest buzz in beekeeping.

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Dr. Dewey Caron: Hi, I'm Dr. Dewey Caron. I come to you from Portland, Oregon. I present another audio postcard on communication in my continuing series of once monthly Beekeeping Today Shorts. This month is August. The topic is, mites. For these audio postcards, I have been discussing communication on three levels: bee scientist to beekeeper, beekeeper to bee, and bee-to-bee. My last beekeeping today postcard, I discussed summer and whether you had communicated to your bees to fill it up. Management of surplus. I sure hope your bees were listening, and by now you have removed and extracted surplus honey and the heavy lifting hot sticky work of extracting will soon be, but distant memory.

August is a critical month for mite control before their numbers explode and get too high. This is the time to assist our bees. We want to communicate, keep mite numbers low. By August, you hopefully have completed a couple of instances of mite monitoring. Maybe you decided you need to do some control this month already if your mite numbers exceeded what are recommended 2% level. If you have not monitored, it is overdue; don't put it off. The bee scientist, the beekeeper communication is the Honeybee Health Coalition tools for overall management.

A committee is currently revising this current edition. This revision is necessary as we need include several new products. In this Beekeeping Today Short, I'll discuss what's new,as our newest edition will not be finished until later this season. Our tools revision, like previous versions, emphasizes the value of having a plan. There's no one silver chemical or management bullet that works; thus rotation of chemicals and management is needed. Your plan needs to be flexible to accommodate seasonal, environmental, and mite differences.

Don't hesitate to develop a new plan, especially if the communication from your bees in the form of dead colonies in the spring says your plan didn't yield hope for success. A good plan is one that can be adjusted. First up is brand new approach. The US Environmental Protection Agency, we call it EPA, will register data scanner. This is a double-stranded RNA, and we use the designation dsRNAi, going to register that for control against varroa mites. The product that is closest to market is Norroa, developed by GreenLight Biosciences. It's been tested for over 10 years and deemed safe. Tests indicate it will be highly effective.

Much of our past efforts is to control mites on adult bees late in the year. We make our bees stronger to rear sufficiently large populations of fat fall bees. This product is designed to make the mites weaker. How does it work? RNA is the messenger from the DNA of a cell nucleus that carries the genetic code to cellular process that tells cell components how to make something. Something like hormones, pheromones, cell walls, mitochondria, more cells, et cetera.

While the scanner, the dsRNAi, targets a specific mite protein that interferes, that's that "i" of RNAi that interferes with cellular protein building in the developing mite. Because the message is wrong, mite reproduction is halted. Reproduction of mite babies fails. While the scanner is a cellular message specific to mites, it has no effect on host bees or humans. The material is administered in pouches placed on top of frames or on the bottom board. One application lasts up to 18 weeks. There are no temperature restrictions.

With trophylaxis, high bees distribute to nurse bees who in turn, feed it to the developing bee larvae in the brood food. After the cell is capped, pupae have enough in their body, so the message to build protein in the baby mites is disrupted. Founders female mite reproduction inside the capped pupa cell fails. It only targets mites, not the bee pupae, weaker mites. As an all-new technology, it would be more expensive compared to the present controls. Eric Walgren, a marketing lead, and Adam Pachel, a six-year veteran in the North Dakota EPA Inspection and technical manager, enthusiastically indicate the results will justify the added expense.

EPA has gone slow on licensing. They had to be sure that licensing this new tool would not affect bees or humans. For this reason, because normal functioning of government agency in Washington has been disrupted for the past six months, the product will not likely get its final okay until late this year. A second novel mite control registered by EPA is Mite Bee Gone, a new varroacide product containing L-glutamic acid, an active ingredient that has not previously been included in registered products for use in beehives. The developers is Paul Niemczura of Pennsylvania.

It is incorporated into the strips to be hung in the brood area. As a contact, it must be walked on by the bees. L-glutamic acid targets mites where they reproduce inside the brood cells. The treatment not only kills adult mites but also interrupts their reproduction. Unfortunately, developer Paul, chemist and industrial chemical product developer, and a 25-year beekeeper, while he has conquered the R of R&D, has his issues with the development phase of a marketable product, the D part of R&D. He is struggling with producing a product ready for market.

He has sold some strips to Pennsylvania beekeepers, and now he has teamed with CH Biotech, an ag chemical development company in Taiwan that markets L-glutamic acid as a plant growth stimulant. Paul is hopeful to have more product on the market later this year. You can read his story in endnotes that I have, references under his Mite Bee Gone website. It's a story that's worth listening to.

The tools revision will include changes in established chemical treatments as well. The chemical treatment that has become most popular of the several organic alternatives is oxalic acid, oxalic acid dribble, or vaporization that apply during the overwintering period when colonies have no or very little brood is commonplace. It helps surviving colonies from winter have few female varroa mites as spring buildup starts, but we have known it is less effective tool when bees are rearing brood. Now, during the active brood session, oxalic acid extended in what we call OAE, oxalic acid extended, has an approved product, VarroxSan. It consists of impregnated frame draping strips. It's contact that the bees must walk on to be effective.

VarroxSan is licensed legal, OAE. OAE has been readily adopted by beekeepers, both this compound and the way to do it for a homemade OAE product. What I need to convey is the importance of following labeled directions for use of VarroxSan. Beekeepers have been laying the strips on top bars or moving the strips to frames that edges the brood box, very edges, or putting the strips at the ends of the frames to try to reduce the negative of strips interrupting brood rearing. Queens do not care for the chemicals, so they will not go beneath these strips to lay eggs. Where it drapes, then there's a strip that is not without brood.

B2Bee Health North American Tech represented Dave Westervelt, retired Florida Apiary Inspector, says the directions must be followed to expect reasonable mite control. You need to put the strips where the bees will walk on them. Hanging between frames in the brood area is necessary. Do not lay the strips on top bars or move them away from where the nurse bees will have maximum exposure to the oxalic acid-containing strips.

Finally, in the tools revision, we cover the new formulation of Apivar. The pesticide chemical, amitraz, is still largely effective in varroa mite control for backyard beekeepers, but apparently less so for commercial beekeepers due to developing mite resistance to that chemical amitraz. Commercial beekeepers have been using off-label treatments, a practice known to hasten target resistance for ag chemicals. In other words, the mites themselves are becoming resistant. The standard Apivar has been reformulated as Apivar 2.0. The new formulation has a reduced pesticide amount. That's right, reduced, but it delivers a quicker and longer knock down due to the addition of an adjuvant chemical.

The treatment period can be extended up to 10 weeks, but there's no two-week withholding period before you can add supers. That's a big improvement. Tabs have been redesigned, so it's now easier to hang them between the frames. It is a contact, so bees have to walk on it. Sometimes bees move away, and you should still check after the first week after application to see that the strips are where the bees are. Apivar can still be used, but the company will gradually stop distribution and only sell Apivar 2.0.

To help revise or further develop your plan, I have listed booklets from the two major companies, Véto-Pharma and Vita Beehealth, at the end of this show, and two new studies of oxalic usefulness in season-long mite control used oxalic acid in combination with Apivar from Ontario and Quebec provinces in Canada. Let's go on to beekeeper to bee communication. What do we wish to communicate to our bees about mite control in August? Earlier, I talked about having a plan. In August, the beginning of the beekeeper's new year, is when we should be thinking about our plan for the new year.

I call your attention to a publication of seven UK authors on varroa control adherence published online in Entomologia Generalis, and its open access so you can look at it. Is widely understood that failure of beekeepers to adhere to proper and accepted treatment guidelines can adversely influence treatment efficacy. The authors use national annual survey data of 4,339 beekeepers in England and Wales between the years 2016 and 2020. Total sample of almost 19,000 counties. This included 11 different approved chemicals and 6 non-chemical treatment options, as they indicated what they were using.

They found over one-third of beekeepers engaged in at least some level of non-adherence. Keying this to overwintering success or failure, they could demonstrate that lower overwinter colony losses, that is, better colony survival, correlate to correct treatment timing. Beekeepers using either one or two correctly timed treatment products reported significantly better winter survival compared to those that had mistimed those applications. Timing was critical, but the product or the treatment that used itself had only limited influence on overwinter colony losses.

Not surprisingly, they concluded these findings suggest that varroa treatment non-adherence is a substantial driver of large-scale colony mortality. Their study illustrates the value of having a plan. Check that timing. It is critical.

Finally, now to bee-to-bee communication. I've been talking about those nasty mites, so I want to change this last segment and talk about something more appealing. Honeybee learning as illustrated by their dance language. I had a chance to listen to Dr. James Nieh of UC San Diego. He was our James Hamilton Research Excellence Award winner at the Eastern Apicultural Society meeting in the last week of July in New Jersey. One of his three presentations was about the discovery that the waggle dance of honeybees is improved by learning.

Discovery, honored by being featured on the cover of the prestigious Journal Science, through some novel experiments developed by Dr. Nieh and his collaborators, showed the importance of early social signal learning. He labels it one of the most complex known examples of non-human spatial referential communication, and this is the first time they are able to show that it occurs in insects. We know that honeybees help ensure the survival of their colonies by communicating the location of food sources to one another through a waggle dance, in which bees circle round in figure-eight patterns while waggling their bodies during the central part of the dance.

Performed at breakneck speed, each bee moves a body length in less than one second. The motions within the dance translate visual information from the environment around the hive and the location of the sun into the distance, direction, and even the quality resource to nest mates inside. Inside their hives, the direction a recruit bee is told to fly is changed from a sun position orientation used outside when they fly, to a gravity orientation of the waggling segments. Dancers can't just point to where the food is. How far to fly is encoded in a waggling segment. The longer the waggling, the greater the distance.

Bees begin to dance when they reach foraging age and always follow experienced dancers before they first attempt to dance. Then, through a series of very inventive series of experiments, it was shown that honeybees, like humans and songbirds, appear to have a critical period for language acquisition. The study was made possible by creating an observation hive of entirely newly emerged bees. Bees not exposed to the dances of their older counterparts, and then analyzing their first instances of dancing when they actually start to dance.

In this hive of same-age bees, the first bees, and they begin this at about 10 days of age to leave the hive as foragers were captured on their very first venture outside the hive. Some reward? Then they were immediately trained to a sugar-rich artificial feeding station. When they were released to fly back to the hive, their dancing was then captured on video, and then hours and hours of analysis of the video. These bees, without the opportunity to follow any dancers before their initial dance, performed significantly more disoriented dances with larger waggle angle divergent errors and the less typical pattern dancing. They moved all over that place. It wasn't in a nice, even pattern.

They also encoded distance incorrectly, waggling longer to give a distance beyond the actual distance to the feeder. They were misinforming sisters on what direction to fly and how far. Experience increased angle, direction accuracy, but untutored bees were never able to recover accurate distant courting. They always gave information too far. Thus, as with birds, humans, and other social learning species, for example, elephants and whales, and many others, honeybees benefit from observing others of their kind that have experience. Amazing learning ability for a creature with such a small brain.

In the end notes, I provide reference to the article, and there's also a nice YouTube reference that explains this discovery and its significance.

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Mites and bees learning, the bee postcard for this month. Mite control in August is critical to ensure colonies survive the coming winter season. The bee hive stock we have is not yet sufficiently developed to fight the mites alone. It's helpful to have mite reproduction under control by August. They are a formidable fall. I trust you are able to successfully communicate to your bees and to keep mite numbers low. Be proactive in your management. Be well.

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