Hello All
I think that Eric in his new blog was implying that we're ignoring a big issue or two. Not quite fair as we have debated winter losses here, but it does seem like a good time to revisit it now. For me winter losses are not necessarily bad. It removes maladapted genetics, frees equipment for the wonderful season to come () and more than anything teaches us important lessons about our beekeeping. My beekeeping is just as imperfect as the next man's (or woman's), but I am trying to learn from my mistakes.
So, winter losses. From what I hear in the E of Scotland it may be a bad year for some, but an average year for others. There has been some informed speculation that massive losses among a few large-scale beekeepers in the east might have been Varroa-related.
My summary: Went into winter with 6, coming out with only two. One more is alive but I think that it is queenless.
Losses: one late last year, one early this year after the oxalic dribble, one in the last 2 weeks, one still alive but apparently queenless.
What happened? Not one of them had any new brood. I think that the queen shut down last autumn in at least two and never started up again. Not a good move. The one I've just lost looks like isolation starvation with stores a short distance from the cluster, and there were no eggs or brood at all. Was it a queen problem? On the other hand it had a small patch of brood on 21 March, so how is it broodless now?
What could I have done? I'm really not sure. I could and should have fed them better and earlier last autumn, but all of them left stores behind and may have failed anyway. Should I have fed them at queen-rearing time last year when the weather was awful? Maybe. Was I risking their later health by letting Varroa rip through them early last summer? Maybe, but then I know someone else who didn't treat for Varroa and had better survival. Should I have done something about their general ill-health last summer (chalkbrood, sac brood). Probably - Bailey comb change? Perhaps I need to raise more queens and selfishly keep spares for myself rather than give them away to beginners?
Was it all queen failure? Maybe not this last one. I had the trouble described in my blog with entrance blocks moving. Linchpin suggested blue tits, but there was also mouse activity in some (worst in my strongest survivor in fact). Did mice kill the queen in the one I've just lost? Or blue tits? There is a lesson there, in that last winter the perforated metal mouse guards worked reasonably well, and this winter the wooden blocks on the new mesh floors didn't. I need to find a way to keep the guards in place. Maybe I should be insulating the top of the hive too.
Why are queens failing? I'd really like to know. Most likely seems the poor weather last summer, leading to poorly nourished queens, poorly mated queens and maybe sub-standard drones too. There are other possibilities, such as more or different pesticides in the environment than previously. Is that imidacloprid-treated oilseed rape to blame? It *could* be as my queens would have been raised on the stuff last year, but let's hear what everyone else has to say first. If people are seeing queen failures only or mainly when they have been exposed to rape or some other source of insecticide then that might tell us something. Alternatively, on other fora last year people were describing similar problems away from arable agriculture. A beekeeper I know in England reports queen problems in the last few summers which disappear in batches raised late in the summer when the weather improved, so I'm keeping an open mind for now. Maybe people on this list could add to this.
Did beekeeper-applied chemicals contribute? I haven't used fluvalinate for years and always used it according to the label. Oxalic dribbling might have hastened the death of one colony, but I think that it was doomed anyway. Apiguard in late summer should have improved the bees' health and helped winter survival. I did add thymol to the syrup in the autumn, but I doubt that could be a problem.
What about autumn feed and stores? My strongest was wintered wholely on heather honey. My other survivor was fed syrup last autumn while others were at the heather, and its stores were topped up with a super of crystalised rape honey. It also had access to a small ivy flow in the late autumn, as did all the colonies.
So there we are. Could do better, should do better, but I'm thinking that queens problems are my main issue and I'm not ready (yet) to blame anything for this other than the poor weather at queen raising and mating time.
Anyone else? A summary of losses/survival and why you think your losses happened?
best wishes
Gavin
Afterthought: the one I've just lost was a 5-framer last autumn in which I never used dummy boards to close down the space (bad me). Nice solid frames of stores each side of the neat brood nest, so they'd be OK, wouldn't they?! They survived into late March, but maybe that last cold snap did for them. In which case I'm annoyed with myself as I could have done more for them. It was a swarm last summer from 10 miles away and looked rather Amm-ish, so I'd have liked to have kept them. Must have a rummage on the floor on Saturday and see if I can find the queen.
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