Dealing with DLW’s

This is a continuation of the post from last week (Drone Laying Workers; DLW’s) on possible ways to fix things if you only have small numbers of colonies. If you have loads of colonies and/or have no interest in maintaining colony numbers you can simply shake the bees out or unite with a strong colony … there’s  no need to read any further. However, if you have only two or three colonies and want to keep them then this might work for you.

Disclaimer … this works for me but there are no guarantees 😉

Drone laying workers ...

Multiple eggs …

Although DLW’s can clearly return to a colony after shaking them out (see image right and the explanation of what it shows posted last week), the numbers are significantly reduced … or at least look as though they are. To be pedantic you actually can’t be sure the number of DLW’s is reduced without formally testing it … perhaps they’re all still present, just laying fewer eggs? I can’t think of an easy way to discriminate between fewer and the same number doing less. Can you?

However, I think it’s reasonable to assume that the numbers are reduced based upon two observations:

  • the number of ‘mislaid’ eggs per day appears to be lower in what is still a broodless and queenless hive (i.e. the same conditions that prevailed before shaking the bees out)
  • a colony that has previously refused to draw queen cells on an introduced frame of eggs and young larvae is – in my experience – much more likely to do so after shaking them out

The second observation is, to me, the clincher. Colonies with well-established DLW’s often completely ignore the first frame or two of open brood added to them. They rear the larvae as normal, but don’t start generating queen cells because they still consider themselves queenright. Remember, as discussed last week, it is the open brood pheromone that suppresses ovary development by workers and you may need to repeatedly add a new frame of open brood every few days before you finally overcome this. With only a couple of colonies, the DLW’s might be saved but the other colonies will definitely be weakened.

However, if you combine shaking the bees out with the addition of a frame of eggs and young larvae there’s a reasonable to good chance they’ll recognise their queenlessness and start drawing out emergency queen cells (QC’s). Once that’s been achieved you’re in a much better position to rescue the colony.

Prevention is better than cure

Drone laying queen ...

Drone laying queen …

Far better you identify a colony is queenless and resolve that before they are irretrievably broodless. This requires regular inspections and careful observation. Once the colony appears queenless and devoid of worker brood you need to look for the characteristic signs of a random pattern of drone brood in worker cells and multiple poorly placed eggs. Remember that newly mated queens sometimes lay multiple eggs per cell, but – at least in empty drawn comb – these are more likely to be clustered in the centre of the frame within an area of ‘polished cells’ prepared by the workers. In contrast, DLW’s eggs are usually dotted all around the place (see the image at the bottom of this article). The only other queen problem DLW’s can be confused with is a drone laying queen … in these colonies there is usually a clustered pattern of drone brood (see image right and compare it with the one further down the page), sometime mixed with worker brood if she’s only just starting to fail, in the centre of the frame.

Don’t leave things too late

If you’re confident in your diagnosis of drone laying workers then don’t delay. The longer you leave things the worse the situation will get … more workers will start laying eggs, the colony will weaken, the younger bees in the colony will age etc. All of these things makes rescuing the situation less likely. If you’re not confident in your diagnosis then ask someone else.

Once I’m confident a colony has DLW’s I do the following:

  • move the original colony as far away as practical, but typically 50-100 yards 
  • replace the original hive with a new floor facing the same direction, a brood box containing drawn comb, some stores, some foundation if needed and a single marked frame of eggs and young larvae placed centrally. Add the crownboard and roof.
  • shake out the original colony completely, removing every frame and vigorously shaking all the bees off (you can use a bee brush, but it’s actually far gentler to learn to give each frame one or two hard ‘snaps’ and shake the bees off … the brush always aggravates the bees)
  • carefully inspect the ‘new’ colony in the original location 2-3 days later
Marked frame (X) with larvae and eggs ...

Marked frame (X) with larvae and eggs …

Queen cells … we’re saved!

Don’t wait too long until you inspect the colony. Three days is more than enough. You’re looking for two things:

  • one or more new queen cells on the marked frame
  • the absence – or more probably significant reduction – of ‘mislaid’ eggs in worker cells on the unmarked frames of drawn brood in the colony
Queen cell

Queen cell …

Of these two, the presence of queen cells is critical. If there are no QC’s then the colony still considers itself queenright. I’m afraid my interest and enthusiasm for saving the colony rapidly dwindles at this point and I usually shake the colony out again in front of other strong hives in the apiary (having removed the original hive completely so no bees can return to it ).

If there are QC’s the colony considers itself queenless (even if there is some evidence of eggs laid by workers on other frames) and there’s a very good chance you’ll be able to save it. At this stage your options include:

  • allow the colony to raise their own queen, remembering that this takes time (perhaps 3-4 weeks) and that queen mating is both weather and drone dependent. If it’s late in the season it’s, at best, likely to be a risky strategy.
  • requeening the colony using a mated queen from elsewhere, in which case add the queen cage adjacent to the introduced frame of brood.
  • uniting with a queenright nuc, even one that isn’t overly strong. Since the receiving colony now knows it’s queenless they’re far more likely to accept the new queen. Nevertheless, you still need to use newspaper or one of the other methods that ensures the gentle merging of the two colonies.
Successful introduction ...

Successful introduction …

Tidying up

Drone laying workers ...

Drone laying workers …

I usually discard the frames containing drones in worker brood, particularly those with a large number of occupied cells (see right). Alternatively, you can distribute them to other colonies in the same apiary. It’s best not to switch them between apiaries to prevent the spread of diseases. However, because of the high level of drifting and the movement of drones between colonies, hives in the same apiary can broadly considered as a single super-colony. If there are frames of stores in the original colony they can be saved for use later in the season, remembering to protect them from robbing bees and wasps.

Advantages and disadvantages

I assume this approach works because shaking the colony out at least partially reduces the number of DLW’s which, once they’ve returned to the new hive containing open brood and eggs, realise their queenlessness and start to do something about it, whilst at the same time the brood pheromone suppresses the further development of ovaries and egg laying in the workers. I’ve had more success, and much faster, with this approach than with the repeated addition of frames of open brood. I’ve also had colonies that refused to make QC’s on added frames do so after shaking them out …

The advantages are three-fold:

  • it only requires a single frame of eggs and young larvae. Your other colonies are not significantly weakened while trying to ‘save’ the drone laying colony.
  • it’s pretty quick. From diagnosis until you’re in a position to know you’re ready to proceed only takes three days.
  • if successful (i.e. new QC’s) you can be reasonably confident the colony can be saved. And, as far as I’m concerned, if unsuccessful (i.e. no QC’s) I need spend no further time or resources on the colony.

Disadvantages:

  • it needs more than one visit
  • it involves more physical work
  • it requires more equipment

If you try this approach I’d be interested to hear how you get on with it.


† it’s worth noting here that the majority of the shaken out colony will return to the nearest colony to their original location. Do not leave an Apidea containing a recently mated queen, or a  weak nucleus colony nearby or they will be inundated with bees … with potentially disastrous consequences.

I assume that the further you move the colony the less chance the DLW’s will return to the original hive, but have no evidence for this. Would success be more likely if you moved them a mile away? So many questions, so little time

 

8 thoughts on “Dealing with DLW’s

  1. Edward

    Very informative thanks for going to trouble posting I read all your posts and enjoy reading them although I don’t comment on them keep up the good work

    Reply
    1. David Post author

      Thanks Edward
      Only a fraction of those who read post a comment … if everyone did I’d never do any beekeeping 😉
      I’m pleased you enjoy reading them.
      Cheers
      David

      Reply
  2. Tim Foden

    Hi David

    I’m a bit surprised to see you using the expression drone laying workers. I always thought that laying workers would suffice as laying workers of course can’t lay fertilized eggs. DLQs is entirely acceptable for obvious reasons.

    I have had several instances of laying workers this year and thought I could resolve the problem and save some bees by shaking the bees out at a distance and having some of them returning to a queenright nuc box. I won’t try it again as they killed the queens!

    Do you think that the workers that are actually laying look any different to those that aren’t?

    Best wishes

    Tim

    Reply
    1. David Post author

      Hi Tim

      You’re right about the name … it’s habit, and possibly a bad one. I’ve got worse. As an acronym DLW’s makes a nice contrast to DLQ’s. However, don’t forget Apis mellifera capensis, the Cape honey bee. This subspecies can – due to the presence of a recessive gene – undergo a sort of parthenogenesis (called thelytoky) and the workers lay diploid eggs leading to female progeny. I don’t know whether A. m. capensis can also produce drone laying workers.

      My understanding is the (D)LW’s are indistinguishable externally. The people I know who have found them have had to search for one in the process of laying an egg. Time consuming. Interestingly, they are present in low numbers in a queenright colony as well. Years ago Ratnieks dissected workers from a queenright colony to check for eggs and found them present in about 1:10000 workers. He also measured the egg laying rate above the QE and found 1 per 16000 cells, of which only a couple of percent hatched. I usually find one or two drone pupae when I extract … I’ve got a photo of one somewhere. I’m really pleased people have taken the time to do these experiments … it means I don’t have to 😉

      Reply
  3. Meriel Bottle

    I read all your posts with great interest and dont usually leave replies either. This one was particularly interesting to me as I have had 3 colonies with laying workers this year. I only wish you had posted this a couple of months ago! I will certainly try this method if (when!) it happens again.

    Do you think that option 1 of allowing the shaken out colony to raise its own queen from an emergency queen cell is a good idea?. It seems to me that by the time you get to this state most of the workers are likely to be quite old and therefore not the best at raising an well nourished queen who will go on to be a good layer. Much better to use option 2 or 3 and use a queen raised elsewhere. ?

    And PS you have a typo “even if there is some evidence of eggs laid by drones on other frames”

    Reply
    1. David Post author

      Thanks for spotting the typo Meriel … now corrected.

      Of the three methods suggested I’d usually choose queen introduction or some form of uniting. I think I had four in total this year – one got a new queen, two were united with nucs and one refused to ‘play ball’ and was eventually shaken out. However, I was mindful I was writing for beekeepers with small numbers of colonies and they might not have the luxury of a spare queen or nuc for uniting. Aside from the age of the workers that would be responsible for raising the new queen, there would also be an even longer brood break meaning option 1 is really only practical early enough in the season for the colony to build up sufficiently for winter.

      Reply
  4. Calum

    Hi, just been through the mill of this, it cost me 3 queens – a colony was just eating them.
    Talked to a local guy that has 200 colonies, he advised me that shaking the bees off is a poor solution, as the bees that are becoming DLWs can easily fly back, get through an excluder in front of the entrance and tear down queen cells, or kill queens.

    He recommends (and it worked fine for me). Place the DLW hive 50m away, and set up a new hive on the spot where the DLWH was. The non DLWs will fly home, the DLWs and developing DLWs will stay in the old hive. The old hive should be killed of with sulphur strip after 2 weeks.

    Seems logical, and much less work, for a certain outcome.
    BR
    Calum

    Reply
    1. David Post author

      I can see that being a logical solution Calum. It needs the beekeeper to have space to re-locate the hive for a fortnight or so which might not be convenient. I’d also favour seeing the evidence that they’re likely to accept a new queen – by the development of queen cells – before adding one. In previous years I’ve struggled to re-queen large aggressive colonies and have lost several queens during the attempts, so you have my sympathies.
      Cheers
      David

      Reply

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