Oh, had we but seen this video a few days earlier, in time for Halloween!

A three-minute thesis competition is a contest for PhD students in which they condense their thesis into a three minute presentation comprehensible to an intelligent audience lacking any background in the research area. Doctoral candidate Samuel Ramsey was the winner in such a competition at the University of Maryland and will go on to the worldwide competition. Congratulations, soon-to-be-Doctor Ramsey!

To present his findings even more briefly than the video, we have been assuming that varroa mites chiefly live on bee hemolyph but actually feed mainly upon the tissues in the bee’s abdomen known as fat body, a name that does not do justice to its nine important functions. Denied this food source and fed on only hemolyph the varroa do not live as long nor reproduce as well. So with a slightly strained metaphor we have been trying to stake vampires when we need a silver bullet for werewolves.

So it’s werewolves not vampires. And it’s Istanbul not Constantinople.

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Seeming queenless is her one weakness.

Dorcas has been confusing us since June when we posted about finding her apparently queenless and broodless but calmly carrying on. Since then we have been able to check on her only infrequently either because we were giving a potential queen time to develop and start laying or because we simply lacked time during spells of suitable weather. When we did check we ever saw neither hoped-for sign of a laying queen nor dreaded evidence of laying worker.

We were able to more frequently observe her entrances and never saw anything amiss there. Traffic was lighter than at Clarissa or booming Beatrix but regular. No robbers. Just foragers going forth and returning, even some optimists heavily laden with pollen. And their numbers did not seem to increase but neither did they diminish. We did once see orientation flights but the timing was such that it could have been from the transplanted comb.

This last Sunday we finally had time and weather to inspect all three hives, beginning with devious Dorcas, the conundrum of the season, to find that she had a queen-in-hiding laying for all she was worth when we were no longer looking. Brood! Capped worker brood! Larvae! Dripping with nurse bees! And that is quite enough use of the exclamation point but we were inexpressibly relieved and elated. At least until we performed a sugar roll and measured thirty-four(34) mites in the sample! Oh, blast. Another exclamation point. You will forgive us when we point out that this measurement means over eleven(11) mites per hundred bees, which Bee Informed Partnership says is a level indicating “Loss of colony likely. Intervention is essential to decrease the threat of horizontal transmission (spread) of mites to neighboring colonies.” We immediately applied Mite Away Quick Strips(formic acid). She will surely need a second dose in a week and we must not be tardy. If weather will not permit time for another sugar roll then we shall simply raise the roof long enough to apply a second treatment and check mite levels again at a later date.

With such a high mite count in Dorcas we expected the worst for Clarissa and Beatrix but counted only a single mite in the former’s sample and none at all in the latter. Almost unbelievable good news. But bees may yet drift between hives so we shall have to remain vigilant against hitchhikers from Dorcas.

Where did the last two weeks go? On the eighth we visited the hives again to follow up on our first mite treatment.

Clarissa – We removed the old MiteAway Quick Strips and performed another sugar roll. The mite count was 7 (down from 16) for 21/3 mites per hundred bees. Not strictly high enough to treat but as we started with such a high count and are going into autumn we applied a second dose of strips.

Unrelated to mites, we spied a pair of bees energetically attacking a wax moth larva on the floor. We assisted by chopping it in twain with a hive tool after which the attackers lost interest. Apparently bees are sticklers for respecting job descriptions and killing intruders is very different from hauling out rubbish even when that includes dead intruders.

Dorcas – She continues to confuse us. No eggs or larvae. No queen spotted but no laying workers either. The brood frames we had transferred showed capped cells and we noticed a queen cell torn open at the side.

Beatrix – We left this hive alone.

Annabelle – Still sitting in the woodshop with only minimal progress towards redeploying her.

And that is the late report. We should have visited them again a week after that but life, weather, the usual. The same things that will probably keep us from inspecting them again as soon as we should.

While we have not made any serious effort at preserving our anonymity we have been coy about mentioning our names on the blog and shall likely continue that habit in future posts. But for this post the curious reader can find us out as the authors of “Honey and Preserves” in the 2017 Summer newsletter of the Southeast Michigan Land Conservancy.

We regularly join fellow SMLC members with our saws and shovels at the nearby preserves to work on projects like planting pollinator meadows, keeping trails clear, and the like. During those sessions it is entirely possible that we may have held forth on honeybees once or twice. Or thrice. Okay, nearly every time but they ask us questions. It is not our fault. Ahem. So when it was decided that the summer issue of the newsletter would focus on the importance of preserved land and its connection with area residents we were asked to write a short article making that connection to beekeeping. We are too pleased with ourselves not to briefly break cover and share the news here.

When we first mentioned that we would be posting detailed follow-ups of the talks we attended at the Michigan Beekeepers Association Spring 2017 Conference, there was a particular request from a reader for a report on Dr. Seeley’s presentation on plastic foundation, Plastic Foundation: Good for Beekeepers? Good for Bees?, and the interesting thing we non-users learned. Months later we finally present that report.

Plastic foundation is food grade plastic covered in a very thin layer of beeswax1. It is available in two forms, as sheets to be inserted into wooden frames just as wax foundation is and as complete one-piece plastic frame including foundation. The general conclusion is that it has advantages for the beekeeper.

  • Frame assembly is made simpler, especially if already part of a one-piece frame.
  • The plastic back makes strong combs that do not blow out in a centrifugal extractor.
  • It is better for pre-supering.2 Practiced in apiaries that are hard to visit frequently, this is the procedure of adding supers of undrawn comb far in advance of a nectar flow. Wax foundation thus used gets dry and nibbled.

But Dr. Seeley had questions about disadvantages for the bees.

  • Does it hinder comb building?
  • Does it reduce honey production?
  • Does it interfere with waggle dancing?

The answer to the first two is ‘yes, but there is a fix’, the first part of which is to paint a thicker layer of beeswax on the plastic sheet3. Dr. Seeley suggests using disposable foam brushes. That may suffice but one can also try to establish ideal conditions for comb building: a heavy nectar flow and hive full of brood and nectar. The middle-aged bees, which are the nectar-receivers and wax-producers, will be strongly motivated to draw out comb to make room for the incoming flood.

That leaves the question of whether or not it is a fully suitable substrate for waggling. And here comes the information we found so interesting, if only because of the many hours spent so long ago surrounded by electronics equipment in physics labs . The comb consists of relatively thin cell walls rising from the foundation and having a thicker rim at the top. A waggle-dancing bee shakes this rim to attract followers, producing vibrations centering around two frequencies, 15 Hz with its body and 250 Hz with its wings. Followers of the dance detect vibrations in air and through the comb with the subgenual organ in each leg, seemingly over a greater distance on open comb than on closed comb.

In one of his few experiments not involving watching individually marked bees in an observation hive placed in a contrived environment, Dr. Seeley used an oscillator in a lab to find that comb on plastic foundation dampens the 250 Hz signal but not the 15 Hz component.4 But then he returned to his habitual tricks to observe in the field that there was no difference in recruiting effectiveness for any of wax foundation, plastic foundation in wooden frame, and one-piece plastic frame with foundation.

One question raised by the audience that was not investigated was whether the plastic outgassed significantly to harm the bees or build up in the wax. But then Dr. Seeley’s focus is honeybee communication rather than general health and that investigation would have required an entirely different array of laboratory equipment.

In conclusion plastic foundation has advantages for the beekeeper and, even with different acoustic properties than wax, no disadvantages for the bees if the beekeeper makes an effort to get them to draw comb upon it.


1Very, very thin. Jokes were made about the nearly monomolecular, almost homeopathic thinness of the wax coating.
2An audience member pointed this out.
3The same audience member pointed out that a version with thicker wax coating is available.
4It is common for higher frequencies to be more attenuated than lower due to acoustic heating of the medium.