Losing Queens On Mating Flights

Virgin Queens Are Not Making It Back

I’m deep into writing a book, with the deadline approaching faster than my output of words, but it seems wrong to neglect my blog for too much longer. This one is not very scientific, just some observations and musings about some changes that I have seen in the last two seasons. It’s only now, having gone through my notes (on a spreadsheet, naturally) that I realise that the majority of my losses this season were ‘summer losses’ rather than the expected ‘winter losses’.

The main issue seems to be that virgin queens are not returning from mating flights, for whatever reason. Either that, or they do return but don’t last long. Here are some typical examples:

• I removed the queen and some brood as part of swarm control, leaving one unsealed queen cell. Result: no queen, sometimes laying workers
• As above, but there were ripe queen cells in the hive, so I released several virgins. Result: no queen, sometimes laying workers
• Swarms that I caught by shaking into a nuc from a tree branch, including some giant ones, seem to have been cast swarms. Result: no queen, dwindled away
• Strangely, swarms that turned up in empty hives seem to have been prime swarms that have done well, although often the queen is superseded after a few weeks. Why did these supersedure queens get mated when the virgins in the other swarms did not. Surely, the ‘cast swarms’ can’t have been queenless, can they?
• On ‘double-decker’ nucs, I took away 5 frames and the queen to sell, then left the remainder to make a replacement. Result: no queen, laying workers
• Colonies that swarmed, and I left one good queen cell. Result: no queen
  

All In A Row

When I spoke to a bee farmer (Paul Horton) about this, he told me that he’d suffered from the issue of queens failing to return from mating flights rather frequently. He put it down to the layout of his hives; in a row along the edge of a field, with few landmarks. He later experimented using coloured correx landing boards with various shapes/symbols printed on them (see pictures). It was a big success, with something like 27 mated queens from 30 (90%). On reflection, although I try to use mating nucs with different colours and markings, most of my hives look very similar.

Paul told me that he had looked into the way that bees use landmarks to navigate back home. One problem with hives in rows is that bees don’t seem to be able to count to more than three. For example, using the end hive as a ‘landmark’ they don’t seem to have an issue differentiating between the first three hives in the row. But once you get to the fourth, fifth, six and so on, they seem to lose their bearings. One way around this is to break a row of hives into little clusters of three hives, then a gap, then another three hives, and so on.

I’m accustomed to mating failures when I have grafted too early and then the weather has gone horrible. That happened last year. I am now convinced that, for me, I need to get all of my queen rearing using keiler baby nucs done in June and July. May is unreliable and August risks wasps. I think I’m getting the hang of ensuring that my grafted virgin queens turn into juicy fat mammas.

Why Now?

One thought does niggle at me, though; why have I suddenly started having these ‘failed mating flight’ difficulties in the last year or two, and not before? I am not convinced that the thing I’m seeing is poorly mated queens, which could possibly be explained by the impact of mite treatments and pesticides in the environment causing problems with sperm viability in drones. Neonics, which mess with the navigational abilities of bees, have not been around in the last few years. When they were being used, I didn’t have as noticeable an issue as I do now, so I don’t think they are the cause.

The only thing I can think of is that maybe I’m interfering with colonies that have virgin queens a bit too soon. Perhaps next season I will leave them alone for longer. The concern with that, though, is that after being left alone for six weeks, if the queen hasn’t got mated, there’s not really anything much left to try to rescue – just a load of old hopelessly queenless bees.

There is a paper, published in 2018, called ‘Drifting of honey bee queens returning from flights’ which said that “The smallest percent of lost queens was found in colonies in which the hives were irregularly placed facing different directions and near landmarks in the vicinity.” They did not find any difference between colony sizes or the activity of workers at the entrances. Roger Patterson has written at length about the queen problems he has seen, which seem to have become significantly worse recently. I have seen some of what he describes, such as supersedure of newly mated queens for apparently no reason, difficulty introducing mated queens to large colonies, and queens simply disappearing. However, it’s the failure to return from mating flights that I see most often.

Action Plan

My plans for next season to try to deal with this are:

• try to space hives irregularly, facing different directions, and use correx landing boards on hives that are making a new queen
• leave alone hives that are raising queens for longer
• concentrate my queen rearing into the months of June and July