Colony losses

[gavin]

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.

[Jon]

I lost a colony last September which in part was my own fault.
It was one of the strongest colonies in the apiary and had two supers half full of honey at the start of August.
It then rained for three weeks.
I did a colony inspection some time around the end of August and there was not a pick of food left in the hive.
hungry bees were starting to fall off the combs. I put a feeder on straight away and they took down kilos of sugar in strong syrup.
In spite of this, the colony had dwindled to a couple of frames of bees by the end of September.
I reckon that it succumbed to a stress induced ailment brought on by reaching starvation point, possibly one of the nosemas.
The other possibility is a duff queen as this hive had tried to supersede in early July even though the queen had only been laying for 6 weeks.
Last summer I noticed a lot of the queen problems Roger Patterson has been highlighting on the BBKA site.
Were I a gambling man, I would bet on it being something to do with Nosema rather than our old friend Imidacloprid.

That left me with 13 colonies going into winter, 9 decent ones and 4 smallish nucs which I had made up from extra supersedure cells in August.
I fed them about 100k of sugar syrup in the autumn.
I had actually contemplated skipping varroa treatment as I had hardly seen a mite all year either on the trays or in drone brood.
But then mites started to appear in numbers on the trays in September so I treated.
Mite numbers double every month, and late summer is when you can see a dramatic increase.
I treated with Apiguard starting mid September, which is really a bit late.
On 22 Dec. I treated all with Oxalic acid trickle.

I was able to check between 17-19 March and all colonies were alive but one nuc was missing a queen. Another nuc had a queen with about half a frame of bees so I combined them. Another queenright nuc had dwindled to the point where I was able to tip them into an Apidea. This one is in my garden shed and the queen is laying. Another colony which was very strong in the autumn has dwindled to a frame of bees but has a laying queen. The rest of them are fine with 2-4 frames of brood.
I checked a couple this afternoon and the strongest would have no more than 6-7 seams of bees.
The reason the nucs came out of winter so weak is that they went into winter with only 2-3 seams of bees.
I really should have combined some in the Autumn but they had brand new queens and I wanted a chance to evaluate them.

So the state of play is I have 10 viable colonies and a couple of spare queens. I can use these to make nucs in early May if they are still alive.

Jon

[gavin]

I reckon that it succumbed to a stress induced ailment brought on by reaching starvation point, possibly one of the nosemas.

Interesting. My first one to go was on the point of starvation in August - bees in slow motion.

So the state of play is I have 10 viable colonies and a couple of spare queens. I can use these to make nucs in early May if they are still alive.

Do you sell bees across the Irish Sea?!

[Neils]

We went into winter with three, two technically belonging to my friend. 1 was a swarm that gave us nothing but trouble all year superseding queen after queen and as of last week it finally succumbed. His other colony is currently hanging on by a thread but we're only talking about 1-2 frames of bees at the moment. We were talking about this today to see if there was anything definite that we could out our fingers on as to what went wrong. There was a reasonable amount of chalkbrood in the colony throughout the summer, but it was numerically by far the strongest of the three colonies.

Mine went into winter preparations reasonably strong across 9 frames in total, including stores. They'd swarmed reasonably late in July and the new queen came into lay sometime in August. As the mite count had been low all year I was questioning whether to treat with Apiguard at all, but did eventually in Mid September. I gave them the first super of stores, scoring the cappings and moving the super under the brood and letting them move the stores up before removing the super completely, this still left me with 2 frames unused in the brood area and I topped up with a small amount of syrup.

Since February I've topped the colony up with fondant and late march I gave them a litre of 1:1 syrup

I deliberately didn't treat with OA over winter for a number of reasons, first I guess is that I didn't like the idea of pouring acid over the bees. While I hesitate to invoke the term "Natural Beekeeping", I do want to try and limit the amount of treatments applied to them as much as possible whilst still balancing that with the fact that a loss for me at the moment is 100% losses. Since October I've cracked the crown board twice. Once to get some idea of how strong they were, the last time to do a "half inspection" and apply an apiguard treatment.

This is about the same point that I took them over last year and they look far stronger to me now than I recall them being back then, but that might just be me.

[gavin]

Superceding queens and spring dwindling .... worth checking for Nosema? [Thinks: I ought to check my own as well!]

While I hesitate to invoke the term "Natural Beekeeping", ....

How very wise!

G.

[drumgerry]

Lost one this winter - isolation starvation. Foul tempered colony which I shook swarmed last Spring as a varroa treatment. They built up strongly again through last summer. Plenty of stores in brood frames and a super which I left them going into winter. Then I got swine flu and pneumonia and had a long stay in hossie so they never got their winter oxalic trickle. A very small cluster of dead bees left when I opened it in March.

This winter I might be tempted to try oxalic vapourisation as an alternative to breaking open the hive in midwinter. I know it presents a few hazards but if we have another winter like this one they're going to need to conserve their heat!

Gerry

[Neils]

Superceding queens and spring dwindling .... worth checking for Nosema? [Thinks: I ought to check my own as well!]



How very wise!

G.

Did cross my mind to suggest that he gets some samples off both colonies so we can get a better idea of what might have gone on. After I'd put the phone down, naturally.

[Eric McArthur]

From Gavin’s ‘Colony Losses’ thread, which itself seems to have got lost. It appears that some beekeepers, including myself, are feeling guilt at losing colonies. Could we have done it better? This might seem an unanswerable question in the light of the severe winter just past and the possibility that such winters could be the norm in future; management we can change. The weather; I wish?
However despite the fact that untoward colony losses were incurred by many – there are a favoured few, perhaps even a silent many beekeepers who came through the winter with their colonies intact or who suffered minimal loss compared with their colleague beekeepers. It would be interesting and educational if these happy individuals would perhaps tell their story – their management system, their winter preparations and, I think most importantly; the type of area where the bees are kept; viz near the coast, location relative to sea level, foraging sources, distance from colonies to these sources - even dare I say it – the type of hive! Such information could be just what is needed to give ourselves and the bees a fighting chance of survival in future years.

[This post was moved from another area to keep the discussion together. Hope everyone is happy with such interventions. Gavin the Admin]

[gavin]

I'm certainly annoyed with myself about that recent loss which may well have been avoidable. That's an excellent idea Eric to suggest that people chip in with their successes as well as their losses. The Colony Losses thread is still there in the Bee Health area below if people would like to add their comments to that one rather than start another here.

[And this]