Eating my words

I periodically look at the access statistics of this site. It gives me an idea of what’s popular, which subjects might be worth revisiting and which posts have sunk without trace into bottomless void of the internet.

Daily page views are only 50% what they were in June. Maybe it’s the chaos/excitement/disappointment (delete as appropriate) of the US election or the deja vu and crushing inevitably of Lockdown 2.0, but beekeeping appears to be getting less popular.

Or perhaps it just reflects the fact that it’s the end of the season and everyone is frantically catching up on all the tasks they postponed from earlier in the year when they were in the apiary 1.

That’s not to say that there is no beekeeping to do at this time of the year.

Mite corpses

I usually use Apivar for Varroa control. The active ingredient, amitraz, remains effective. I like Apivar as it works even at the lower temperatures we have in Scotland. In addition, the queen continues laying – in contrast to Apiguard for example – at precisely the time the colony needs to be rearing lots of long lived winter bees.

Double brood colony the day before Apivar treatment added

I insert the Apivar strips as soon as the summer honey supers are removed and at the same time as the autumn fondant blocks are added. This year the strips went in on the 28th of August. The mite drop is then monitored over subsequent weeks.

Or should be.

My continued absence on the remote west coast meant that the counts of mite corpses were a bit hit and miss this year 2.

Mite drops – colonies in the bee shed, autumn 2020

The counts were sufficient to determine the relative mite infestation levels and observe how they dropped over time. Unfortunately, they weren’t detailed or frequent enough to see real differences on a day-by-day basis.

I’d hoped to get this to discuss the influence of the reducing laying rate of the queen on apparent mite infestation levels, but that will have to wait until another year.

Mite drop data

The four colonies plotted on the graph above are in our bee shed. They are all within 4 metres of each other, and have been for at least a year. None have had any Varroa management this season 3 other than the Apivar added in late August.

Hives in the bee shed

One of the colonies (#1) has had sealed brood periodically removed for experiments. Hive #2 and #4 are on a double brood box, the other two are on singles. All the hives are Swienty or Abelo (poly) Nationals.

The first thing to notice is that there are very significant differences in cumulative mite drop over the first 40 days after starting treatment. Rather than graph these numbers, here’s a simple list by hive number:

  1. 73
  2. 697
  3. 597
  4. 120

Infestation levels can differ significantly, even in colonies within the same apiary. Or on the same hive stand. Monitoring a single hive as a sentinel for a complete apiary could be very misleading.

Hive #1 counts are probably lower because the colony is a bit weaker than the others (though that’s relatively speaking – many beekeepers would consider it quite strong). However, the drop is not significantly different from #4 which is a very strong colony. 

Throughout the treatment period shown (we stopped counting in October) the average mite drop per day from #1 and #4 never exceeded 5 which is satisfying low. There’s little else to say about these two colonies 4.

The high mite drop from colonies #2 and #3 is about as high as I’ve ever seen in my own hives in Scotland. 

Mite reductions

When I lived in the Midlands I saw higher counts. There’s a much higher density of apiaries and beekeepers there than in Fife, and it was more difficult to manage colonies to routinely have low mite numbers. I’ve always assumed this was due to robbing and drifting – isolation definitely helps – but my Varroa management was also a bit different (in both method and timing).

Hive #3 trace shows a typical reduction week on week over the treatment period. High at the start and negligible after about 40 days.

Colony #2 has a strange increase in mite drop in the third week of treatment. I don’t really understand this. One possibility is that the colony was robbing a nearby heavily-infested colony 5 during this period, with the foragers bringing back phoretic mites as well as the stores they’d robbed out.

In both these “high mite” colonies the mite drop after ~40 days was averaging 5 per day or less, which should be OK. They will be monitored again in mid/late November and after treatment with Api-Bioxal during a broodless period

For reference, colony #1 was broodless when checked on the 13th of October, a few days after the last count on the graph above. 

Apivar strip removal

The approved duration of treatment with Apivar is 6-10 weeks. I usually remove strips after 6 weeks if the mite drop is low and steady. There’s nothing to be gained from overtreating.

However, since I was aware of the high mite drop from colonies #2 and #3 I left the strips in for a bit longer, removing them on the 30th of October (i.e. 9 weeks). 

Used and removed Apivar strips

If beekeepers are to avoid Varroa acquiring resistance to Apivar it is very important that the miticide is used properly. Removing the strips within 10 weeks very important. 

I attended an online Q&A session with Luis Molero (Scotland’s lead Bee Inspector) organised by the SBA. In this he described finding hives on heather moors which still contained Apivar strips. These had presumably been left in the hive after a mid-season treatment, though whether by accident or design is unclear. 

This is poor practice on two counts; continued presence of low levels of the miticide would contribute to selecting amitraz-resistant mites and there is the additional risk of tainting the honey with miticide. 

Reading and writing

I spend a lot of my week stuck in the office reading and writing. Grants, manuscripts, strategy documents, complaints, the BBKA Q&A page, menus (well, OK, not menus … and relatively few complaints) etc.

As a consequence I rarely spend much time reading for pleasure. Months go by without me opening The Scottish Beekeeper, the BBKA Newsletter or ABJ. However, as the beekeeping season draws to a close I have a bit more free time and so periodically binge-read some of these to catch up.

The view from the office … another reason I’m behind on my reading

Usually, by the time I read something, it’s out-of-sync with the season. I find myself reading about queen rearing strategies in late October, or overwintering queens in early February. Much of this is promptly forgotten … unless I make notes and write about it here.

You could consider The Apiarist as a sort of aide memoire for this forgetful beekeeper 😉

However, a few weeks ago I read a letter to the editor in The Scottish Beekeeper on the perils of feeding fondant. I’ll paraphrase here both to avoid copyright issues and because I’ve lost (!) the particular issue the letter appeared in.

The gist of the letter was that the correspondent had lost several colonies when fondant had gone sloppy and dripped down between the frames, killing the colony in the middle of the winter. 

I sent a letter to the editor saying that I’d only seen this when the colony had perished through disease. Healthy colonies, clustering under unfinished fondant blocks, tended to keep nibbling away and so were not swamped by a tsunami of cold, syrupy fondant.

Or words to that effect.

Don’t speak write too soon

I’ve got a couple of Varroa-free colonies on the west coast of Scotland. Both were started from nucs in mid/late summer, built up well and collected a reasonable amount of nectar from the heather. I left this for them, nadiring the partially-filled super and – as I usually do – adding a block of fondant on a queen excluder.

Both colonies are in Abelo poly hives with open mesh floors and a 5cm block of Kingspan insulation under the polystyrene roof. This is typically how my colonies would overwinter 6.

Green thoughts in a green shade

Neither colony used much more than 6 kg of fondant as both brood boxes had ample stores. I therefore intended to remove the unused fondant ‘at some point’. 

For a future post here I wanted a photograph of the typical ‘stripes’ of brood cappings visible on a Varroa tray. Since these west coast colonies brood later in the season than my Fife bees I inserted a tray below one colony a couple of weeks ago.

‘At some point’ turned out to be today (5th of November).

To my surprise. the underside of the fondant block in the hive with the Varroa tray was distinctly soft and sloppy.

Sloppy fondant stuck to the top bars – this hive had the Varroa tray inserted.

In contrast, the other colony was much as I’d expected. No sticky fondant.

No Varroa tray, no sloppy fondant stuck to the top bars.

Clearly, under certain conditions, a fondant block can soften sufficiently to start to dribble down between the frames. It’s worth emphasising the colonies are in the same type of hive (floor, boxes and roof), in the same apiary and are of equivalent strength. The only difference is the presence of a well-fitting Varroa tray in one of them.

Eat my words

I think the explanation for the difference from a) my previous experience, and b) between the two hives pictured above, is straightforward.

It rains a lot on the west coast. In the last fortnight we’ve had 280 mm of rain, with today being the first mainly dry day 7. This was why I’d chosen today to remove the fondant.

With that much rain the humidity levels are also quite high. With the Varroa tray in place I suspect that that humidity levels within the hive were higher still. Under these conditions I suggest that the fondant absorbs water faster than the bees can consume/store it.

These conditions are quite specific and are only likely to be an issue for beekeepers (or bees!) living in areas of high and regular rainfall. The original letter to The Scottish Beekeeper was from a beekeeper in Dumfries and Galloway.

Fife and the Midlands – the only areas I have many years experience of beekeeping in – both have less than 750 mm of rainfall per annum. I’ve had hives with both fondant and Varroa trays in place for weeks without any problems.

In my letter to The Scottish Beekeeper I described the hive insulation but failed to mention the open mesh floor. D’oh!

It’s now time to quickly write a follow up to explain these recent observations.

This example rather neatly demonstrates the influence of local conditions … and the importance of trying to interpret what you see when opening a hive. 

Since I’ve now written about it (my aide memoire for a forgetful beekeeper 😉 ) I’ll hopefully also remember this lesson next winter.

Speaking

It’s turning out to be a busy winter for talks to beekeeping associations.

These are increasingly popular as association members realise the benefits they offer.

You don’t have to negotiate icy roads in the dark to sit for an hour in a draughty church hall. 

No longer do you have to squint at an image projected onto a creamy-yellow wall with an irritating picture hook in the middle of every slide.

You can sit in the comfort of your own lounge (or bath), sipping shiraz and occasionally staring at a nice picture on a high resolution screen.

At least, that’s what I’m doing … as well as talking a bit 😉

I still lament the lack of homemade cakes. 

However, I have taught myself to make pizza during lockdown.

Pizza

If I’m mumbling a bit when I’m talking you’ll know why 😉


 

Footnotes

  1. I’ve spent half of the last week up ladders doing precisely that.
  2. And I’m grateful to Luke in my lab for collecting some of the numbers.
  3. Which includes no enforced brood breaks (other than swarm control), no drone brood uncapping/removal etc.
  4. We’ve also monitored the virus load (DWV) in these colonies and it is very low.
  5. There are other hives in the apiary and several nearby apiaries within range.
  6. Or, for that matter, spend the entire season.
  7. Have you noticed that weather forecasters use the phrase mainly dry to mean ‘rain’ without actually saying ‘rain’?

32 thoughts on “Eating my words

  1. Eric

    I have been very disappointed with the new Abelo hives, continually getting a lot of moisture in the rails between brood box and super. I have had to wrap the hives in polythene or similar, tucked under the roof in order to keep the moisture levels in the hive at acceptable levels

    Reply
    1. David Post author

      Hi Eric

      These are the earlier version of the Abelo hives. Nevertheless, water can still pool behind the framerunners. You can just see it in this picture:

      Water in frame rebate

      The way to avoid this is to cut a small notch at one end of the runner to allow the water to escape (at least it will if the hive slopes slightly). I don’t bother doing this but was told this solution by another reader of this site.

      Cheers
      David

      Reply
  2. Susan

    In the US the requirements for Apivar are 42 days and if the brood cluster has moved significantly, move the strips there for 2 additional weeks then remove. 70 days seems as though it could lead to resistance more rapidly than manufacturer advice.

    Reply
    1. David Post author

      Hello Susan

      Apivar instructions

      I think the instructions must be different this side of the Atlantic … the 6-10 weeks I quote is lifted directly from the instructions on each packet of Apivar. I wouldn’t use it for longer than recommended … and tried to make that point in the post.

      A week here or two is unlikely to make much difference in terms of selecting resistance … leaving the strips in overwinter, or when the hives are taken to the heather moors is a different matter altogether.

      Regards
      David

      Reply
  3. Roger Gill

    I had thought you were more of a sublimated oxalic acid man than an Apivar man. Any particular reason for the change, other than the hassle of getting a 240v supply in the right place?

    Reply
    1. David Post author

      Hi Roger

      I generally use OA in midwinter and Apivar in the autumn. Frankly, I don’t think it makes any difference which miticide is used if it’s used at an appropriate time and applied correctly.

      At this time of the season (autumn) colonies are still brooding. A single OA treatment will miss 80-90% of the mites. To use OA you need to do multiple treatments. That’s a lot more work than just dropping a couple of strips in and walking away for a few weeks. In addition, repeat OA (as Api-Bioxal) vaporisation is not a VMD approved treatment. These are research colonies and have to be maintained according to the rules. I don’t want to get into trouble 😉

      Cheers
      David

      Reply
      1. David

        According to my friendly Bee Inspector, repeat OA (as Api-Bioxal) vaporisation IS a VMD-approved treatment (possibly because you’re using Api-Bioxal and can quote the batch number). In contrast, repeat OA vaporisation using another form of oxalic acid (such as the crystals I buy) is not a VMD approved treatment.

        Reply
        1. David Post author

          Hello David

          My reading of the VMD paperwork associated with Api-Bioxal is for single use. The labelling and instructions documentation (MS Word document, dated 2016 – see note below) includes the text:

          B) Posology and method of administration by vaporization:
          Use an electric resistance device for vaporisation. Fill the pan of the vaporizer with 2.3 g of the product. Place the appliance through the entrance of the hive under the bees, avoiding contact with the honey combs. Seal the entrance of the hive to avoid escape of the bees and smoke. Turn on the vaporizer following the manufacturer’s instructions for about 3 minutes and keep the hive shut for another 15 minutes. Cool down and clean the vaporizer after use to remove possible residue (max 6%, around 0.140 g). Use drinkable water for cooling and/or cleaning. Maximal dose 2.3g per hive as a single administration. One treatment per year.
          It is recommended to follow manufacture’s instructions in order to achieve maximum sublimation.

          (I added the bold to emphasise the relevant bit).

          I note that there is a post authorisation assessment document containing two references to repeat applications dated 2017 and 2020, but these aren’t mentioned elsewhere in other paperwork, so I’m not sure what they refer to.

          Perhaps your bee inspector friend is correct (I’ll ask mine) but it would be good to see something in writing for confirmation.

          Cheers
          David

          Reply
  4. Steve Riley

    We see a huge difference in mite loads between varroa susceptible bees and those colonies where bees are manging their own varroa loads (uncapping seems the key behaviour). Your blue and yellow hives may have such bees. Have you seen any signs?

    We don’t treat and that level of mite drop in the yellow and blues colonies would be up with the best of most hygienic bees.

    Reply
    1. David Post author

      Hello Steve

      Covid and lockdown prevented me seeing very much at all this year … I’ve only done about four inspections all season. However, many of my colonies in previous seasons have similar low mite drops. I suspect this is more to do with timely application of miticides and a mid-season brood break caused by swarm control. I’d be pretty certain that mite levels would explode if I didn’t treat. These are research colonies and I cannot afford to risk that happening. The DWV levels are regularly monitored and are about 10^5-10^6 per bee less than in many typically managed colonies.

      I just think these are Varroa-sensitive bees managed properly 🙂

      Cheers
      David

      Reply
  5. Chris

    Sloppy fondant.
    At one time I had sloppy fondant quite often.I put the fondant onto an excluder under an eke which is a super half filled with insulation and thus leaving space for the fondant and bees It didn’t seem to cause problems to the bees underneath on the frames, but there were bees becoming stuck to it. This year I’ve put the fondant into the hive onto a thick plastic wrapping opened to allow bee entry placed on the excluder.I did try putting it into foodwrap, but it looked as if the bees ate it. The bees leave an empty ‘bag’ ready to remove and replace. It also means that the time with an open hive is minimal. . I wonder if the original article you mention might refer to the often recommended practice of putting unwrapped fondant directly onto the tops of frames?
    Today I replenished the fondant and found that the remaining fondant was dry and hard, despite it being very wet for the last month.

    Reply
    1. David Post author

      Hi Chris

      I describe in gruesome detail how I feed fondant in several posts on the site – for example here. All of the fondant is left inside its original blue wrapping … on top of the frames.

      Bees do eat clingfilm-type food wrap. They also drag it down into the hive and it gets embedded into brace comb. When I feed fondant midwinter I place it inside a plastic food container and invert it directly over the top bars of the frames.

      Midwinter topup of fondant in food tray

      Cheers
      David

      Reply
  6. Matt Harris

    Good article, thanks

    I have also noticed a distinct difference between two brands of fondant, which is explained, I think, by the water content.

    The BFP fondant I have used has been quite dry. I think it has a water content of around 11% (but can’t remember where I saw this).

    In contrast, I recently started using Chocolate Falls fondant, which is 17% water, and it is noticeably softer. It might well drip in certain circumstances, though I haven’t had an issue myself. So that might be why the correspondent to Scottish Beekeeper had an issue too. I like it because I suspect it is less likely to go hard in winter, but we’ll see.

    Reply
    1. David Post author

      Hello Matt

      Interesting. I’ve used BFP and whatever the stuff is this year which seemed very similar. I’m not too worried about the fondant going hard in the winter – most colonies finish it well before the cold weather starts and I think there’s usually enough moisture on the sidewalls to help them continue to use the fondant.

      90% of my colonies finished all their fondant within 6 weeks of it being added. These two colonies barely had space in the brood box for any more stores and it was only the never-ending rain that stopped me removing the remnants earlier.

      Cheers
      David

      Reply
  7. Mike

    Hi, liked your article as I have used apivar this year for the first time. You mentioned ‘ Both colonies are in Abelo poly hives with open mesh floors and a 5cm block of Kingspan insulation under the polystyrene roof. ’ presume 5cm thick so do you use an eke ( what thickness, or use a super) with insulation around the fondant?

    Reply
    1. David Post author

      Hello Mike

      My crownboards have inbuilt insulation. Alternatively I cut up blocks of salvaged Kingspan, seal the edges with gaffer tape and simply place them directly over the crownboard.

      Kingspan insulation

      In the bee shed, most hives don’t have roofs and are just topped with a block of Kingspan.

      Cheers
      David

      Reply
  8. Jonathan Court

    Hi David,
    I haven’t visited your site as often over the last month or so because I remembered my previous research for winter preparation and have spent available bee time busily doing what is needed. I promise to revisit your post on correct measures for oxalic dribble nearer the time.
    I recently bought a bulk amount of fondant on your recommendation planning to use some in spring and for next year’s winter prep as it keeps and is easier and less messy to buy than make in my kitchen.
    Living in rainy Yorkshire I will take note to remove the Abelo poly inspection trays as I usually leave them in over winter.
    If you are struggling for a topic to drum up some more site traffic, how about creating a strong production hive using donor brood but managing it so it produces plenty of honey without creating something more likely to swarm? I haven’t found a resource that addresses this balance?
    Thank you
    Jonathan

    Reply
    1. David Post author

      Hello Jonathan

      The Abelo Varroa trays should be much less of a problem than the floors/trays I use. All my floors are homebuilt ‘kewl floors‘ and the Varroa tray fits reasonably tightly, significantly restricting airflow. One of the reasons I dislike the Abelo floors is the gaps around the tray – it prevents sealing the hive when vaporising oxalic acid-containing treatments.

      I’m in the process of revising the OA recipe page which will for the basis of a post in the near future.

      Welcome back!
      David

      Reply
      1. Jonathan

        It just so happens that I am making some underfloor entrance floors to keep me occupied over the winter months. I always seem to need more floors. I haven’t used vapour with the Abelo poly floors, I think it would melt the poly somewhere.
        Also may I thank you for the correx posts, the sheets were dauntingly large when they arrived but soon turned into very useful crown boards, clearer boards, Demaree boards, covers for removed supers and great temporary roofs, especially for overhanging the new Abelo roof to stop any leaks. Probably the cheapest and most versatile beekeeping material I have.
        Bravo!
        Jonathan

        Reply
        1. David Post author

          Hi Jonathan

          Depending upon your vaporiser you can use them with poly floors. I’ve got a Sublimox which just has a small nozzle to deliver the OA. I make a wooden entrance cover with a suitable hole in it and it works OK (though it’s more fiddly than wood and if you do slip or touch the poly it does melt).

          Correx is marvellous stuff. Look out for unwanted “For Sale” signs. Most are made of the stuff and they often just get tossed in ditches or stuck down the side of the garage. They’re often 6mm and make excellent slides for Cloake boards.

          Cloake board

          Cheers
          David

          Reply
  9. Elaine Garry

    Interesting read, as I live on the west coast of Canada, I believe we have similar weather patterns. Fondant, I buy Ambrosia (from Germany, it baffles me some business can’t produce this closer by, as the shipping cost must be atrocious) in any case, I leave it in the plastic it is packaged in and cut a rectangle in the top, so it it gets soft, it can’t and doesn’t dribble down! 👍🏼

    Reply
    1. David Post author

      Hello Elaine

      I invert the fondant so that the open face of the fondant is as close as possible to the bees. If the weather gets cold I want them to continue to take it down, without venturing into the cold space above the cluster. With the exception of this one colony this has always worked well. As I describe above, I’m pretty sure it’s a consequence of the ‘sealed’ hive, so something I’ll hopefully be able to avoid in the future.

      I hate to think what the shipping charges must be for fondant from Germany 🙁

      Enjoy the winter
      David

      Reply
  10. Jo Horsley

    Have you done a post on keeping bees in a bee shed? I am curious on how the bees who get out into the shed on inspection get back in.

    Reply
    1. David Post author

      Hello Jo

      Yes … lots when you use the search fundtion. Inevitably these discuss the evolution of my experience using bee sheds, rather than a single post that summarises everything. If you look under the ‘equipment‘ menu you’ll find a chronological list of posts that are related to bee sheds. Finally, Google and other search engines index this site regularly (and do a better job than me). A search on Google for ‘bee shed window’ turns up one of my first posts as the very first hit of over 14 million …

      Google is your friend

      … and the second hit is one of the most recent posts that provides a good overview.

      Happy reading 😉
      David

      Reply
  11. Ian R

    Hello David

    Enjoyed the article thanks. I was thinking about the differences in mite drop in your 4 colonies. Is there any evidence that Colony 2 had a higher level of capped brood than the other colonies when the treatment was added? If so, when the bees emerged between 14th and 21st September there could have been a large emergence of mites which were then hit by the Apivar. Just a thought.

    Reply
    1. David Post author

      Hello Ian

      The intention was to try and work out what was happening … however, social distancing (I was living 130 miles away) prevented me from monitoring the brood rearing at the same time. I’ve been doing some calculations using BEEHAVE on brood and Varroa and was hoping to make some comparisons between the modelled data and ‘real life’.

      As I say in the post “… that will have to wait until another year.” 🙁

      Cheers
      David

      Reply
  12. Archie McLellan

    I too listened to Luis on that webinar. I was very interested to hear him say, after reciting the usual mantra guidance (about following the instructions about the proper use of VMD products and to use only approved products) that he hoped there was some room for discussion with the VMD on possible reformulation of some of these instructions. (I hope I heard him correctly – but I’m not sure.) It seems to me that the disconnect between what happens in the beekeeping community (as seen in Beekeeping Forum, for instance) and the VMD and NBU positions on these practices, just weakens the argument for strict adherence to the manufacturers’ instructions. I guess the two biggest areas of disagreement are the use of non-approved generic products (like lactic acid) and repeated vaporisations of an oxalic acid product at (say) 5-day intervals. It’s hard to fathom the latter as we got confirmation in that same webinar that there is no risk of tolerance/resistance with repeated use of organic acids in varroa treatments.

    PS Am I the only person that finds something unprofessional about the VMD documents containing product instructions being issued as MS Word files? Surely they know how to save as pdf?

    Reply
    1. David Post author

      Hi Archie

      Yes, the MS Word documents are irritating.

      You did hear Luis correctly. I’ve been invited to join a Scottish Working Party on Varroa (I can’t remember the official title off the top of my head). There is more than a disconnect … there’s a chasm of difference between some practices in use and what is actually allowed. This was exacerbated by the introduction of Api-Bioxal in my view. Although these pages are a personal website, it’s well known that I’m an academic and so cannot promote methods that do not adhere to the VMD rules. That doesn’t mean that there are not better ways to do things. There are.

      However, it’s worth noting that properly following the instructions and using an appropriate treatment at the correct time (of year, and on a hive that is in a suitable state) makes it very easy to successfully manage Varroa levels. I reckon doing so costs <1% of my "profits" per hive, which is a trivial price to pay.

      In my view a bigger problem is actually not the rules, it’s beekeepers looking for a quick fix, a magic bullet to solve all their Varroa problems … without having to follow all that pesky guidance and those restrictive rules. I’m going to write something about this in the depths of winter … and it’s something I cover in detail in my winter talk Rational Varroa management.

      Hopefully sense will prevail. I’m encouraged by the group Luis has invited to join the panel. However, there is still a need for beekeepers to engage properly with the details of livestock management … to minimise the ‘deadstock’.

      Cheers
      David

      Reply

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