Tag Archives: hive

Landing boards

I’ve bought and used a number of Abelo poly hives this season. I’m going to review these once I see how the colonies perform overwinter. However, one of their ‘features’ is an integral landing board that forms part of the removable floor (colonies 1 and 3, facing, below).

Abelo poly National hives ...

Abelo poly National hives …

Landing boards are great. They provide a large flattish or gently sloping ramp that leads to the hive entrance. There’s something mesmerising about watching heavily-laden foragers performing an inelegant ‘tail-down’ crash-landing several inches short of the entrance, righting themselves, and marching purposefully forwards into the gloom of the hive.

During a heavy nectar flow this happens dozens of times a minute, with a strong colony making about 35,000 foraging trips per day. It’s great to rest your elbows on the hive roof, peer over the top and watch hundreds of foragers bringing the nectar back, 40 milligrams at a time.

Integral landing boards and DIY

Mine's bigger than yours

Mine’s bigger than yours

Landing boards must be popular with other beekeepers as well as they regularly feature in commercially available hives. The Abelo implementation is relatively neat, projecting perhaps 5cm from the front face of the hive.

Other variants are rather more in-your-face. The version in the image on the right is on an early variant of a Maisemore’s poly National hive (I think – please correct me if I’m wrong – Matt Harris helpfully corrected me here … they’re Paynes hives). Frankly, I think it looks pretty ghastly, but at least returning foragers could crash-land some distance away and still walk the last few hundred yards unimpeded 😉

If your hives are cedar you can easily add a flat or sloping landing board to the front of the floor. If you’re going to do this use reasonable quality wood – the exposed edge of a strip of plywood tends to delaminate pretty quickly. Alternatively, build something cheap, functional and easily replaceable from Correx.

Thorne's budget hive ...

Thorne’s budget hive …

The bee shed houses up to 6 colonies, each with a simple short ‘tunnel’ ending in a 1-2″ aperture in the vertical shed wall. I’ve built simple Correx landing boards on these and they’ve performed extremely well over the last two years. Each piece of folded Correx is a distinctive colour to aid the bees returning to the correct hive.

Landing boards ...

Landing boards …

If you take advantage of abandoned ‘For Sale’ signs you can get Correx in a wide range of contrasting colours which saves having to spray paint them before use.

Take a stand

Landing boards don’t need to be attached to the hive front or floor. Some of our early research colonies were housed in lovely cedar hives built by Pete Little of Exmoor Bees & Hives. He provided stands with integral sloping landing (‘alighting’) boards. These are great, though they extend the need for compatibility from the hive itself to the stand as well.

Stand and integral landing board

Stand and integral landing board …

Nice, but not needed

Despite the pleasure to be gained from watching bees return to the hive entrance, landing boards aren’t really necessary and they can get in the way.

Feral colonies generally don’t have the benefit (or need) of a nicely sloping landing board. They cope admirably with a simple unadorned hole through the soffit, with nothing more than the painted boards to cling to … upside down. Crevices or holes in trees, or the church tower, probably have ‘grippy’ surfaces that aid arrival, but there’s no evidence they’re selected on any criteria other than the volume and overall location of the potential new ‘home’.

I used to build my preferred floor – the kewl floor with a mouse-proof and wasp-resistant ‘L’ shaped underfloor entrance – with a shallow integral Correx or plywood landing boards.

Original design

However, over time these all got damaged in transit, or I got sick of bees wandering underneath the floor if they landed on the stand, not the landing board. I’ve recently described a modified entrance to these kewl floors, again made from Correx, that is a marked improvement.

Correx landing board ...

Correx landing board …

There’s a very short video on the page describing these modified entrances showing bees landing and entering the hive perfectly well.

Damaged in transit … or in a pile (up)

The main problem with any sort of protruding landing board is that, by definition, it protrudes.

It therefore gets in the way.

It makes strapping hives up during transport more difficult and means the hives don’t stack together quite as neatly. I only move small number of colonies about, so it’s the inconvenience, not the space, that is the issue.

Abelo hives in transit ...

Abelo hives in transit …

Similarly, during the winter or after uniting colonies in the season, spare floors and other pieces of kit need to be neatly stacked out of the way. Protruding landing boards prevents them being placed on the top of the stack (because the roof fouls the landing board) and – in certain orientations – stops stacks being pushed close together.

Stacked boxes

Stacked boxes …

As an aside, you probably don’t want these floors at the bottom of the stack. Firstly, you’ll inevitably need one when putting together a new hive and it’s easiest not to have to remove the entire stack to access the floor. Secondly, unless blocked off with a sheet of polythene or Correx, they’ll allow wasps and bees access to the stack … or even encourage a swarm to move in.

So … over the years landing boards on my hives have evolved or, more accurately, atrophied. They’re now only present on the outside of the bee shed, on purchased poly hives and, in a rather truncated version, at the cavernous mouth of the Thorne’s Everynucs that I favour.

No landing boards here ...

No landing boards here …

Avoiding disaster

Kewl open mesh floor showing L-shaped entrance slot

Kewl floor entrance …

Kewl floors (sometimes called Dartington-inspired floors) have an ‘L’ shaped entrance that I think offers advantages to the colony when defending against wasps (or robbing by nearby colonies) and negates the need for mouse guards. However, the very feature that provides these advantages – the ‘L’ shaped gap about 9mm high – also makes them liable to get blocked with bee corpses during late winter.

During the depths of the winter, with a relatively quiescent colony and winter bees that are only a couple of months old, this isn’t usually a problem. However, as the winter turns to spring and the colony starts to become active again the attrition rate increases. As the weather improves and the winter bees expire the corpses can block the entrance, trapping the remaining colony inside.

Blocked Kewl floor

Blocked Kewl floor …

This is the sort of thing that should only happen once†. Early in the season you go and visit the apiary on an unseasonably warm and calm day. With one exception the colonies look reasonably active. Foragers are returning with pollen and there are bees setting off on orientation flights.

If you listen carefully at the hive with no activity you might be able to hear the bees panicking inside. Splitting the brood box from the floor reveals the scale of the devastation. It’s a distressing sight. If you’re lucky there will be good numbers of flying bees. If you’re unlucky the colony will have already perished or there will be obvious signs of Nosema.

Kewl floor unblocker ...

Kewl floor unblocker …

With reasonably regular visits to the apiary this is a situation that can easily be avoided. Insert a piece of bent wire – I use an old bicycle spoke – in the entrance slot, turn through 90° and drag it across the full width of the entrance. The ‘vertical’ piece of the wire needs to be longer than the depth of the entrance slot on the floor, but not so long that it fouls the bottom of the frames.

† But, do we always learn from our mistakes? I’ve had this happen a couple of times. In both cases the colony was strong going into the winter and on a double brood box. The first time the colony perished, though it’s not actually clear whether they died from being trapped or from a midwinter virus overload. The second time, April 2015 (shown in the hive photo above), the colony survived. When I discovered the blocked entrance there were still lots of flying bees. I swept the floor clean and cleared the entrance, reassembled the hive and left them to it. On checking a couple of days later they were taking in pollen and I found the laying queen, none the worse for wear, at the first full inspection the following week.

 

 

Swienty poly hives

Or, more specifically, their National poly brood boxes. I’ve just invested in some of these to help some of my colonies overwinter. This was prompted by how well colonies housed in Thorne’s Everynuc’s did last winter when compared to full colonies in cedar boxes. I’ll do a wholly unscientific side-by-side test of colonies in cedar or poly brood boxes to see how they compare.

Choices, choices …

There are a number of polystyrene hives now available in the UK, with offerings from many of the major suppliers. I’ve commented on some of the available poly nucs previously. If, like me, you’re wedded to (or stuck with, depending upon your outlook) National size frames then the choice is a bit more restricted, but is increasing year-by-year. Paynes and Maisemore’s have sold their own designs for some time and Abelo has recently introduced one which is receiving favourable reviews. Of these, I believe the first two are at least partially compatible with cedar boxes, whilst the Abelo is advertised as having the same ‘footprint’ as a cedar box. I’ve not owned any of these so can’t comment further.

Not Paradise …

Poly bait hives ...

Poly bait hives …

However, I have owned some Paradise honey/ModernBeekeeping poly National hives for a few years but, despite the quality of the dense poly, have never been happy with the design. The brood boxes are too narrow for the length of the frame top bars and they have an infuriating ‘lip’ or overhang at the bottom of the box. This makes them incompatible with cedar components – for example when expanding a colony up to a double brood box – and means it is almost inevitable that bees with be squidged when re-assembling the hive. I’ve previously illustrated these design issues and now only use these boxes as bait hives or as a last resort. I should add that, as bait hives, they are excellent.

But Swienty

Swienty

Swienty

The other well established company selling National poly hives are Swienty of Denmark. I already have several of their supers – bought secondhand and still going strong – which I mix’n’match with my motley collection of cedar broods, queen excluders, crownboards and roofs, so it was a logical choice to buy Swienty brood boxes as well. I bought mine from C. Wynn Jones who, as usual, delivered them well-packed and very promptly.

The design has been updated in the last couple of years and now includes press-in frame runners. The boxes are supplied flat-packed and can be assembled in minutes. They are bottom bee space, have handles molded into all four faces and are made from dense and strong polystyrene. Importantly, as far as compatibility is concerned, the top and bottom of the boxes are flat and the external dimensions are 18″/46cm square. They are therefore compatible with the homemade crownboards, floors and insulated roofs I use. Due to the thickness of the polystyrene the internal dimensions are slightly smaller than a cedar box. This means that they will only accommodate 10 frames, rather than the usual 11 plus a dummy board.

How thick?

You’ll read descriptions of these boxes being “45 mm” thick (for example on the Solway Bee Supplies and C. Wynne Jones’s sites). They’re not. What it should say is that they’re a maximum of 45 mm thick. The upper and lower edge of the box is either 40 mm or 45 mm thick (on the ends and sides respectively). However, the majority (75% by area) of all four sides of the box is recessed and is only 29mm thick. In contrast, the Everynuc from Thorne’s has 40 mm thick walls. The ‘old style’ Swienty boxes (my supers are stamped Swienty/Denrosa and are at least 5 years old) are 40+ mm throughout, other than the recesses for the handholds.

How heavy?

Swienty National brood boxes weigh about 1.3 kg unpainted. For comparison, a Thorne’s second quality cedar brood box weighs about 3.5 kg. In the overall scheme of things the ~5 lb difference is probably irrelevant when it comes to hefting full boxes about.

Putting them together

There are no assembly instructions provided, though you shouldn’t need them†. Unlike wooden boxes they cannot be assembled incorrectly (famous last words). The key points are:

  • press-fit together ensuring that only vertical pressure is applied
  • make sure all joints are tightly pushed together
  • glue isn’t needed though I usually add a dab of external wood glue
  • push the frame runners in with the shorter part of the L-shaped plastic inserted into the slot in the brood box (not shown)
  • paint them after assembly and before use

It’s worth also noting here that poly hives can be repaired using Gorilla glue and wooden dowels should anything catastrophic happen.

Painting

I’ve previously spray painted poly nucs with external masonry paint. This works well but since I ran out of paint and have got a bit tired of the colour I decided to use a different approach this time. After consulting the friendly and courteous correspondents on the SBAi forum I’ve used Hammerite Garage Door paint. This is a solvent based paint, available in 750 ml tins for ~£13 in a range of colours, including a rich ‘Buckingham Green’ and a rather striking ‘Oxford Blue’. Being solvent based it reacts very slightly with the polystyrene, forming an impervious bond, so shouldn’t flake off as some masonry paints do.

I used a brush to apply two coats, 24 to 48 hours apart. The first coat looks pretty patchy but might have been acceptable if I’d taken a bit more care. The second coat improved things considerably. I finally added hive numbers to the back and front faces (which look almost identical to the sides) to help me orientate the boxes and refer to them in my records. For reference, 2/3rd of a tin is sufficient to do two coats on eight of these broods. The nominal coverage per litre is 8m2.

First impressions last

Pros – Well finished, easy to assemble, strong, dense smooth poly, dimensions and top and bottom edges mean interchangeable with National equipment

Cons – Thinner than expected, slightly wider internally than necessary (lots of lateral movement for the frames), no rebate at the bottom of sides (frames may get propolised in double brood colonies)

Winter? … bring it on 😉

Swienty brood box ...

Swienty brood box …

† The well-known ESBA Apiarist has a post on assembling the old-style Swienty/Denrosa brood boxes. These lack the frame runners the current design has. In the post he describes using varnish to protect the recess where the frame lugs sit, an area that would inevitably get heavily propilised and require scraping clean. This should be less of an issue with the new-style boxes.

In a related posting on the SBAi forum Calluna4u – who is very familiar with these boxes – gives an additional reason for protecting the polystyrene in the frame lug rebate area. Since the poly is thinner here there is the possibility of light getting in – either due to translucence or because the edge of the box isn’t kept obsessively clean. The bees tended to chew this area. Varnishing helps protect the poly. I didn’t use varnish, but did paint this area to reduce any translucence.

 

Bee shed inspections

A brief update on how things have been progressing in the bee shed. This is my first full season keeping colonies full-time within a shed or building though I’ve successfully overwintered mini-nucs in an unheated greenhouse in the past.

Under construction ...

Under construction …

When installed at the end of last season there was almost no need to open the hives, so it’s only this Spring that the pros and cons of the bee shed have begun to be properly understood.

The colonies are completely enclosed with simple tunnels leading to exits on the East/South East face of the shed. All the colonies are housed in standard National cedar boxes or poly nucs. Other than clear perspex insulated crownboards, there is no additional insulation and the shed is not heated. The shed is situated in open parkland with woodland and arable land nearby containing good forage and there is a permanent water supply nearby.

Colony development and Varroa loads

Colonies went through the winter in single National brood boxes, fed with fondant and treated with oxalic acid by vaporisation in September (before moving them to the shed) and in midwinter. The first inspection was conducted in late March. Colonies were building up well and were significantly stronger than colonies headed by sister queens in the same apiary or in my other apiary. Between late February and early May colonies dropped only 3-4 mites in total, with Varroa boards located within pull-out trays in the hive floor. I’m sure I missed a few mites, but doubt it was very many. We’ve recently uncapped a full frame of drone brood – each cell uncapped individually – and found no Varroa present. Mite levels are therefore reassuringly low – for reasons to be discussed in a future post – with no signs of DWV-related disease.

Varroa tray ...

Varroa tray …

Since mid-April colony development has been very good and they are now on double National brood boxes with 2-3 supers. A fourth super went onto one colony on the 25th of May and the stack now nearly reaches the shed roof. A four frame nuc has been split off one colony already to cool it down a little. Quite a bit of developing brood has also been harvested at weekly intervals for our research, usually by simply cutting a big slab out of the middle of a frame. This has probably also held the colonies back a bit and it’s only now I’m starting to plan for swarm prevention/control.

Inspections

Inspections have been easier than expected. These colonies are headed by queens with reasonable genetics (Heinz queens – local mongrels of 57 varieties, reared by me in 2015). The bees are steady on the comb and tend not to fly up at you when the crownboard is lifted. They’re nothing particularly special, but would be considered reasonably placid and non-aggressive.

The colony is gently smoked from outside the shed (through the entrance tunnel) and a small amount is wafted under the crownboard or between the QE and the bottom super. After allowing them to settle the supers and crownboard are removed and placed outside on an overturned roof. The queen excluder and adherent bees are also left standing outside (unless it’s cold when the bees are shaken off into the open hive).

Inspecting the colony is straightforward. Any frames removed to make space are rested on the hive stand. Double brooded colonies are split into two, with one box stood aside on an eke on the roof of an adjacent hive roof. Inevitably, the queenless half of the split tends to get tetchy within a few minutes, so it’s best to deal with them first. When frames need to be shaken free of bees this can be done either over the open hive or, better still, directly into a gap between the frames. If done outside many of the nurse bees on the frame fail to get back to the hive (they’ve probably not been on orientation flights yet).

The smoker is usually stood just outside the shed door … if you keep it in the shed during inspections you can end up being kippered 😎

Flying bees

Perhaps surprisingly, even going through all 22 frames in a double colony, the shed does not fill with a maelstrom of flying bees. Undoubtedly this is partly because they’re reasonably calm colonies. Those that do fly rapidly find the window or open door and make their exit. When I first started doing inspections in the bee shed I’d manually help the stragglers outside after reassembling the hive. It turns out that there’s really no need … almost all the bees quickly vacate the shed by making a beeline ( 😉 ) for the bright lights of the windows or doors.

The great escape ...

The great escape …

Just how quickly the bees leave the shed was emphasised last Sunday when selecting larvae for grafting. I opened and inspected a double brooded colony, found a suitable frame with 24 hour larvae on it and placed it in a two frame nuc for protection. Within 5 minutes I could work without a veil (I react very badly to stings to the face so take particular care over this) without interruption from flying bees.

Weather and temperature

I’m sure that the temperature influences the behaviour of the colonies in the shed. They certainly forage – or perhaps collect water to use fondant or crystallised stores – at lower temperatures than those situated outside. When inspections are conducted on a cold day (say 10-11°C) they are even more steady than usual. However, those that do fly take longer to leave the shed and they can end up clustering in small, rather pathetic, little groups which then need to be scooped up on a hive tool and dropped into the colony. On cool days I don’t leave the supers or QE outside the shed as the bees would rapidly get chilled. Work commitments mean that inspections must be conducted on certain days, so I don’t have the luxury of simply waiting until it’s a bit warmer. Although the shed is unheated the temperature differential between the inside and outside is significant – perhaps 4-8°C – or more if the sun is shining on the window side of the shed. On a warm, sunny day the temperature inside the shed can easily reach the mid-20’s which makes inspections a hot and sweaty activity.

Needless to say, inspections on damp or wet days are much better than on colonies located outside. I avoid days when it’s raining hard, partly for my own comfort to avoid getting wet accessing the apiary, but also because I’d prefer not to force the bees to fly on a really wet day. However, on damp or drizzly days, inspections proceed as normal.

And the bad news is …

Almost everything I’ve written above is positive and my overall initial impression is that the bee shed offers very significant advantages for the sort of beekeeping I need to do. However, there are some drawbacks and design issues that either currently cause problems, or might in the future.

The first is that it’s too small. The shed is 12 x 8 feet and I should have got one at least half as long again. This is largely because it’s also used for equipment storage and has a small table for working on. With four hives I need storage for 8-12 supers, additional brood boxes and spare frames. If I was starting again, knowing what I know now, I’d get an 18 x 10 shed with the intention of housing at least 6 colonies and some additional nucs (by contrast mine will accommodate 4 full colonies and 2 nucs down the sunny side of the shed, with the possibility of 2-3 additional nucs at a squeeze). It’s not only equipment storage that takes up the room … you need considerable room to work as well, with space for turning, stacking and temporary placement of hive parts. Working in the bee shed encourages an efficiency of movement – or causes a lot of collisions – I’d not expected.

Essential storage ...

Essential storage …

Secondly the lighting is – at best – variable. On a sunny morning there’s ample light to see eggs and tiny larvae. However, as the colonies have grown, the added supers restrict the amount of light getting through the windows. On an overcast day, or late in the afternoon, the lighting is pretty hopeless – good enough to see queen cups/cells, good enough to locate the queen, but (particularly on dark frames) too dim to see eggs, small larvae or to check frames for signs of disease. It’s not unusual to have to carry frames outside to inspect them fully. I’m currently investigating 12V LED systems run from a solar panel-charged caravan battery. My only concern is that this might disorientate the bees and slow their exit from the shed during inspections.

Multiple supers ...

Multiple supers …

Thirdly, I should have spent more time designing the hive stands. I made them an inch or so too low which caused some problems with locating the hive entrances centrally in the T&G planks, but was not insurmountable. More problematically, as a consequence of the leg locations it’s difficult to keep the floor clear of hive debris that falls through the OMF. With the Varroa boards in place this isn’t an issue, but when they’re out – which I prefer if there’s a chance of the shed getting very warm – the debris needs to be regularly swept up to keep the shed clean. Some sort of removable debris trays would have been a good addition, but are not easy to fit retrospectively. However, the overall hive stand design – with the legs going through the suspended floor to avoid vibrations – works very well.

Finally, swarm control has yet to be tackled. My preferred simple method is doing a vertical split (or using a Snelgrove board that I’m experimenting with this year) but this requires an upper entrance which, obviously, cannot easily be arranged. One possibility is using the Demaree method of swarm control. Alternatively, it would be straightforward to remove the queen into a nuc and let the colony requeen. Currently I’m trying to postpone the inevitable by removal of some brood, ensuring they have enough space within the brood boxes which I swap (top to bottom, bottom to top) periodically, ensuring they have sufficient space in the supers and keeping a close eye on them. The queens are clipped. If they do swarm they’re likely to end up in a lump outside the hive entrance – the ground is flagged and so they should hopefully be relatively easy to scoop up.

 

Divide and conquer

Tom Seeley (of Honeybee Democracy fame) published an interesting paper in the journal PLoS One recently on “How honey bee colonies survive in the wild: testing the importance of small nests and swarming” – the paper is available as a PDF following this link (Loftus et al., 2016 PLoS One 11:e0150362).

Size matters

Using his normal elegant methodology Seeley formally tested the observed reduction in colony size and increased swarminess (is that a word?) of – feral or otherwise – colonies ‘selected’ to survive without Varroa treatment by simply abandoning them. The hypothesis – based on previous studies and an understanding of the biology of Varroa – was that colonies ‘forced’ to swarm by being confined in small hives would inevitably:

  • lose significant amount of Varroa through the act of swarming
  • experience a brood break so delaying Varroa replication while requeening
  • consequently survive better than large colonies in which pathogen levels inexorably increased to a level that would destroy the colony

Testing the hypothesis

He tested this by establishing adjacent apiaries (so they have the same microclimate) with either small (~40 litres … about the same as a National brood box) or large (~170 litre) volume hives and installing nucs in each which contained similar levels of brood, bees and Varroa. No Varroa control was performed. Those in the small hives were not managed to prevent swarming whereas those in the large hives were – with the caveat that the colony was kept together (i.e. queen cells were destroyed, brood frames were spread and ample supers were added). The study lasted two years, with regular monitoring of the colony strength, Varroa infestation level etc.

High levels of DWV

High levels of DWV …

To cut a long (but nevertheless interesting and worth reading) story short … the results support the original hypothesis. During the first year of the study the colonies developed in a broadly similar manner from transfer of the nuc to the large or small hive in June until the season’s end. However, by the following May the large hived colonies were almost twice as populous as those in the small boxes. This continued until August, with the average adult bee population in the small and large hives being ~10,000 and ~30,000 respectively. During this second season 10/12 small hives swarmed, whereas only 2/12 of the large hived colonies swarmed. In the latter mite levels dramatically increased to >6/100 adult bees (i.e. riddled with the little b’stards – my opinion, Seeley is too polite to comment). For comparison, the picture above has ~100 bees in it, with one visible Varroa, but has lots of overt deformed wing virus disease. In contrast, the small hived colonies – with the exception on one sampling point discussed later – had three to five times fewer mites than seen in the large hived colonies. By the second winter 10/12 large hived colonies had perished whereas only 4/12 small hived colonies had succumbed, and one of these was to a drone laying queen, not disease. Perhaps most tellingly, 7/12 large hived colonies had signs of overt deformed wing virus (DWV) disease – pathetic, tottering newly emerged workers with stunted abdomens and shrivelled wings – whereas none of those in small hives showed obvious disease.

Great … Varroa-tolerant colonies … where can I get some?

A small swarm

A small swarm

So, what does this mean in terms of practical beekeeping? Firstly, it suggests that it is possible to keep honey bee colonies without treatment or intervention. But – and it’s a biggy – the colonies will be too small to collect meaningful amounts of honey and will spend their time and energy swarming instead. 10,000 adult bees does not a colony make, as Aristotle didn’t say. Or at least not a colony that’s of any practical use for the honey-gathering goal of beekeeping. Ted Hooper (“Bees and honey“), and many others, have made the point that one big colony will gather more nectar than two smaller colonies. Secondly, these small colonies will chuck out loads of Varroa-riddled swarms. Seeley has previously demonstrated that swarming colonies lose ~35% of their Varroa load with the bees that leave the colony. Although this clearly benefits the original colony it potentially distributes Varroa-laden bees (and the smorgasbord of viral pathogens that are the real problem) to whichever local beekeeper finally hives them. This explains the need for prompt Varroa treatment of any swarms you might acquire.

On a more positive note this study clearly shows the benefit of a brood break in terms of restricting the replication and amplification of Varroa. Presumably this is primarily due to the 3+ week window with no sealed brood for Varroa to infest, though it may also mean that broodless colonies might get rid of Varroa at a faster rate with no brood present to distract them. It would be interesting to have compared mite levels immediately after swarming and in the subsequent weeks until the new queen starts laying. Randy Oliver has also discussed the benefits of a brood break during empirical development (and computer modelling) of his beekeeping methods for Varroa control. In his forthright manner he explains “Take home message: early splitting knocks the snot out of mite levels“.

Why discuss this if they’re no use for beekeeping … ?

There was one exception to the generally low mite levels in the small hived colonies and that was late summer in the second year when they all exhibited a large spike in Varroa numbers. This was attributed to robbing-out a collapsing, and soon to die-off completely, large hived colony in the adjacent apiary. The two study apiaries were in the same field. This emphasises the points made in earlier posts about the impact of drifting and robbing and the, at least theoretical benefits of, coordinated Varroa control. Of course, ~2 mites per 100 adult bees in the small hived colonies is not really a low number at all. Assuming a colony size of 10,000 adults with 80% of the mites in capped cells the total Varroa load would be ~1000 in the colony, the threshold level above which the NBU consider treatment is required to avoid loss of the colony.

Divide and conquer

The Varroa loss achieved by swarming, coupled with the break in brood rearing, help the colony conquer – or more correctly tolerate – Varroa levels that otherwise rapidly increase and destroy a colony. However, this is neither a practical or acceptable solution to the Varroa problem. ‘Beekeepers’ (an oxymoron surely?) that allow their colonies to swarm indiscriminately both reduce their chance of getting a good honey crop and impose their – potentially Varroa-ridden – swarms on the neighbourhood. This is irresponsible. In contrast, beekeepers who carefully monitor their colonies and use an effective combination of integrated pest management – for example, including an enforced brood break during the ‘June gap’, or a vertical split, perhaps – benefit from large, healthy, honey-laden§ colonies which overwinter better.

§ at least in the good years 😉