Category Archives: Beekeeping

2019 in retrospect

The winter solstice, the shortest day of the year, is tomorrow. It will be a long time until there’s any active beekeeping, but at least the days are getting longer again 🙂 

The queens in your colonies will soon – or may already – be laying again.

What better time to look back over the past season? How did the bees do? How did you do as a beekeeper? What could be done better next time?

Were there any catastrophic errors that really must not be repeated?

Overview of the season

Overall, in my part of Scotland, it was about average.

But that, of course, obscures all sorts of detail.

Spring was warm and swarming started early. I hived my first swarm before the end of April and my last in early July. This is about twice the length of the usual swarming season I’ve come to expect in Scotland. However, it wasn’t all frantic swarm management as there was a prolonged ‘June gap’ during which colonies were much more subdued.

The summer nectar, particularly the lime, was helped by some rain, but the season was effectively over by mid-August. I don’t take my colonies to the heather. Overall, the honey crop was 50-60% that of the (exceptional) 2018 season.

Looking at the yields from different apiaries for spring and summer it’s clear that – despite the warm spring – colonies did less well on the early season nectar (~40% that of 2018). I suspect this is due to their being less oil seed rape (OSR) grown within range of my apiaries. The colonies were strong, but the OSR just wasn’t close enough to be fully exploited..

Over recent years the area of OSR grown has reduced, a trend that is likely to continue.

Winter oil seed rape – the potential is not obvious

The winter rape is already sitting soggily in the fields; I’ve chatted to a couple of the local farmers and will move some hives onto these fields if colonies are strong enough and the weather looks promising.

Bait hives

Every year I’ve been back in Scotland I’ve put a bait hive in the garden.

Every year it has attracted a swarm.

This year – with the extended swarming season – it led to the capture of three swarms in about 10 days. As the June gap ended the weather got quite hot and sultry 1 and the first swarm arrived near the end of that month.

One week after the first swarm arrived there was lots more scout bee activity. There were also quite a few dead or dying bees littering the ground underneath the bait hive. It turned out that these were the walking wounded (or worse) scout bees from two different hives fighting.

Gone but not forgotten

Within 48 hours another swarm arrived and I was fortunate enough to watch it descend.

Incoming!

I moved the hive that evening, placing another bait hive on the same spot. By the following morning there were yet more scout bees checking the entrance and a third swarm – by far the biggest of the three – arrived later that day.

Each was a prime swarm and none were from my own hives which are in the only apiary 2 within a mile of the bait hive.

Watching the scout bees check out a bait hive is always interesting. There’s a fuller account of the observations and lessons learnt – of which there were several – written in the post titled BOGOF (buy one get one free 😉 ).

Swarm prevention

My swarm prevention this year either used the nucleus method or vertical splits (with an occasional Demaree for good measure) for most hives. All prevented the loss of swarms and queen mating went about as well – or badly – as it usually does i.e. never as fast as I’d like, but (eventually) all were successful.

Split board

Split board …

I did miss a couple of swarms. One relocated underneath the OMF of the hive it originated from because the queen was clipped and, having fallen ignominiously to the ground, she just clambered up the hive stand again.

The second swarm was also not lost as I inadvertently trapped the queen on the wrong side of the queen excluder. D’oh! In my defence, I’ve had a rather busy year at work 3 and it’s little short of a miracle that I got any beekeeping – let alone swarm control – done at all.

Mites

Considering the extended June gap, which resulted in a brood break for some colonies, mite levels were appreciably higher this year than last. I think this can largely be attributed to the warm Spring which allowed colonies to build up fast. Several colonies were strong enough to swarm in late April.

I do a limited amount of mite counting during the season but also monitor virus loads in emerging bees in our research colonies. In most colonies these stayed resolutely low and no production colonies needed any mid-season interventions for mite control.

Poly Varroa tray from Thorne's Everynuc with visible mites.

Gotcha! …

Newly-arrived swarms were treated as were some broodless splits. The former because many swarms carry a larger than expected mite population 4 and the latter because it’s an ideal opportunity to target mites as – in the absence of brood – all will be phoretic.

All colonies were treated with Apivar immediately after the summer honey came off. At the same time they were fed copious amount of fondant in preparation for the winter ahead.

In late November most colonies were broodless and were treated with a vaporised OA-containing miticide.

What worked well

In what was a pretty tough year for non-beekeeping reasons even small beekeeping successes have assumed a significance out of all proportion to the effort expended on them.

In my first year or two of beekeeping honey extraction was an unbridled pleasure. As hive numbers increased it because more of a chore. An electric extractor marginally improved things.

However, there was still the never-ending juggling of frames trying to balance the extractor and jiggling of the unbalanced machine as it sashayed across the floor.

Rubber-wheeled castor with brake

Two years ago I purchased some rubber braked wheels to add to the extractor legs.

This year I finally got round to fitting them.

The jiggle-free revolutions were a revelation 🙂

I know some beekeepers who stand their extractors on foam pads. Others who have them bolted to a triangular wooden platform. I can’t imagine either solution works better than these castors, which also make moving the extractor to and from storage much easier.

I changed my hive numbering system this season. I’d previously referred to hives by position or with a number written on the box. This caused some issues with the (sometimes shambolic) way I do my beekeeping.

If the hive moves and it’s numbered by position then its number should change. Manageable, but a bit of a pain.

If the position does not change but they’re expanded from a nuc to a full brood box do they get a new number or retain the old one? A problem if it’s written on the box.

And what happens when you move queens about in the apiary (which we sometimes need to do for work)?

Numbers for hives and queens

Numbers for hives and queens

All hives and queens were assigned a number – small red discs for the queen and big, bold numbers for the box. They stay with the colony or the queen … and the records 😉

This has worked very well. As colonies expand the numbers move, if queens are moved I know from and to where (and keep a separate record of queen performance). When colonies are united the queenless component loses both the queen number and the colony number.

The numbering has been a great success. The numbers themselves less so. Most of the red discs have faded very badly and a few of the hive numbers have cracked and/or blown away.

Numbered nuc and production colonies.

Never mind … the system works as intended and it has significantly improved my record keeping. I now know which hive and queen I’m referring to 😉

The Apiarist in 2019

I might squeeze in a more thorough overview of funny search terms and page accesses before the New Year. Briefly … there are significantly more subscribers and an increase of ~20% in overall page reads.

This year marks the sixth full season of The Apiarist which still surprises me. There still seem to be things to write about. Post length continues to increase, though the overall number of posts remain almost exactly one a week. Amazingly I’ve written nearly 95,000 words this year.

Words, words, words …

We had some server issues but most of these appear to have been resolved. Spam remains a problem and the machine auto-filters several hundred messages a day to keep my inbox only unmanageably overflowing. It has meant I’ve had to add some “I am not a robot” CAPTCHA trickery to the contact and/or comment forms. I’m aware that this has caused some problems making contact but can’t find an alternative solution that doesn’t swamp me in adverts for fake sunglasses, Bitcoins or Russian brides.

I live in Scotland and have no use for any of these things 😉 5

The year ahead

There are three main items on the ‘to do’ list for 2020 6.

The first is to start queen rearing again. Pressure of work has prevented this from happening over the last couple of seasons and I’m missing both the huge satisfaction it brings and the improved control over stock improvement. I’ve done lots of queen rearing in the past, but work has muscled its way in to too many weekends and evenings recently 7.

3 day old QCs ...

3 day old QCs …

I now have some perfectly adequate bees.

Actually, although they’re far from ‘perfect’ they are also far better than ‘adequate’.

I’ve got a couple of lines that have too much chalkbrood and almost all of them are less stable on the comb than I’d like. They don’t fall in wriggling gloops off the corner of the frame as some do, but they’re more active than I’d prefer. It’s a trait that has crept into some stocks over the last couple of years and I need to try and get rid of it.

The second is to provide better information on the provenance of my honey to potential and actual purchasers. There’s increasing interest in sourcing high quality local food and, as I’ve discussed recently on honey pricing, we should be aiming to provide a premium product (at a premium price 😉 ). The public are also increasingly aware that some of the major supermarkets have been reported to be selling adulterated honey. Providing details of the batch, the apiary and the area in which it was produced should help define it as a quality local product.

And generate repeat business.

Local honey

Finally, I’m planting up a new apiary on the west coast with dozens of pollen-bearing trees before I start beekeeping there. This has been a long and protracted process as it has involved clearing large areas of invasive rhododendron. The first 125+ native trees go in this winter – a mix of alder, loads of willow, hazel, blackthorn and wild cherry. More will follow if I manage to stop the deer eating them all.

Only another few acres of rhododendron to clear 🙁

The new apiary is in a Varroa-free region so I will not be moving my current bees there, but instead sourcing them from other areas fortunate enough to be mite-free. This is a long-term project.

Bee shed #3 … bigger and better.

The trees will need a few years to mature but the bee shed (bigger than all that have gone before 🙂 ) foundations are finished and the shed will be assembled sometime in March.

Holibobs

The holiday period is almost here. Many beekeepers will be thinking about fondant top-ups and oxalic acid mite treatment. I’ve done the latter already and – if your colonies are also broodless – hope you’ve done the same. All my hives remain reassuringly heavy but as the weather warms and brood rearing gears up I’ll have some fondant ready ‘just in case’.

I’ve covered last-minute beekeeping gifts in previous years. I think the (digital edition) American Bee Journal remains good value and provides a different perspective for UK beekeepers of what happens in the US.

And with that I’ll pour another glass of mead red wine 8 and wish you all Happy Christmas/Holidays (delete as appropriate).

David


 

Rinse and repeat

Midwinter mite treatment is no substitute for a properly applied late summer treatment that protects your all important winter bees. However, you also need to control mites in the winter or there is a good chance their numbers will reach damaging levels the following season 1.

Mid September

Late summer treatment and no winter treatment – mite levels in red.

OA (oxalic acid-containing) treatments are the ones to use in midwinter (e.g. Api-Bioxal). These can be trickled in syrup onto each seam of bees or they can be vaporised (sublimated), effectively coating everything in the hive with a very fine dusting of crystals.

Trickling damages open brood whereas sublimation is exceedingly well-tolerated by the colony.

If you are certain the colony is broodless then trickling is faster 2 and – because you don’t need power or any more PPE 3 than a pair of gloves – much easier.

If the ambient temperature is consistently below ~6°C and I know the colony is broodless I usually trickle. If the temperature is higher and/or I’m uncertain about whether there is brood present I usually vaporise.

I watch the weather and treat after the first prolonged cold spell of the winter.

Experience over the last few years suggests this is when colonies are most likely to be broodless.

Most likely is not the same as certain 🙁

Count the corpses

After treating I closely monitor the mite drop over several days. I use white Correx Varroa trays that slide underneath the open mesh of my kewl floors.

Easy counting ...

Easy counting …

I don’t count the mites every day, but I do try and count the day after treatment and 2-4 days later. I record the mite drop per hive and, over time, look for two things:

  1. The cumulative mite drop. This indicates the original infestation level of the hive. Usually it’s in the range 10-75 mites (total) for my colonies in midwinter, but – as you’ll see – it can be much higher.
  2. The speed with which the daily mite drop falls to a low single-digit average. OA treatment is very effective at killing phoretic mites. If there’s a continuing high level of mite drop it suggests that more are getting exposed over time.

In my experience, vaporised OA often results in a greater mite drop 24-48 hours post-treatment rather than in the first 24 hours 4. After that I expect (hope) the daily mite drop tails off very quickly.

Vaporised OA remains effective in the hive for several days. Randy Oliver reports studies by Radetzki who claims it remains effective for up to three weeks. I think this is an overestimate but I’m sure it continues working well for four to five days.

OA, whether vaporised or trickled, on broodless colonies is 90-95% effective i.e. if there were 100 mites in the colony you should expect as few as 5 remain after treatment.

Four to five days after the initial treatment I eyeball the numbers across all the hives in an apiary and look at the profile of the mite drop.

Mite drop profiles

I couldn’t think of a better term for this. Essentially, it’s the shape of a graph of mites dropped per day after treatment.

I don’t usually draw the graph – I have a life – but I do look carefully at the numbers.

Here are a couple of sketched graphs showing what I mean. Days are on the horizontal (X) axis, dead mites per day are on the vertical (Y) axis. Treatment applied on day 0. No count (yet) on day 6.

Mite drop profile – this is what you want

In the graph above there are high(er) levels of dropped mites on the first day or two after treatment, but levels thereafter drop to a basal level of perhaps 1-4 mites per day.

Each time I count the mites I clean the Varroa tray (the rinse in the title of the post).

Assuming the day 5 mite drop is very low, the profile above is what I’m looking for. It shows that treatment has worked and no repeat is necessary.

The profile below is much less promising 5.

Mite drop profile – this suggests additional treatment is needed

In this graph (above) the mite drop remains high every day after treatment. Sometimes they even increase over time.

If you assume treatment is equally effective – say 90%+ – on the five days after treatment 6 this must mean that there are mites being killed on days 4 and 5 that were not exposed to treatment on the earlier days.

How can this be?

The most likely explanation is that the colony had some sealed brood that has emerged in the days following treatment, exposing previously ‘hidden’ mites to the miticide.

It’s good that they’ve perished, but are there more hiding? How do you tell?

Enough of my hand drawn idealised graphs with no real numbers … what about some actual data?

Real world data

The graph below shows data for seven colonies in a single apiary. All were treated with Apivar in late summer. All were treated with a vaporised oxalic acid-containing treatment on the 28th of November. 

Mite drop profiles – real world data

I counted the mite drops on the 29th (T+1), the 2nd (T+4) and 3rd (T+5). The figures for 30th to the 2nd were averaged, which is why the bars are all the same height.

  • Colonies 3 and 6 had very low mite levels. Though not the lowest in the apiary 🙂
  • Colonies 2 and 7 had pretty good mite drop profiles, with low single-digit numbers on day T+5. None of these four colonies (2, 3, 6, 7) need treating again.
  • Colonies 1 and 5 have high mite levels 7 and – despite the pretty good levels on T+5 in colony 1 – were both re-treated.
  • Colony 4 was also treated again as the profile was flat and I suspected they had low levels of mites but were rearing brood..

And repeat

Note: The instructions for Api-Bioxal specifically state that the maximal dose of 2.3g/hive should be made in a single administrations with only one treatment per yearPrior to the VMD licensing and approval of Api-Bioxal there was effectively tacit approval for beekeepers to use unadulterated oxalic acid by trickling or vaporisation, without any particular limitations on frequency of usage.

It’s worth stressing that you should not repeat oxalic acid trickling 8.

Here is some real data for repeat treatments of another colony in the same apiary.

Repeat treatment for brood-rearing colony

The average mite drop per day over the first 5 days was ~60. This justified an additional treatment. Over the next 6 days 9 the average drop was ~20. I considered a third application was needed after which the mite drop per day was in the low single digits.

And again

Repeated treatment is needed if there is sealed brood in the colony.

The likelihood is that two additional treatments will be required.

Why two?

Here’s a reminder of the development cycle of the Varroa mite in developing worker or drone brood.

Repeated oxalic acid vaporisation treatment regime.

Worker brood occupies capped cells for 12 days (days 10 – 21 of development, shown above). Vaporised oxalic acid-containing treatments show a drop in efficacy after 4-5 days 10.

Therefore, to cover a complete cycle of capped brood, you need 3 x 5 day treatments to be sure no mites emerge without them being greeted with a lethal dose of something really, really unpleasant 😉

There should be no drone brood in your winter hives 11 but, if there was, 3 x 5 day treatments should just be enough to cover the complete cycle of capped drone brood as well. However, a fourth treatment might be needed.

Note (again): The instructions for Api-Bioxal specifically state that the maximal dose of 2.3g/hive should be made in a single administrations with only one treatment per year

Not all hives are equal

There are 15 hives in the apiary containing the bee shed. Colony 1 had just about the highest mite levels. However, as shown in one of the graphs above, adjacent colonies can have markedly different mite levels.

There is no clear correlation between mite drop after treatment and colony size. Colony 1 is a double brood monster, but the others in the bee shed are all single brood 10 and 11 frame Nationals 12.

Some colonies need repeated treatment, others did not.

To maximise efficient treatment and minimise unnecessary miticide usage it is necessary to monitor all the colonies.

It’s also worth noting that monitoring only a single hive in an apiary may be misleading; compare colonies 1 and 6 above in the graph of real data from the bee shed.

This monitoring takes just a few minutes. I usually do it after work. In the bee shed this is easy as I now have LED lighting and it’s nice and dry.

Easy conditions to count mites

In my out apiaries I have to do it by headtorch … under an umbrella if it’s raining 🙁

Checking mite drop by torchlight

That’s the last job of the winter completed … time now to review the season just gone and plan for next year.


Colophon

Rinse and repeat

Rinse and repeat is a truncation of instructions often found on the side of shampoo bottles – Lather, rinse and repeat. Other than potentially resulting in an endless loop of hair washing, it also means that a process is (or needs to be) repeated.

In The Plagiarist by Benjamin Cheever, a marketing executive becomes an industry legend by adding one word – REPEAT – to shampoo bottles. He doubles sales overnight.

For Varroa treatment the instructions should be amended to Repeat if necessary … and note again the instructions on Api-Bioxal which, at the time of writing, is the only oxalic-acid containing VMD approved miticide that can be administered by vaporisation.

 

More local bee goodness?

Before the wind-down to the end of the year and the inevitable review of the season I thought I’d write a final post apparently supporting the benefits of local bees. This is based on a recently published paper from the USA 1 that tests whether local bees perform better than non-local stocks.

However, in my view the study is incomplete and – whilst broadly supportive – needs further work before it can really be seen as an example of better performing local bees. I suspect there’s actually a different explanation for their results … that also demonstrates the benefits of local bees.

This is a follow-up to a post three weeks ago that provided evidence that:

  1. Colonies derived from different geographic regions show physiological adaptations (presumably reflecting underlying genetic differences) that seem pretty logical e.g. bees from Saskatchewan express more proteins involved in heat production, whereas Hawaiian bees show higher levels of protein turnover (which would make sense if they had evolved locally to have high metabolic rates).
  2. In a study by Büchler, European colonies survived better overwinter in their local environment; a fact subsequently attributed to the colonies being stronger going into the winter. In turn, this agrees with a recent study that clearly demonstrates the correlation between overwintering success and colony strength.

I suggest re-reading 2 that post as I’m going to try and avoid too much repetition here.

Strong colonies

Strong colonies overwinter better and – if you’re interested in that sort of thing – are much more likely to generate a profit for your honey sales.

So how can you ensure strong colonies at the end of the season?

What influences colony strength?

One thing is colony health. A healthy colony is much more likely to be a strong colony.

In the ambitious 600-colony Büchler study in Europe they didn’t do any disease management. The colonies were monitored over ~2.5 years during which time 84% of colonies perished, at least half due to the ravages of Varroa.

Clearly this is not sustainable beekeeping and doesn’t properly reflect standard beekeeping practices.

Study details

The recent Burnham study makes a nice comparison to the Büchler study.

It was conducted in New York State using 40 balanced 3 colonies requeened in late May.

Queens were sourced from California (~4000 km west) or Vermont (~200km east in the neighbouring state, and therefore considered ‘local’) and colonies were assigned queens randomly.

Unlike some previous studies the authors did not evidence the genetic differences between queens.

A local queen

A local queen

However, the queens looked dissimilar and the stocks were sourced from colonies established in California or Vermont for at least 10-15 generations. I think we can be reasonably confident that the queens were sufficiently distinct to be relevant for the tests being conducted.

Colonies were maintained using standard beekeeping practices, Varroa levels were managed using formic acid (MAQS for European readers) and the colony weight and productivity (frames of bees) was quantified, as was the pathogen load.

In contrast to the Büchler study, Burnham and colleagues only followed colonies over one beekeeping summer season. This was not a test of overwintering survival, but mid-season development.

Results

The take-home message is that colonies headed by the ‘local’ Vermont queens did better. The colonies got heavier faster and brood levels built up better.

Bigger, faster, stronger …

It’s notable that colony weight built up before any brood would have emerged from the new queen (upper panel) and that brood level in colonies headed by the local queen recovered much better after formic acid treatment (arrow in lower panel).

Nosema levels

However, Nosema levels were significantly different (above) as were the levels of Israeli Acute Paralysis Virus (IAPV; below).

Virus loads (DWV, BQCV and IAPV)

There were no significant differences in the Varroa loads before or after treatment (not shown), or in the levels of DWV or Black Queen Cell Virus (BQCV).

Taken together – bigger, heavier, stronger colonies and lower pathogen loads (at least of some pathogens) – seems good evidence to support the contention that local bees are beneficial.

The benefits are precisely what you want for good overwintering – strong, healthy colonies.

That’s a slam-dunk then?

Case proven?

No.

IAPV is a virus rarely detected in the UK. It causes persistent and systemic infections in honey bees and can be found in every caste (drones, workers, queens) and at every stage of the life cycle.

As IAPV is detectable in eggs and larvae – neither of which are Varroa-exposed – it is assumed to be vertically transmitted from the queen. IAPV is also found in the ovaries of the queen, which is additional evidence for vertical transmission.

At the first timepoint (12 days post requeening) the levels of IAPV are different between the two colony types, but not significantly so. However, by 40 days (T2) the levels are very different. At this later timepoint all the bees in the colony will be have come from the introduced queen.

The authors explain the differences in IAPV levels in terms of local bees being more resistant to ‘local’ pathogens … in much the same way that Pizarro’s 168 conquistadors, being more resistant to smallpox, defeated the might of the Inca Empire with the help of the virus diseases they inadvertently introduced to Peru.

I suspect there’s another explanation.

Perhaps the Californian queens were IAPV infected from the outset?

If this was the case they could introduce a new and virulent strain of IAPV to the research colonies and – over time – the levels would increase as more and more workers in the colony were derived from the new queen. IAPV is present in ~20% of US colonies so it seems perfectly reasonable to suggest it might have been largely absent from the Vermont queens and the test colonies, but present in the queens introduced from California.

How should they have tested that?

The obvious thing to do would be to characterise the IAPV present in the colony. IAPV shows geographic variation across the USA. If the predominant virus was of Californian origin it would suggest it was brought in with the queen. This is a relatively easy test to conduct … a sort of 23andme to determine bee virus provenance.

Alternatively, though less conclusively, you could do the experiment the other way round … ship Vermont queens to California and compare their performance with colonies headed by Californian queens on their own territory. If the Californian queens again performed less well it undermines the ‘local bees do better’ argument and suggests another explanation should be sought.

Nosema is sexually transmitted but it is not vertically transmitted, so the same arguments cannot be made there. Why the Nosema levels drop so convincingly in colonies headed by the local queens is unclear. Nosema was present at the start of the study and was lost over time in the stronger colonies headed by the local queens.

One possibility of course is that the stronger colonies were better fed – more workers, more foragers, more pollen, more nectar. Improved diet leads to a more active and effective immune system and an increased ability to combat pathogens. Simplistic certainly, but it is known that diet influences pathogen resistance and colony performance.

So what does this paper show?

I suspect it doesn’t directly show what the authors claim (in the title) … that local queens head colonies with lower pathogen levels.

This largely reflects the lack of proper or complete controls. However, it does not mean that local bees are not better.

More than anything I think this paper demonstrates the impact queen quality has on colony performance.

Perhaps the Vermont-sourced queens were just better queens. Local certainly (on a USA scale definition of the word local), but not better because they were local, just better because they were better.

However, if my interpretation of the source of the IAPV is correct i.e. introduced from the Californian queens, I think the paper indirectly demonstrates one of the most compelling reasons why local bees are preferable.

If they’re local – your apiary, your neighbours, someone in your association – there is little chance they will be bringing with them some unwanted baggage in the form of an undetected exotic pathogen.

Or a more virulent strain of one already circulating relatively benignly.

Extensive bee movements, whether of queens, packages or full colonies, risks spreading parasites and pathogens.

There is compelling evidence that hosts and pathogens co-evolve to reduce the pathogenicity of the interaction. Naive hosts are always more susceptible to introduced pathogens, or novel strains of pre-existing pathogens. After all, look what happened to the Peruvian Inca when they met the measles- and smallpox-ridden conquistadors.

So, when thinking about the claims being made by bee importers (or, for that matter, strong advocates of local bee breeding), it’s worth considering all of the factors at play – queen quality per se, genetic adaptation of the queen to the local environment and the potential for the introduction of novel pathogens with introduced non-local stock.

And that’s before you also consider the benefits to your beekeeping of being self-sufficient and not reliant on others to produce your stocks.

I never said it was simple 😉


 

Midwinter, no; mites, yes

There’s a certain irony that the more conscientious you are in protecting your winter bees from the ravages of Varroa in late summer, the more necessary it is to apply a miticide in the winter.

Winter bees are the ones that are in your hives now 1.

They have a very different physiology to the midsummer foragers that fill your supers with nectar. Winter bees have low levels of juvenile hormone and high levels of vitellogenin. They are long-lived – up to 8 months – and they form an efficient thermoregulating cluster when the external temperature plummets.

Winter bees production

In the temperate northern hemisphere, winter bees are reared from late summer/early autumn onwards. The combination of reductions in the photoperiod (day length), temperature and forage availability triggers changes in brood and forager pheromones.

Factors that influence winter bee production

Together these induce the production of winter bees.

For more details see Overwintering honey bees: biology and management by Döke et al., (2010).

Day length reduces predictably as summer changes to autumn. In contrast, temperature and forage availability (which itself is influenced by temperature and rainfall … and day length) are much more variable (so less predictable).

All of which means that you cannot be sure when the winter bees are produced.

If there’s an “Indian summer“, with warm temperatures stretching into late October, the bees will be out working the ivy and rearing good amounts of brood late into the year. The busy foragers and high(er) levels of brood pheromone will then delay the production of winter bees.

Conversely, low temperatures and early frosts reduce foraging and brood production, so bringing forward winter bee production.

It’s an inexact science.

You cannot be sure when the winter bees will be produced, but you can be sure that they will be reared.

Protect your winter bees

And if they are being reared, you must protect them from Varroa and the viral payload it delivers to developing pupae. Most important of these viruses is deformed wing virus (DWV).

Worker bee with DWV symptoms

Worker bee with DWV symptoms

Aside from “doing what it says on the tin” i.e. causing wing deformities and other developmental defects in some brood, DWV also reduces the longevity of winter bees.

And that’s a problem.

If they die sooner than they should they cannot help in thermoregulating the winter cluster.

And that results in the cluster having to work harder to keep warm as it gets smaller … and smaller … and smaller …

Until it’s so small it cannot reach its food reserves (isolation starvation) or freezes to death 2.

So, to protect your winter bees, you need to treat with an appropriate miticide in late summer. This reduces the mite load in the hive by up to 95% and so gives the winter bees a very good chance of leading a long and happy life 😉

Time of treatment and mite numbers

Time of treatment and mite numbers

I discussed this in excruciating detail in 2016 in a post titled When to treat?.

The figure above was taken from that post and is described more fully there. The arrow indicates when winter bees are produced and the variously coloured solid lines indicate mite numbers when treated in mid-July to mid-November.

The earlier you treat (indicated by the sudden drop in the mite count) the lower the peak mite numbers when the winter bees are being reared.

Note that the mite numbers indicated on the right hand vertical axis are not ‘real’ figures. They depend on the number present at the start of the year. In the figure above I “primed” the in silico modelled colony with just 20 mites. This will become very important in a few paragraphs.

Late season brood rearing

Compare the blue line (mid-August treatment) with the cyan line 3 (mid-October treatment) in the figure above.

The mid-October treatment really hammers the mite number down and they remain low until the end of the year 4.

The reason the mite numbers remain low after a mid-October treatment is that there is little or no brood being reared in the colony during this period.

Mites need brood, and specifically sealed brood, to reproduce on.

In the absence of brood the mites ‘colony surf‘, riding around as phoretic mites on nurse bees (or any bees if there aren’t the nurse bees they prefer).

And that late season brood rearing is the reason the end-of-year mite number for the colony treated in mid-August (the blue line) remains significantly higher.

Mites that survive the miticide in August simply carry on with their sordid little destructive lives, infesting the ample brood available (which could even include some highly mite-attractive and productive drone brood) and reproducing busily.

So, the earlier you treat, the more mites remain in the hive at the end of the year.

Weird, but true.

Early season brood rearing

The winter bees don’t ‘just’ get the colony through the winter.

As the day length increases and the temperature rises the colony starts rearing brood again. Depending upon your latitude it might never stop, but the rate at which it rears brood certainly increases in early spring.

Or, more correctly, in mid- to late-winter.

And it’s the winter bees that do this brood rearing. As Grozinger and colleagues state Once brood rearing re-initiates in late winter/early spring, the division of labor resumes among overwintered worker bees.”

Some winter bees revert to nurse bee activity, to rear the next generation of bees.

And this is another reason why strong colonies overwinter better … not because they (also) survive the cold better 5, but because there are more bees available to take on these brood rearing activities.

Strong, healthy colonies build up better in early spring.

Colonies that are weak in spring and stagger through the first few months of the year, never getting close to swarming, are of little use for honey production, more likely to get robbed out and may not build up enough for the following winter.

Midwinter mite treatments

Which brings us back to the need for miticide treatment in midwinter.

The BEEHAVE modelled colony shown in the graph above was ‘primed’ at the beginning of the season with 20 mites. These reproduced and generated almost 800 mites over the next 10-11 months.

What do you think would happen if you start the year with 200 mites, rather than 20?

Like the 200 remaining at the year end when you treat in mid-August?

Lots of mites … probably approaching 8000 … that’s almost as many mites as bees by the end of the season.

So, one reason to treat in the middle of winter is to reduce mite levels later in the season. The smaller the number you start with, the less you have later.

Vapour leaks out ...

Vaporisation … oxalic acid vapour leaks out …

But at the beginning of the season these elevated levels of mites could cause problems. High levels of mites and low levels of brood is not a good mix.

There’s the potential for those tiny patches of brood to become mite-infested very early in the season … this helps the mites but hinders the bees.

Logically, the more mites present at the start of brood rearing, the more likely it is that colony build up will be retarded.

So that’s two reasons to treat with miticides – usually an oxalic-acid containing treatment – in midwinter.

Midwinter? Or earlier?

When does the colony start brood rearing again in earnest?

This is important as the ‘midwinter’ treatment should be timed for a period before this when the colony is broodless. This is to ensure that all the mites are phoretic and ‘easy to reach’ with a well-timed dribble of Api-Bioxal.

In studies over 30 years ago Seeley and Visscher demonstrated that colonies have to start brood rearing in midwinter to build up enough to have the opportunity to swarm in late spring. These were colonies in cold climates, but the conditions – and season length – aren’t dramatically different to much of the UK.

Low temperatures regularly extend into January or February. The temperature is also variable year on year. It therefore seems (to me) that the most likely trigger for new brood rearing is increasing day length 6.

The apiary in winter ...

The apiary in winter …

I therefore assume that colonies may well be rearing brood very soon after the winter solstice.

I’m also aware that my colonies are almost always broodless earlier in the winter … or even what is still technically late autumn.

This is from experience of both direct (opening hives) or indirect (fresh brood mappings on the Varroa tray) observation.

Hence the “Midwinter, no” title of this post.

Don’t delay

I therefore treat with a dribbled or vaporised oxalic acid-containing miticide in late November or early December. In 2016 and 2017 it was the first week in December. Last year it was a week  later because we had heavy snow.

This year it was today … the 28th of November. With another apiary destined for treatment this weekend.

If colonies are broodless there is nothing to be gained by delaying treatment until later in the winter.

Most beekeepers treat between Christmas and New Year. It’s convenient. They’re probably on holiday and it is a good excuse to escape the family/mince pies/rubbish on the TV (delete as appropriate).

But it might be too late … don’t delay.

If colonies are broodless treat them now.

If you don’t and they start rearing brood the mites will hide away and be unreachable … but their daughters and granddaughters will cause you and your bees problems later in the season.

Finally, it’s worth noting that there’s no need to coordinate winter treatments. The bees aren’t flying and the possibility of mites being transferred – through robbing or drifting – from treated to untreated colonies is minimal.


 

Bee bombs

The last couple of posts on overwintering survival and local bees have been heavy going 1. So, rather than more of the same, here’s something that is both informative and entertaining 2.

Though it maybe wasn’t at the time.

Six-legged soldiers

I’m currently enjoying reading Six-legged soldiers by Jeffrey A. Lockwood. This is an account of the many and devious applications man has found for employing insects in warfare. Whilst the topic certainly isn’t ‘laugh out loud’ entertaining, the book is written in an engaging style with plenty of graphic descriptions, ample Biblical and historical references, and enough wriggly, stinging, aggressive insects to make “I’m a celebrity, get me out of here!” 3 appear like a walk in the park.

As a beekeeper I’m pleased to see that bees feature significantly in the book.

And as a beekeeper who appreciates the importance of the integrity of the colony to bee survival I also found it a little distressing.

But as a source of all sorts of stories for friends and families over the forthcoming holiday season it probably cannot be beaten.

It’s pretty good on mosquitos as well …

Bombus away

The genus Bombus includes lots of the well known bumble bees e.g. Bombus terrestris (Buff tailed), B. pascuorum (Common carder) and B. hypnorum (Tree) . The generic name Bombus is derived etymologically from the Latin word bombus which means buzzing i.e. the noise a bee makes when it flies.

Bombus lucorum

Etymologically, the word bomb, has a similar origin – via bombe in French, bomba in Spanish, bombo and then the Latin bombus.

Boom also has a similar origin.

But that’s not the only link between bees and bombs.

Mushroom shaped clouds

Have you ever seen anyone drop a full brood box?

It is an amazing sight and one best appreciated from a distance and when wearing a full beesuit.

Bees do not appreciate being knocked, shocked or jarred. When I transport hives between apiaries I always give them several minutes to settle before removing the entrance block. If you don’t they tend to boil out the front spoiling for a fight.

So you can imagine that dropping a brood box from waist height achieves – simultaneously – the sudden jarring of the colony and the release of the bees.

Not so much ‘shock and awe‘ as shock and aargh!

The mushroom-shaped cloud of bees that are released are distinctly agitated.

In the absence of a beesuit you’re likely to get hammered.

Even with a beesuit there can be some uncomfortable moments.

And, since soldiers don’t routinely go into battle wearing camouflage BBwear battledress with an inbuilt fencing-style veil, this neatly brings us to using bees as weapons.

Package bees

These days a ‘package’ is one way to buy bees to start a colony.

But as a weapon, a colony of bees isn’t much use until it’s actually in something.

How do you carry them? How do you use them as a projectile?

Well, man is nothing if not ingenious when it comes to weapons development.

The Tiv people of Nigeria used a specially shaped horn, loaded with angry bees (presumably not so much Africanized as African 😯 ). In the heat of battle these would be fired at the opposition, with the horn-shape ensuring the bees both reached the enemy and were kept at a distance from friendly forces 4.

But then, 9000 years ago, pottery containers started to be used for beekeeping … and it got a whole lot easier to move the bee bombs to the front line and drop them on the opposition.

A big, beautiful wall

A wall seems like an obvious way to defend yourself.

The enemy have to knock the wall down, or go over or under the wall.

And if they choose to tunnel under the wall then they’re going to be less than enthusiastic if the tunnel is filled with bees.

Which is what happened in 908 when the Scandinavians laid siege to Chester. The city’s fortifications were impenetrable, so they tunnelled underneath them. The siege was ended when all the city’s beehives were dumped into the tunnel.

Chester City walls. Originally built in ~100 AD by the Romans.

The Scandinavians appear not to have learnt their lesson as they were again repelled by bees while storming the walled city of Kissingen (Germany) during the Thirty Years War (1618-48). In this instance the bees were dropped from a height onto the Swedish forces.

The troops were heavily armed and armoured, and were unfazed.

Their horses were not.

The siege collapsed as the cavalry mounts were driven into a frenzy by the bees. Even now, most beekeepers are aware that bees and horses don’t mix well.

Again in the 1600’s, the besieged nuns of Wuppertal (Germany) knocked over all the hives in their apiaries before – wisely – hiding indoors. The maelstrom of bees drove the marauding soldiers away and the town was subsequently renamed Beyenberg (‘bee town’).

Bee boles

A bee bole is a recess in a wall 5 designed to house a hive of bees, which – in the days when they were constructed – was likely a skep. Many castles and fortified town walls have bee boles built into them.

How convenient.

What could be easier than to drop these on the marauding troops trying to scale the ramparts or storm the drawbridge?

Bee boles in Kellie Castle, Fife, Scotland

As an aside, IBRA (The International Bee Research Association) maintain the comprehensive Bee Boles Register which is well worth searching if you are interested in historical beekeeping (or early bomb design).

Avoiding friendly fire

You’ll notice that a lot of these bees were being used in relatively close combat situations.

Having witnessed a brood box being dropped, I can assure you that bees are rather indiscriminate after a “dropped from a great height onto a hard surface” experience.

Far better to use the container housing the bees as a projectile, launching them at the opposition from a safe distance.

Safe in terms of contact with the enemy … and the bees 😉

The Greeks and subsequently the Romans developed and perfected the siege engine, capable of launching all sorts of things up and over defensive walls.

Including beehives.

Illustration of a ballista being loaded and drawn – note BBwear ‘Corinthian helmet’ style beesuit and veil.

The Greek ballista and the Roman onager were torsion powered siege engines developed between 400 BC and 350 AD. Both were capable of firing stones, often wrapped in combustible material set alight, with smaller later models also used as battlefield weapons firing projectiles 500 – 1000 yards.

They’d have barely broken a sweat firing one or more skeps at the enemy.

The Romans were so keen on bee bombs that there was a documented decline in hive numbers during the late Roman Empire.

And this enthusiasm continued … as did the demand for hives to hurl.

By the 14th Century those dastardly weapons designers had developed a windmill-like device capable of launching hive after hive from the end of its rapidly rotating arms.

Bees will not fly over water

But they will in a skep catapulted from a ship.

As the army developed entomological weaponry the navy exploited it.

As early as 330 BC pottery hives were being thrown at enemy ships during naval battles. Cannons and cannonballs eventually superseded 20,000 A. mellifera ligustica in a skep, but there is well-documented use of bees in naval warfare until at least the 1600’s.

Bees would therefore have been carried by warships for hundreds of years. It’s not documented how the colonies were managed or maintained. Perhaps they only fought local battles? However, since that rather defeats the purpose of a highly mobile navy it can be assumed that bees were probably transported long distances by sea … bringing a whole new meaning to the term migratory beekeeping.

Gunpowder and bees

Eventually the development of modern weaponry overtook the use of bees and beehives. Fortunately we don’t have to discuss the aerodynamic benefits of cedar vs. poly hives 6.

Gunpowder and explosives made the Gatling gun-like skep-launching windmill catapult a relic of the good old days of warfare, when the infantry hankered after really cold days when the bees would be torpid and much less aggressive.

But, as a couple of masochists have already demonstratedApis mellifera is pretty tame where stinging is concerned.

Apis dorsata, the giant honey bee of South East Asia, is much bigger than our honey bee, and is reputed to pack more of a punch when stinging 7.

These bees build large exposed nests and the colony may have up to 100,000 bees in it.

Apis dorsata nest, a single exposed comb which may be a metre wide.

Which doesn’t mix too well with gunpowder or, more specifically, a firecracker containing gunpowder.

During the Vietnam War the Viet Cong would attach firecrackers to dorsata nests relocated to the jungle trails used by the enemy. As a patrol passed by they would ‘light the blue touch paper’ and set off the firecracker.

And then stand well back.

And, at about the same time (1960’s), the Americans were developing chemical warfare approaches using isopentyl acetate, the alarm pheromone, with the intention of spraying it onto enemy troops and redirecting the bees to attack them instead.

Six-legged soldiers

There’s lots more in Six-Legged Soldiers … get a copy and enjoy reading it over the Christmas vacation. Jeffrey Lockwood is an entomologist and University of Wyoming Professor. The Sunday Times 2009 review of the book criticised it as ‘scarcely scholarly’, being a mix of myth, legend and historical facts.

I cannot imagine a better review and it probably explains why it is so entertaining to read 🙂

Mite bombs

These are something altogether different to bee bombs … and for regular beekeepers, much more relevant.

A mite bomb is a heavily mite infested and collapsing colony that liberally spreads Varroa mites around the neighbourhood. Recent evidence suggests that this occurs primarily during late-season robbing of weak (mite infested) colonies by strong colonies.

This is the primary reason late summer miticide treatment should be coordinated over a wide geographic area. What’s the point of treating your strong colonies if they’re going to load up on mites when robbing weak colonies in the adjacent fields?

Which reminds me, and should remind you, that winter mite treatments will be needed in the next few weeks to ensure your bees get the best possible start to the new season.

We’ve had a protracted cold period here in Fife and my colonies will probably be treated in the next 5-7 days before there’s a chance they start brood rearing again.


 

Locally adapted bees

This is a follow up to the last post on Strong hives = live hives which was written in response to the oft-repeated mantra that ‘local bees are better adapted to the local environment’.

In that previous post a study of the overwintering survival of colonies headed by queens from very different locations was discussed. There was no difference whether the queen (and consequently all the workers she subsequently mothered) had come from Vermont or Florida.

Instead, the primary correlate of overwintering success was the strength of the colony 1 going into the winter.

Migratory beekeeping

Despite the size differences between the US and UK (or Europe), the honey bee population structure is actually more distinct on this side of the Atlantic.

In the USA the huge impact of migratory beekeeping causes considerable mixing of the bees on the continent. Those on the east and west coasts are distinct, but those in the north and south, or across smaller geographic scales, are really rather similar.

It’s not only commercial migratory beekeeping that enforces this, it’s also some of the very large-scale queen rearing operations. These ship queens all across the USA ensuring that there is less genetic diversity than you’d expect from the vast geographic (and climatic) differences.

Bee caravan

Bee caravan …

So, perhaps the study I discussed last week was not particularly surprising after all … ? 2

In contrast to the US, beekeeping activities in the UK and Europe are rather more localised.

In the UK we still import thousands of queens, but we don’t move our hives across the continent – often more than once a season.

We might take a dozen hives to the heather moors 150 miles away, but we never take them 2500 miles to pollinate almonds.

‘Local’ bees in Europe

Probably as a consequence of less large-scale migratory beekeeping, and less ‘centralisation’ of commercial queen rearing, there is genetic evidence for ‘local’ strains of bees in Europe.

In addition, there is evidence that these genetic differences result in changes to the individual proteins that the bee expresses … and that these may result in local ecological adaptations.

However, this still doesn’t get us to ‘local bees are better adapted to the local environment (and this explains why local bees survive better)‘ …

Andalucian apiary

Local Andalucian apiary

But there is even some evidence to support this last statement as well.

So let’s look at each of these points in turn 3.

Genetically diverse bees

Biologists use the terms genotype and phenotype to describe the genetic makeup of an organism and its appearance. Most beekeepers are familiar with the different phenotypes of honey bee – the dark ‘native’ bees, carniolans, Buckfast etc.

The phenotype is defined and determined by the genotype, but we don’t necessarily know which genes determine which physical characteristic. Population geneticists therefore often use different genetic features to discriminate between different groups or populations.

Microsatellites are DNA markers that contain variable numbers of short tandem repeat sequences. In honey bees, microsatellites are abundant and highly variable. They are therefore very useful for differentiating between populations or groups of populations, though how this is done is outside the scope of this post.

In 1995 Arnaud Estoup and colleagues reported the microsatellite analysis of 9 populations of honeybees from Africa (intermissa, scutellatacapensis) and Europe (mellifera, ligustica, carnica, cecropia), previously distinguished phenotypically. In their enticingly titled paper Microsatellite Variation in Honey Bee (Apis Mellifera L.) Populations: Hierarchical Genetic Structure and Test of the Infinite Allele and Stepwise Mutation Models 4 they support the earlier morphometric (phenotypic) definition by Ruttner of three distinct evolutionary branches of honey bee.

In a series of particularly impenetrable tables and phylogenetic trees they also demonstrate the the European lineages are genetically distinct and, importantly, that sub-populations could be readily identified 5.

Ecological adaptation of bees

Microsatellites are essentially non-functional genetic markers that we can use for analysis. They are carried alongside the thousands and thousands of genes that encode the proteins that make the wings, eyes, guts, feet etc. of honey bees. Other proteins also influence the behaviour of bees – how and when they swarm, their cold tolerance, there longevity.

We can now measure genetic variation of individual genes easily through so-called ‘next generation sequencing’ of the whole genome of the honey bee. However, the variation we see is one step removed from the variation at the protein level that directly influences how the bee copes in (or is adapted to) different environments.

But, it turns out, we can measure the variation at the protein level as well using a technique termed proteome profiling.

If distinct genetic populations of bees have adapted to particular environments (through selection, either natural or by beekeepers) we would expect the proteins they express – that both make the bee and determine its behaviour – should be different.

For example, simplistically, if a bee had evolved to live in a very windy environment we might expect the proteins forming the flight muscles would be stronger, enabling the bee to fly on windier days 6.

Collect the data, decipher what it all means …

Alternatively, you could turn the analysis around:

  • Identify the differences in the proteins that are expressed
  • Work out (or look up) what those particular proteins do and …
  • Conclude that those adaptive changes are required by that sub-population of bees in a particular ecological environment.

And, using proteome profiling, this is exactly what Robert Parker and colleagues reported in 2010 7. They compared proteins from adult bees sourced from geographically dispersed locations (Canada, New Zealand, Chile, USA).

They then grouped proteins into particular pathways e.g. energy metabolism, and observed significant differences.

Pathway analysis of honey bee midgut proteins across the populations studied.

As far as we’re concerned here – which is evidencing that locally adapted bees are actually different from each other in a meaningful way – the precise differences Robert Parker and colleagues aren’t too important.

But … if you insist.

Cold-adapted bees e.g. those from Saskatchewan (SK1, SK2), exhibited much higher levels of proteins involved in heat production in the mitochondria. In contrast, bees from warmer climates e.g. Hawaii (HI), showed higher levels of proteins involved in biosynthesis/folding and degradation of proteins.

Importantly, distinct populations of bees from geographically-distant regions exhibit differences that, logically, could be expected to make them better adapted to that environment.

But, there’s a bit still missing …

The key phrase in that last sentence is ‘could be expected’.

What was not shown in these two studies is that the differences observed are responsible for the better performance or survival of those bees in those environments.

Which finally brings me to a study by Ralph Büchler entitled The influence of genetic origin and its interaction with environmental effects on the survival of Apis mellifera L. colonies in Europe 8.

Local bees do survive better

This was an ambitious and large scale study of the survival of ~600 colonies in 21 apiaries in Europe. The colonies included 5 sub-species (carnicaligusticamacedonia and mellifera) and 16 different genotypes of bees.

In each of the 21 apiaries a local genotype was tested in parallel with at least two non-local genotypes. The large team of scientists/beekeepers involved used standardised management protocols which excluded any form of disease management e.g. no control of Varroa or other diseases. Consequently (many) colonies were lost to Varroa and were removed from the study once infestation levels had reached 10% (i.e. 1 in 10 workers carried phoretic mites) or bee numbers dropped below 5000.

The study started in autumn 2009 and ended in March 2012. During this ~2.5 years 84% of the colonies perished. Almost half of these losses were attributable to Varroa … not a particular surprise.

There are a lot of variables in this study – sub-species (5), genotypes (16), apiaries (21) – so the statistics and analysis are a bit of a minefield.

Count the corpses

Essentially the researchers ‘counted the corpses’ (i.e. colonies that died). They then looked at the survivors and tried to determine the characteristics they shared.

Unsurprisingly, survival of colonies in different apiaries was not the same. Graphed below is the percentage of colonies that survived (vertical axis) in each of the 21 apiaries against time (horizontal axis).

Trajectories of colony survival for the different locations.

These differences are presumably due to local forage availability, colony management, climate etc. We know that bees do better in some places than others 9.

When survival of different genotypes was compared they were much of a muchness, with two outliers.

Trajectories of colony survival for the 16 different genotypes

But, very significantly, colonies headed by local queens did significantly better than colonies headed by non-local queens.

Trajectories of colony survival for the origin of the queens

Why do local bees survive better?

The differences between the two lines – local and non-local queens – in the Kaplan-Meier survival curve above may not look particular good … they both drop disconcertingly quickly, indicating lots of dead colonies.

But it is.

The authors unequivocally demonstrate this statistically, but for beekeeping purposes it’s perhaps even more convincing to simply state that:

“colonies with local queens survived on average 83 ± 23 days longer than those with non-local queens”

That’s a key quote from the paper. It also probably explains why colonies headed by local queen survive better.

In a follow-up paper to Büchler et al., 2014, the same authors did a more in-depth analysis of a range of colony parameters that correlated with survival 10 which contains an additional piece of the jigsaw explaining why colonies headed by local queens survived better.

“colonies of local origin had significantly higher numbers of bees than colonies placed outside their area of origin”

And, by significantly higher, I mean ~20% higher.

Which finally completes the story and brings us back to the Strong hives = live hives from last week.

Local queens head up colonies that survive better in the local environment to which they (and their workers) are adapted.

The colonies survive significantly longer because the colonies are significantly stronger.

Caveats and conclusions

There are a number of caveats to the ‘count the corpses’ study conducted by Büchler and colleagues.

For example, the local bees might have actually been adapted to the local beekeeping management practices. In future experiments there might be ways to control for this 11.

The absence of Varroa control meant colonies were always weaker in the second year of the study. For the majority of beekeepers this is not a sustainable way to manage colonies. A fourth year would have been impossible as they would have run out of colonies.

Nevertheless, under the conditions tested, this is confirmation that ‘local bees are better adapted to the local environment (and survive better)‘.

But as a scientist there’s always another ‘Why?’ question.

Why are the colonies stronger? Is it increased longevity of worker bees? Perhaps it is better foraging skills, meaning more brood can be reared? Is it an adaptation of the queen to the chemicals in the local pollen that increases her fecundity?

Question, questions, questions …

I can think of at least two additional compelling reasons why local bees and queens are preferable. I’ll cover these at some point in the future.


 

Strong hives = live hives

Science and beekeeping make for interesting contrasts and can be awkward bedfellows 1.

Science is based upon observation of tested single variables. multiple repeats and statistical analysis. It builds on what has gone before but has accepted processes to challenge well-established theories. Some of the greatest advances are made by young researchers willing to test – and subsequently overturn – established dogma.

Over the last three generations science – both how we do it and what we understand – has changed almost beyond recognition.

In contrast, beekeeping is steeped in history, has multiple variables – climate, forage, ability – and very small sample sizes. It tends to be taught by the most experienced, passing down established – though often not rigorously tested 🙁 – methods 2.

As a consequence our beekeeping has barely changed over the last three decades. Established dogma tends to stay established.

Local bees are better adapted to local conditions

So let’s look in a little more detail at one of these established ‘facts’ … that locally reared bees are better adapted to local conditions.

The suggestion here is that locally reared bees, because they’re ‘better adapted’ (whatever that means) are more likely to flourish when the going is good, and more likely to survive when the going gets tough.

Furthermore, the implication is that they’re more likely to do better in that environment than bees reared elsewhere (and that are therefore adapted to a different environment).

This sounds like common sense.

Locally bred queen ...

Locally bred queen …

As Brexit looms and the never-ending supply of early-season Greek or Slovenian queens disappears perhaps it’s also fortunate, rather than just being common sense.

But, as a scientist, I’ve spent a career questioning things.

Every time I read the “locally adapted bees survive better (or perform better, or whatever better)” 3 two questions pop into my head …

  1. What’s local?
  2. How did they prove – or how would I test – this?

Spoiler alert

There is evidence that local bees show adaptive changes to their local environment. There is also evidence that local bees do better in their local environment.

Formally, I don’t think scientists have demonstrated that the former explains the latter. This might seem trivial, but it does mean that our understanding is still incomplete.

However, I’m not going to discuss any of these things today – but I will in the future.

Instead I’m going to deal with those two questions that pop into my head.

If we tackle those I think we’ll be better placed to address that dogmatic statement that local bees are better adapted to local conditions in due course.

But perhaps we’ll first discover that other things are more important?

What’s local?

I live most of the time in central Fife. It’s a reasonably dry, relatively cool, largely arable part of the UK with a beekeeping season that lasts about 5 months (from first to last inspections).

Are my (fabulous 😉 ) locally bred queens adapted for central Fife, or the east of Scotland, or perhaps north-west maritime Europe, or Europe?

Where have all my young girls gone?

What a beauty

Would these locally adapted bees do better here (in Fife) than bees raised in the foothills of the Cairngorms, or the Midlands, or Devon or East Anglia … or Portugal?

If you measure the environment you’ll find there’s significant overlap in terms of the climate, the temperature, the forage, the day length (or a hundred other determinants) with other regions of the UK.

The temperature or rainfall extremes we experience in central Fife aren’t significantly different to those in the Midlands. The season duration is different (because of latitude), but I had lots of short seasons in the Midlands due to cool springs and early autumns.

Local is an ill-defined and subjective term.

But there are differences of course. Are Ardnamurchan bees better able to cope with the rain (and the fantastic scenery) than Fife bees? Are Fife bees better able to exploit arable crops than those foraging on the heather and Atlantic rainforests that cloak the hills in the far west of Scotland?

I don’t know 🙁

And there’s something else I don’t know

I also don’t know how I would meaningfully test this.

Just thinking about these types of experiments makes me nervous. Think of the year to year variation – in weather, forage etc. – compounded by the hive to hive variation.

Then multiply that by the variation between beekeepers.

This last one is a biggy. Two beekeepers of differing abilities will experience very different levels of success – quantified in terms of honey yield or hives that survive for example – in the same season and environment.

Doing a study large enough to be statistically relevant without having such enormous variation that the results are essentially meaningless is tricky.

What a nightmare.

Which, in a roundabout way, brings me to a paper earlier this year by Maryann Frazier and Christina Grozinger from Penn State University.

Ask the question in a different way

The title of the paper tells you most of what you need to know about the study.

Colony size, rather than geographic origin of stocks, predicts overwintering success in honey bees (Hymenoptera: Apidae) in the northeastern United States. 4

But don’t stop reading … let’s look in a bit more detail at what they did.

They approached the question (that local bees are better adapted) from a slightly different angle.

Essentially the question they asked was “Does the geographic origin of the bees influence the overwintering survival of bees in a temperate region?”

This question is easier to answer.

They defined the parameters of the experiment a bit more clearly. For example:

  • Rather than looking at several regions they just studied bees in one area  – Pennsylvania (the temperate region in the title of the paper).
  • The bees came from four sources; two were from a hot geographic region of the USA and two from a cold region.
  • They scored ‘doing better’ only in terms of overwintering survival.

By simplifying the question they could reduce some of the variables. They could therefore increase the quantification of the parameters (colony weight, strength/size etc.) that might influence the ‘doing better’.

And in doing so, they came up with an answer.

The study

Sixty colonies were established in three apiaries in Pennsylvania. Two of the apiaries (A & B) were within 1 mile of each other, with the third (C) about 15 miles away. Colonies were generally established from packages 5, to which a queen was introduced from one of four different queen breeders.

Two of the queen breeders were from southern USA (Texas or Florida) and two from northern USA (Vermont and West Virginia 6.

The authors used microsatellite analysis to confirm that the queens – after introduction – headed genetically distinct colonies by midsummer 7.

So far, so good …

They then used standard beekeeping methods to manage the colonies – regular inspections, Varroa treatments as appropriate, feeding them up for winter etc.

They scored colonies for a variety of ‘parameters’; net weight, frames of brood, adult bees and stores.

Four queens failed before winter.

And then they overwintered the remaining 56 colonies …

The results

… of which only 39 survived until April 🙁

39/56 sounds a pretty catastrophic loss to me but it’s actually about the same (~30%) as the average winter losses reported each year in the USA.

So, did the ‘cold-adapted’ 8 Vermont queens survive and prosper? Did the ‘Southern Belles’ 9 from Texas all perish in the cold Pennsylvanian winter?

No.

That’s no to both questions.

There was no significant difference in survival of colonies headed by queens from the north or the south.

The geographic ‘origin’ of the bees did not determine colony survival.

They may have been ‘locally adapted’ (to Vermont, or Texas or wherever) and they were certainly genetically distinct, but it made no difference to whether the colony perished or not in Pennsylvania.

So if the source of the queen didn’t influence things, what did?

Weighty matters

This is the key figure from the paper.

Overwintering success is significantly associated with colony weight.

The heavier a colony was in October, the more likely that the colony survived until April.

The left hand panel shows the probability of a colony surviving (vertical axis, solid line) plotted against the net weight of the colony.

Below about 30 kg colony survival dropped significantly.

The right hand panel shows that net weight alone was not the only determinant. This plots colonies ranked by weight (vertical axis) and indicates whether they survived or not. An underweight (i.e. under 30 kg) colony in apiary C was much more likely to survive than a similar weight colony from the other two apiaries.

Allee, Allee 10

The heavier the colony, the greater the chance it survived. Furthermore, it wasn’t simply the amount of stores available.

Heavier colonies were also larger colonies.

This indicates a so-called Allee effect 11 which is a positive correlation between population density and individual fitness.

This has been shown before for honey bees (and other social insects). For bees we know that the larger the winter cluster the better they are able to maintain the correct overwintering temperature. These large clusters show lower per capita honey consumption to maintain the same temperature when compared to small clusters.

However, in addition to not running out of stores (due to more frugal usage) 12, large colonies will also be better able to rear brood in early spring … ‘it takes bees to make bees’.

Taken together these results demonstrate that colony size and weight, rather than geographic adaptation, is probably the most important determinant of overwintering colony survival.

Disease interlude

These studies were conducted in 2013 (and published in 2019 … a feature of some of my science 🙁 ). In the previous year the authors set up a similar study but did not manage Varroa levels.

Under these conditions only 12% of the colonies survived.

There’s a lesson there I think 😉

This disastrous 2012 study used the same queen breeders to source their queens (from Texas, Florida, West Virgina and Vermont). Some of these queens were described and sold as ‘Varroa-resistant’.

There was no difference in survival (or, more accurately, death) rates between colonies headed by queens described as ‘Varroa-resistant’ or not.

Another lesson perhaps?

Is there a geographic component to Varroa-resistance? Are Varroa-resistant Vermont colonies only actually resistant to mites from Vermont?

Or their viruses? 13

OK, we’re getting distracted … let’s return to apiary C.

Forage diversity and abundance is also important

Colonies in apiary C survived better at lower overall net weights than colonies from other apiaries. In addition, average colony weights were higher in apiary C than in the other two apiaries.

Apiary location significantly affected colony weight and survival.

And the abundance and range of nectar sources was significantly different between the three apiaries used in this study, with colonies from apiary C – located in a less forested and more agricultural area – surviving better.

The proportion of land cover/land use types surrounding apiaries.

The authors suggest that the forage diversity and abundance around apiary C increased the size of the colonies (by boosting brood rearing, adult longevity and colony growth) and that it was this larger adult population, rather than colony weight per se, that was important.

Are we getting the message?

This is the second time in a month that I’ve discussed the importance of strong colonies.

A few weeks ago I discussed how strong colonies are more profitable because they generate a surplus of honey or bees, both of which are valuable.

In this post I show that the primary determinant of overwintering success is the strength and weight of the colony. The source of the queen – whether from the balmy south or the frosty north – had no significant influence on colony survival.

This doesn’t mean local bees aren’t better adapted to local conditions. That wasn’t what was being tested.

However, it does suggest that other things that may be as important, or perhaps more important.

The take home message from this study is keep strong colonies in a forage-rich environment.

In a future post I’ll discuss the evidence that local bees are better adapted … and I’ll make the suggestion that some of these adaptations might be explained because the local genotype actually produces stronger colonies 😉


Note

This was originally published with the title Correlates of winter survival on 8/11/2019 but a hamster running amok in the server meant that the email to those registered to receive announcements of new posts was never sent. Rather than let the post disappear into digital oblivion – as the take home message is an important one – I’m re-posting it again.

With apologies to those who read the original …

Spotty brood ≠ failing queen

I thought I’d discuss real beekeeping this week, rather than struggle with the high finance of honey sales or grapple with the monetary or health consequences of leaving supers on the hive.

After all, the autumn equinox has been and gone and most of us won’t see bees for several months 🙁

We need a reminder of what we’re missing.

Beekeeping provides lots of sensory pleasures – the smell of propolis on your fingers, the taste of honey when extracting, the sound of a full hive ‘humming’ as it dries stored nectar … and the sight of a frame packed, wall-to-wall, with sealed brood.

Brood frame with a good laying pattern

This is a sight welcomed by all beekeepers.

Nearly every cell within the laid up part of the frame is capped. All must therefore have been laid within ~12 days of each other (because that’s the length of time a worker cell is capped for).

However, the queen usually lays in concentric rings from the middle of the frame. Therefore, if you gently uncap a cell every inch or so from the centre of the frame outwards, you’ll see the oldest brood is in the centre and the most recently capped is at the periphery.

It’s even more reassuring if the age difference between the oldest and the youngest pupae is significantly less than 12 days. Hint … look at the eye development and colouration.

This shows that the queen was sufficiently fecund to lay up the entire frame in just a few days.

What are these lines of empty cells?

But sometimes, particularly on newly drawn comb, you’ll see lines of cells which the queen has studiously avoided laying up.

That'll do nicely

That’ll do nicely …

It’s pretty obvious that these are the supporting wires for the sheet of foundation. Until the frame has been used for a few brood cycles these cells are often avoided.

I don’t know why.

It doesn’t seem to be that the wire is exposed at the closed end of the cell. I suspect that either the workers don’t ‘prepare’ the cell properly for the queen – because they can detect something odd about the cell – or the queen can tell that there’s something awry.

However, after a few brood cycles it’s business as usual and the entire frame is used.

Good laying pattern ...

Good laying pattern …

All of these laid up frames contain a few apparently empty cells. There are perhaps four reasons why these exist:

  • Workers failed to prepare the cell properly for the queen to lay in
  • The queen simply failed to lay an egg in the cell
  • An egg was laid but it failed to hatch
  • The egg hatched but the larvae perished

Actually, there’s a fifth … the cell may have been missed (for whatever reason) but the queen laid in it later and so it now contains a developing larva, yet to be capped.

What are all these empty cells?

But sometimes a brood frame looks very different.

Worker brood 1 is present across the entire frame but there are a very large number of missed cells.

Patchy brood pattern

Patchy brood & QC’s …

Note: Ignore the queen cells on this frame! It was the only one I could find with a poor brood pattern.

This type of patchy or spotty brood pattern is often taken as a sign of a failing queen.

Perhaps she’s poorly mated and many of the eggs are unfertilised (but they should develop into drone brood)?

Maybe she or the brood are diseased, either reducing her fecundity or the survival and development of the larvae?

Sometimes spotty brood is taken as a sign of inbreeding or poor queen mating.

Whatever the cause, colonies producing frames like that shown above are clearly going to be less strong than those towards the top of the page 2.

So, if the queen is failing, it’s time to requeen the colony …

Right?

Perhaps, perhaps not …

Which brings me to an interesting paper published by Marla Spivak and colleagues published in Insects earlier this year 3.

This was a very simple and straightfoward study. There were three objectives, which were to:

  • Determine if brood pattern was a reliable indicator of queen quality
  • Identify colony-level measures associated with poor brood pattern colonies
  • Examine the change in brood pattern after queens were exchanged into a colony with the opposite brood pattern (e.g. move a ‘failing queen’ into a colony with a good brood pattern)

If you are squeamish look away now.

Inevitably, measuring some of the variables relating to queen quality and mating success involve sacrificing the queen, dissecting her and counting ‘stuff’ … like viable sperm in the spermathecae.

Unpleasant, particularly for the queen(s) in question, but a necessary part of the study.

However, in the long run it might save some queens, so it may have been a worthwhile sacrifice … so, on with the story.

Queen-level variables in ‘good’ and ‘poor’ queens

By queen level variables I mean things about the queen that could be measured – and that differ – between queens with a good laying pattern or a poor laying pattern.

Surprisingly, good and poor queens were essentially indistinguishable in terms of sperm counts, sperm viability, body size or weight.

Poor queens i.e. those generating a spotty brood pattern, weren’t small queens, or poorly mated queens. They were also not more likely to have fewer than 3 million sperm in the spermathecae (a threshold for poorly mated queens in earlier studies).

Furthermore, the queens had no statistical differences in pathogen presence or load (i.e. amount), including viruses (DWV, Lake Sinai Virus, IAPV or BQCV), Nosema or trypanosomes (Crithidia). 

Hmmm … puzzling.

Colony-level variables

So if the queens did not differ, perhaps colonies with spotty brood patterns had other characteristics that distinguished them from colonies with good brood patterns?

Spivak and colleagues measured pathogen presence and amount in both the good-brood and poor-brood colonies.

Again, no statistical differences.

So what happens when queens laying poor-brood patterns are put into a good-brood pattern hive?

And vice versa …

Queen exchange studies

This was the most striking part of the study. The scientists exchanged queens between colonies with poor-brood and good-brood and then monitored the change in quality of the brood pattern 4.

Importantly, they monitored brood quality 21 days after queen exchange. I’ll return to this shortly.

Changes in sealed brood pattern after queen exchange

Queen from good-brood colonies showed a slight decrease in brood pattern quality (but not so much that they’d be considered to now generate poor brood patterns).

However, surprisingly, queens from poor-brood colonies exhibited a greater improvement in brood quality (+11.6% ± 9.9% more sealed cells) than the loss observed in the reverse exchange (-8.0% ± 10.9% fewer sealed cells).

These results indicate that the colony environment has a statistically significant impact on the sealed brood pattern.

Admittedly, a 10-20% increase (improvement) in the sealed brood pattern on the last frame photograph (above) might still not qualify as a ‘good brood pattern’ queen, but it would certainly be an improvement.

Matched and mismatched workers

Since exchanged queens were monitored just 21 days after moving them all the workers in the receiving hive were laid – and so genetically related to – the previous queen.

The authors acknowledge this and comment that it would be interesting to extend the period until surveying the hive to see if ‘matched’ workers reverted to the poor brood pattern (assuming that was what the queen originally laid).

This and a host of other questions remain unanswered and will undoubtedly form the basis of future studies.

The authors conclude that “Brood pattern alone was an insufficient proxy of queen quality. In future studies, it is important to define the specific symptoms of queen failure being studied in order to address issues in queen health.”

Notwithstanding the improvements seen in some brood patterns I suspect they would be insufficient to justify not replacing an underperforming queen … when considering the issue as a practical beekeeper i.e. there may be improvements but they were much less than could be achieved by replacing the queen from a known and reliable source.

But it might be worth thinking twice about this …

Insufficient storage space

In closing it’s worth noting that I’ve seen spotty or incomplete brood patterns when there’s a very strong nectar flow on and the colony is short of super storage space.

Under these conditions the bees start to backfill the brood box, taking up cells that the queen would lay in.

Usually this is resolved just by adding another super or two.

If there remains any doubt (about the queen) and you’ve provided more supers you can determine the quality of the laying pattern by putting a new frame of drawn comb into the brood nest.

The queen should lay this up in a day or two if she’s “firing on all cylinders”.

In which case, definitely keep her 🙂


 

Website malfunction

The Apiarist is updated every Friday.

Regular as clockwork … except for one Wednesday in May when I pushed the ‘Publish’ button too soon 🙄

However, we’ve had technical issues and I think email subscribers have not been receiving announcements of new posts.

Regular as clockwork

As a consequence of the large number of subscribers who receive ‘new post’ announcements, visitor numbers peak on a Friday evening, remain high over the weekend and then tail off through the rest of the week.

Or they did until ~12 days ago when parts of the site were upgraded and email announcements to subscribers appear to have stopped altogether (I’m a subscriber 1 and I belatedly realised I didn’t get the ‘new post’ announcement). Consequently visitor numbers have flatlined … 🙁

Where have all my young girls gone?

What a beauty

Hopefully this post corrects things … this is what has appeared since the glitch:

  • On Friday 18th October I posted Matchstick miscellany – this is a comment on the recommendation to provide ventilation to hives over the winter. I think the advice is wrong and I explain why.
  • On Friday 25th October I posted Income and outgoings – this is a follow-up to a recent post on beekeeping economics. In this most recent post I describe how to significantly increase profits from beekeeping … by reducing your outgoings and increasing your income.

Please have a read if you’ve not seen these … and apologies for the dual posting if you have 2.

David


 

 

Income and outgoings

I discussed beekeeping economics a couple of weeks ago.

I used some potentially questionable survey data on hive numbers, winter losses, honey yields and pricing, together with ‘off the shelf’ costs for frames, sugar and miticides.

Even ignoring the costs of travel and depreciation on equipment the ‘profit’ was not substantial.

Actually, it was just £102 per colony.

Consider the hard work involved, the heavy lifting, the vagaries of the weather and the amount of honey given away to friends and family.

You are not going to get rich fast (or at all) and the Maldives will have to remain a dream.

What a fantastic beekeeping year that was …

Most of us 1 keep bees for pleasure. However, a small profit from our endeavours can’t do any harm, and may actually do some good.

It might pay for a “sorry I was late back from the apiary … again” crate of beer/bunch of flowers 2 or for the new smoker to replace the one you reversed the car over.

Smoker still life

Smoker

So how do you fund the purchase of a crate of beer/bunch of flowers and a new smoker?

How do you increase the profit per colony from that rather paltry £100 to something a little more substantial?

It’s clear that to do this you need to reduce your outgoings and increase your income.

Income and outgoings

I’m going to restrict myself to the same range of outgoing costs and sources of income to those I covered on beekeeping economics.

I’m ignoring most equipment costs, depreciation, petrol, honey gifts to friends etc. All these reduce ‘profit’.

Here is the summary table presented earlier. Remember, this is for a four hive apiary, per annum 3.

Item Expenditure (£) Income (£)
Frames and foundation 40.00
Miticides 38.00
Food 26.00
Honey (jars/labelling) and gross 63.00 550.00
Nucleus colony 15.00 40.00
Sub totals 182.00 590.00
Profit 408.00

Cutting your food costs

Not a whole lot of leeway here I’m afraid.

Granulated sugar is probably the least expensive way of feeding your bees for the winter. Other than shopping around for the best price there’s not much option to reduce your outgoings.

However, before buying sugar it’s always worth asking your local supermarket for any spoilt or damaged packets. Supermarkets are under pressure to reduce waste and can usually be persuaded to support something as environmentally-friendly as local bees.

It costs nothing to ask.

Many beekeeping associations will arrange bulk purchases of either Ambrosia-type invert syrup or fondant. I’ll comment more extensively on this later.

Cutting your medicine costs

There are even fewer opportunities for savings if you want to use VMD-approved miticides.

I’ve discussed miticide costs extensively in the past. The figures are now a bit dated (and they omitted Apivar which was not available off-prescription at the time). However, it remains broadly true that the annual cost per hive is about the same as a jar of honey 4.

If you’re using Api-Bioxal for midwinter trickling remember that you can safely dilute it to a final concentration of 3.2% (w/v), rather than that recommended on the label. Historically the UK has used oxalic acid at 3.2% and there’s no increase in efficacy at the higher strength. Full details are provided on the preparation of oxalic acid elsewhere.

At 3.2% w/v a 35g “10 hive” pack of Api-Bioxal will treat 15 hives.

There … at £11.95 a packet I’ve just slashed your midwinter treatment costs from £1.20 a hive to  80p.

Look after the pennies and the pounds will look after themselves 😉

Frames and foundation

First quality ‘off the shelf’ frames with foundation cost about £3 each. Obviously it makes sense to shop around and/or buy in bulk.

However, much more substantial savings are possible if you do three things:

  • re-use frames after steaming and sterilising
  • use second quality frames bought on supplier ‘sale days’
  • use foundationless frames

If you nail and glue frames during construction they usually survive at least a couple of trips through a steam wax extractor. Yes, there’s some work involved in cleaning them up afterwards, but it’s no more work than building new frames each year.

Drone-worker-drone

Drone-worker-drone …

Second quality frames are sold in packs of 50 for about £37.50 5. Of the hundreds I’ve used I’ve had few (~2% or less) that were unusable due to knots, shakes, splits or other weaknesses.

Foundationless frames take a bit longer to build and you have additional expenditure on bamboo or wire/nylon. However, this outlay is insignificant when compared with the saving made on foundation.

Remember that foundationless frames built with bamboo supports can go through a steam wax extractor and be put back into service. Don’t use wax starter strips. Use lollipop sticks or tongue depressors fixed with waterproof wood glue.

Take your pick ...

Take your pick …

Purchased premium foundation is lovely stuff but freshly drawn comb on a foundationless frame is even better. Contamination-free, robust once fully drawn and much easier to clean from the frame when it eventually goes through the steamer.

Taken together – re-use, second quality and foundationless – I calculate that frames cost me ~25p each. This equates to a saving of £36.75 over a year 6. Remember also that additional outlay on brood frames is needed to produce nucleus colonies (see below) where the savings would be £13.75 per nuc produced.

That’s more like it 🙂

A co-operative association intermission

Beekeeping associations often have co-operative purchasing schemes. Bulk purchasing reduces both individual item costs and (often substantial) P&P costs. These schemes are often organised to pass on the majority of the discount and retain a small amount of the savings for association activities.

The larger the association the greater the savings that can be made, and there’s no reason why neighbouring associations or regional groupings cannot act together.

Yes, of course, it takes some organisation. If your association doesn’t have such a scheme either find one that does or set up your own.

My beekeeping alma mater (Warwick and Leamington Beekeepers) offered excellent discounts on jars, honey buckets, foundation, Ambrosia, fondant and gloves … and probably a load of other things I didn’t take advantage of when I was a member 7.

Products of the hive

That’s enough about outlay, what about income?

Honey bees make honey and bees.

Both are very valuable.

You can maximise income in two ways.

You can make more of either (or both) or you can sell them at a higher price.

You might even be able to achieve both.

I’ll deal with these in reverse order …

Maximising the prices of honey and bees

I’ve discussed honey pricing recently. If you’re producing a unique, high quality, well packaged product (and if you’re not, you should be) you need to price it accordingly.

More local honey

That’s not the £4 a pound charged for the imported, blended, filtered, pasteurised, uniform, dull, available-by-the-tonne-anywhere rubbish stuff sold by the supermarkets.

Look in the delicatessens and local artisan outlets … you might be surprised.

£10 a pound is not unreasonable.

£10 a pound is readily achievable.

But let’s not be greedy, let’s assume a very conservative £7.50 a pound.

Local honey

At £7.50/lb the average UK yield of 25lb of honey per hive equates to £687 (for the four hives) after paying out £63 for jars and labels 8

Two factors contribute to the price you can realise for bees (which, for this exercise, means nucleus colonies):

  1. Timing – to maximise the price you need to sell when demand is the highest and supply is limited. This means early in the season. You therefore must overwinter nucs and ensure they are strong and healthy in mid-late April. Four to six weeks later there’s a glut of bees available as colonies start swarm preparation … prices drop precipitously. Nucs are easy to overwinter with a little TLC.
  2. Quality – with a small number of colonies it is not easy to improve your stocks. However, by judicious replacement of poorly-performing queens/colonies you should be able to produce perfectly acceptable bees for sale. Don’t try selling bad bees – chalkbrood-riddled, poorly behaved, patchy brood or diseased (high Varroa, overt DWV etc.).

If you are selling one or more nucs you should expect to allow them to be inspected before the sale. Just like honey tasting, nothing is more convincing than trying the product.

Maximising the amount of honey and bees

All other things being equal 9 stronger colonies will produce more honey and generate more ‘spare’ nucs.

Compare a productive commercial colony and an unproductive amateur colony at the height of the season. What’s the difference?

Mid-May ... 45,000 bees, 17 frames of brood, one queen ... now marked

Mid-May … 45,000 bees, 17 frames of brood, one queen … now marked and clipped

The productive colony is on a double brood box underneath three or four full or rapidly filling supers. There are 16+ frames of brood and the beekeeper has already split off a nuc for swarm control.

In contrast, the unproductive colony has about seven frames of brood in a single brood box topped by an underwhelmingly light super. There’s little chance of producing a spare nuc this season … or much honey.

But at least they might not swarm 🙂 10

Generating these strong colonies requires good genetics and good beekeeping.

With further good management the productive colony could produce another couple of supers of late-season honey and at least one more nuc for overwintering.

Here's one I prepared earlier

Here’s one I prepared earlier

How does that help the bank balance?

Let’s assume an ambitious-but-not-entirely-unrealistic one nuc per colony and 75lb of honey per annum in total (being sold at £175 per nuc and £7.50 a pound for honey). Honey ‘profit’ for the four colonies in our hypothetical apiary works out at £2061 11 with a further £700 for the sale of four nucs at £175 each 12.

That works out at a very much more impressive £690 per colony.

Minimising losses

But wait, surely we have to use some of those valuable nucs to make up for the 25% overwintering colony losses that the average UK beekeeper experiences?

No we don’t 🙂

If you have the beekeeping skills to manage strong colonies you almost certainly also have below average overwintering losses.

And that’s because strong colonies are, almost by definition, healthy colonies which have low mite and virus levels. And, as we’ve seen time and time again, low virus levels means reduced winter losses.

This minimises the need for nucs to maintain overall colony numbers and so maximises the nucs for sale 🙂

For the sake of finishing this already overly long post, let’s assume overwintering colony losses are 12.5% (because it makes the maths easier … 10% or lower is readily achievable) rather than the 25% national average.

That being the case, for our four hive hypothetical apiary, we’ll need one replacement nuc every two years. Therefore, over a four year period we might generate 16 nucs and use just 2 of them to replace lost colonies.

Kerching!

Here are the figures for our hypothetical four colony apiary. These assume good bees, good beekeeping, low winter losses, good forage, good weather and a following wind.

I’ve assumed savings are being made where possible on frames and foundation, but also increased the number of frames (and miticides) needed to reflect colony size and strength.

Item Expenditure (£) Income (£)
Frames and foundation 7.50 13
Miticides 76.00 14
Food 52.00 15
Honey (jars/labelling) and gross 189.00 16 2250.00 17
Nucleus colony 5.00 18 612.50 19
Sub totals 329.50 2862.50
Profit 2533.00

Per colony the overall profit is £633/annum (cf £102/colony/annum for an ‘average’ hive and beekeeper).

These figures are not unrealistic (though they’re not necessarily typical either).

They won’t be achieved every year. They are dependent upon good forage, good weather and having the beekeeping skills needed to maintain strong healthy colonies.

They might be exceeded in some years. With good forage and a good season 100+ pounds of honey per colony can be achieved.

You have no control over the weather 20, but you can influence the other two factors. You can place your bees on better forage and you can continuously try and improve your skills as a beekeeper.

And learning how to maintain (and keep!) really strong healthy productive colonies is demonstrably a very valuable skill to acquire.

E & OE

Just like in the previous article, I’ve made all sorts of assumptions and cut all sorts of corners.

Managing big strong double-brood colonies producing a nuc each every year and topped by at least three supers inevitably means investing in lots more brood boxes, supers and nuc boxes 21.

It also means a lot more work.

Extracting and jarring hundreds of pounds of honey takes time. It also benefits from some automation … an extractor, a creamer, settling tanks, a honey processing room, a warm room for supers etc.

But that lot is not needed for our well-managed four hive hypothetical apiary.

The other things I’ve deliberately omitted are alternative ways of managing colonies for profit. For example, as suggested by Calum in a previous comment, propolis is a very valuable product of the hive. You can split a strong colony very hard to generate 6-10 nucs (but no honey). You can rear queens (very easily) and you can sell wax.

You could even produce Royal Jelly …

And it’s that endless variety and options that make beekeeping so fascinating.