Tag Archives: robbing

No, not really …

Was it good for you? … No, not really.

I recently posted the weather forecast for the week beginning the 15th of August. I was pleased that the forecast was for near-perfect queen mating conditions – sunny, warm and calm – as I had three colonies which should have contained virgin queens that were due to emerge a few days before.

The forecast was very accurate. Conditions were wonderful. I wasn’t around as I had disappeared to Torridon and Skye for a few days. On checking the colonies at the end of the week after I returned, all three contained queens at least two of which were laying.

Beinn Eighe

Beinn Eighe …

All good then …

Well, not entirely, because mid-afternoon on the previous Wednesday I’d been sent an email from my friend at the apiary that read … “Incredible roaring noise attracted me outside the workshop – a swarm moving west through the garden and into the trees.  All caught on camera”. I didn’t receive the email as I was in the howling wilderness. Not that I could have done much about it.

A very quick inspection of the colony in question on my return confirmed that they’d swarmed. D’oh! I’d obviously missed at least one additional queen cell (mistake #1) on the last inspection and a large cast (the queen must have been a virgin as the original queen had been removed from the colony) had disappeared over the fence … mistake #2. There was a queen present but bee numbers were significantly down. I closed the colony up and disappeared on business for a further three weeks … mistake #3.

The weather had been great the entire week I was away in Torridon. I suspect the colony swarmed on the Monday or Tuesday, that it hung around in a nearby tree until the Wednesday while the scout bees found somewhere more desirable to relocate to, and that my friend had seen it leaving the neighbourhood that afternoon.

Lessons learned

  1. Don’t let the colony decide how many queens should emerge. Instead leave only one known charged (occupied) queen cell to emerge. I’d left an open queen cell on a marked frame, but had not returned a few days later to check that a) it was safely sealed and b) that they hadn’t raised anymore. They had 🙁  Consequently they swarmed when the first queen emerged, leaving one or more additional queens to emerge, fight it out and then head the now much-depleted colony (see 3, below).
  2. Leave a bait hive in or near the apiary, even if the main period of swarming has passed. I’ve been very successful with bait hives over the years, successfully attracting my own and others’ swarms. In this instance the main swarming period was well-passed and I’d packed away my bait hives until next Spring. Wrong. Had I left one near the apiary I may well have managed to attract the swarm and so a) not lost the bees, and b) not potentially inflicted the  bees on someone else. I view bait hives (and queen clipping) as part of being a good neighbour.
  3. Don’t leave a weakened colony late in season. On returning from my three week absence for work I discovered the colony had been robbed out and destroyed. Clearly it had been unable to defend itself from robber bees or wasps and had perished. I should have instead made an executive decision on discovering the colony had swarmed and probably sacrificed the virgin queen and united the weakened colony with a strong colony nearby. In retrospect this was an obvious thing to do … the colony was weak, wasps were beginning to be a problem, there was little or no nectar coming in and the weather was uncertain. As it turned out the weather was good enough for queen mating while I was away. However, the combination of a dearth of nectar, a weakened colony and strong neighbouring colonies meant that robbing was inevitable and – for the colony in question – catastrophic.
Skye ...

Skye …

Had I thought carefully about things in mid-August I may have been able to prevent the inevitable carnage when the colony was robbed out. In my defence I’ve only been around for a day or two over the last month, with extended periods out of the country on business. Nevertheless, this was clearly a case of a lesson (or three) learned the hard way …


† If you’ve not read Tom Seeley’s outstanding Honeybee democracy about how a swarm decides where to relocate to you should.

What was that?

Zoom. Having moved back to Scotland in mid-2015 this is my first full season keeping bees here. The season has been very short. Some colonies weren’t inspected until the end of April and now, about 14 weeks later, it’s turned distinctly autumnal over the last week or so in Fife. Nectar flows have pretty much dried up, nights are much cooler and thoughts turn to preparing colonies for the winter. However, good winter preparation with strong, disease-free colonies and low Varroa levels means that, should Spring 2017 be early, the bees will be ready to take advantage of it.

The immediate priorities are to:

  • protect colonies from robbing
  • ensure colonies have enough stores
  • remove any honey for extraction before the bees use it

Robbing b’stards

Entrance reducer ...

Entrance reducer …

The very best way to protect colonies from robbing – either by other bees or wasps – is to keep them as strong as possible. Wasps can be very troublesome in the autumn. Smaller colonies and nucs are particularly susceptible to attack and can be devastated in just a day or so if not properly looked after. A block of foam or wood can easily be pushed into place on a full hive, reducing the space the bees need to defend. The underfloor entrance of kewl floors (right) have the added advantage of a narrow L-shaped tunnel that can be defended on the landing board and/or immediately below the frames.

It’s not unusual to have 2-4 frame nucs in mid-August, either being prepared for overwintering or with ‘backup’ queens while re-queening other colonies. If the colonies aren’t really strong enough to defend themselves they need to be given all the help they can. Reducing the entrance space to a single bee width helps a lot, particularly when the entrance is as cavernous as the design on the Thorne’s Everynucs that I use.

Reduced entrance ...

Reduced entrance …

Stores

There’s still sufficient time for strong nucs to be built up to occupy a full hive, but they need to be given sufficient space for the queen to lay and will probably require feeding unless there’s a good late-season nectar flow. This nuc (below) started the first week of July on just a frame of emerging brood, a frame of stores and a new queen and is just about ready for a full hive. Although not obvious from the picture, the feeder on the left contains a large block of fondant which the bees are busy with. This was added as soon as the flow stopped and before the nuc got dangerously light. The bees might have survived but the queen would have slowed or stopped laying eggs and development of the colony would have been retarded. This nuc is fast running out of space and will be moved into a full hive in the next day or two.

5 frame nuc ...

5 frame nuc …

The  integral feeder on these Everynucs has space for about a kilo of fondant. Here’s another nuc started a fortnight ago with a ‘backup’ queen that was also light on stores. The parent colony were showing signs of replacing the queen so I removed her and a couple of frames of emerging brood and left them in the corner of the apiary with the entrance stuffed with grass (to deter the flying bees from returning to the original colony). After a couple of days I removed the dried grass and they’re now ticking along nicely. As they’re a smaller colony and contain predominantly young bees they lack a strong force of foragers and so need regular feeding. If the original colony successfully rears a new queen I’ll have a spare for overwintering. If not I’ll unite them back together at the end of the month.

Nuc with fondant ...

Nuc with fondant …

This is the same nuc as shown in the top image with the reduced width entrance. One of the advantages of feeding fondant is there’s no chance of slopping it about and leaving spills to attract wasps to the apiary.

The image above also shows a ‘crossbar’ I add to the Everynuc feeders; this prevents the frames sliding backwards when the nucs are in transit between apiaries. The integral feeder is useful, but it means there’s no ‘stop’ against which the end of the frame topbar can rest. There is a stop fitted across the bottom of the face of the feeder (shown in a previous post) but my experience is that the inevitable jolting of a car journey means the frames lift above this and then can slide about too much with the risk of crushing bees.

Supers off

I’m resigned to it being a poor summer for honey this season – a combination of a late spring and consequent slow colony development, variable weather during the summer and an extended queenless period for many colonies due (again) to lousy weather for queen mating. Clearers are now on the majority of colonies with filled supers. I’ll retrieve all the filled frames for extraction and make up new supers with the leftovers (incompletely filled or too high water content). The latter will go back onto strong colonies, either in the hope of a late season top-up from the himalayan balsam or for winter stores.

Clearers on ...

Clearers on …


The opening video clip was from the second series of Fawlty Towers first shown in 1979. Immediately before it Basil and Sybil are discussing their early married life …

Basil Fawlty … “Seriously, Sybil, do you remember, when we were first manacled together, we used to laugh quite a lot?”

Sybil Fawlty … “Yes, but not at the same time, Basil.”

Just retrieving the clip from YouTube means I’ll now be spending half the evening chuckling over other bits of this classic series.

Basil Fawlty … “Well… may I ask what you were expecting to see out of a Torquay hotel bedroom window? Sydney Opera House, perhaps? The Hanging Gardens of Babylon? Herds of wildebeeste sweeping majestically…”

Keep your distance

A recent paper by Nolan and Delaplane (Apidologie 10.1007/s13592-016-0443-9) provides further evidence that drifting/robbing between colonies is an important contributor to Varroa transmission. In the study they established multiple pairs of essentially Varroa-free colonies 0, 10 or 100 metres apart and then spiked one of the pair with a known number of Varroa. They then monitored mite build-up in the paired colonies over several months. By comparison of the relative mite increases in colonies separated by different distances they showed that the more closely spaced, the more likely they were to acquire more Varroa, presumably through robbing or drifting.

This isn’t rocket science. However, it’s a nicely-conducted study and emphasises the importance of colony spacing on the transmission of phoretic mites between infested and uninfested colonies – through the normal colony activities such as robbing and drifting – as a primary cause of deformed wing virus (DWV) disease spread in the honey bee population. The paper only studies mite levels, but the association with DWV transmission is well established and unequivocal.

Related studies on the influence of colony/apiary separation

The introduction to the paper provides a good overview of the prior literature on the impact of drifting on disease and Varroa transmission, some of which has already been discussed here. However, some of these studies have not previously been mentioned and deserve an airing, for example:

  • Sakofski et al., (1990) showed that there was no difference in mite migration between colonies in closely-spaced rows from those located up to 10m apart.
  • Frey and Rosenkranz (2014) showed that high-density colonies (>300 within flight range [2.5 km] of the sentinel colonies) experienced approaching 4-fold greater inbound mite migration than when located in areas containing a low-density of treated colonies. Over a 3.5 month period the difference was 462 +/- 74 vs. 126 +/- 16 mites. This would have a very significant impact if allowed to subsequently replicate in the recipient colonies.
  • Frey et al., (2011) previously investigated mite transfer between colonies located 1m to 1500m apart. Strikingly, in this study (which was conducted during a dearth of nectar) mite transmission was effectively distance-independent, with the recipient colonies acquiring 85 – 444 mites over a 2 month period.
Frey and Rosenkranz (2014) Mite invasion ...

Frey and Rosenkranz (2014) Mite invasion …

What can we conclude from these studies?

  1. Closely-spaced colonies – for example, the sort of distances used to separate colonies in an apiary – should really be viewed as a single location as far as mite infestation is concerned. A single heavily-infested colony in an apiary will quickly act as a source of mites to all other colonies.
  2. High densities of beekeepers – assuming the usual range in both the timing and vigour with which Varroa control is practised – is probably detrimental to maintaining low mite levels in your own bees.
  3. Significant mite transmission occurs over distances of at least 1.5 km … not just between hives in a single apiary. How many colonies are there within 1.5 km of your own apiary? Even if you are careful about controlling mite levels, what about all the beekeepers around you?
  4. Colonies wth uncontrolled levels of mite infestation, abandoned colonies (or swarms that occupy abandoned hives) and feral colonies located at least 1.5 km away are potential sources from which your carefully-maintained hives get re-infested …

Recent experience with high and low density beekeeping

One mile radius ...

One mile radius …

I’ve moved in the last year from the Midlands to Fife. Beebase and my involvement with local beekeepers suggest that these represent areas of high and low colony-density respectively. For comparison, Beebase indicates that there were over 230 apiaries within 10 km of my home apiary in the Midlands and that there are currently 20 within a similar range in Fife. In the Midlands I was aware of at least 25 colonies (in several different apiaries) within a mile of one of my apiaries. Furthermore, apiaries might contain lots of hives … one of those previously within 10 km of my home apiary was our association apiary which held up to 30 colonies from ~15 beekeepers. In contrast, the closest beekeeper to my current home apiary is almost 3km away … though I acknowledge there may well be hives “under the radar” belonging to beekeepers that are not members of the local association or have not bothered to registered on Beebase (why not?). It’s far too early to be definitive but mite levels in my colonies have been reassuringly low this season. This includes uncapping hundreds of drone pupae – the preferred site for Varroa to replicate – without detecting a single mite. I’d like to think this was due to timely and effective Varroa control, but it is undoubtedly helped because my neighbours are further away … and perhaps better at controlling the mite levels in their own colonies.

This study provides further compelling evidence of the importance of either keeping colonies isolated (which may not be possible) and ensuring that all colonies in the same and adjacent apiaries are coordinately treated during efforts to control mite numbers.

Gaffer tape apiary

Gaffer tape apiary …