Thoughts On November Hive Losses

Its my opinion, after having seen a number of years in a row with large amounts of bees dying in November, is that November is the toughest month of the year to get through without seeing losses. It may be that it was mild enough this year that I have't yet seen the worst for 2018, but I think I'll know in a few weeks at the most.I can't really say that this is a new phenomenon, though it might be (and I suspect it is), but there's a good chance too that I didn't notice it when I had fewer hives, and wasn't looking for it, or expecting it. I'd say its happened, to greater and lesser degrees, for the last 5 years in a row. After many years of zero, or few, losses, I suddenly saw losses of 60% one year. After that, it got better, and last year, just a few- but all in relatively the same way, and at the same time. November. Good news is (for me) that I am pretty sure I know the cause, and I know what to do about it.I'd have to say its only a theory, as I don't hear or read of anyone else thinking the same exact thing- but its close. November in the PNW has two special qualities. It gets wet, and it gets, somewhere near the end, cold. Not super cold like some places, and not as cold as it will be in December and January, but its the first cold, with frost, and usually a lot of rain. Happens every year. A warm week or two, some rain, but suddenly, overnight, a sudden temperature drop for a few days. Every year for the past 5 I have seen the same thing happen (and others I know here have as well). Towards the end of November i look at an apiary and at least one hive, sometimes more, is losing a lot of bees. They are strewn out front in a carpet of dead, or dying, bees. Some years they fall like rain inside the hive and fill the bottom board, and I have to scrape them out. Day after day they keep raining down. But not in all hives. And not in any particular ones (like small ones, or ones without a lot of stores). It seems to be random. In most cases, it continues until the hive is completely dead. Not always- but its the first sign that something is wrong, and its not normal (there is always winter loss of older bees- this isn't that). Some hives might lose a lot of bees, but succumb later. In the past I was mystefied- they have food, they are well protected, they are strong hives with lots of stores, they have had two strong mite treatments in the past 3 months, they all have this year's queens, or at most, a two year queen. For a few years I thought it was a moisture problem- and spent time dealing with that. I couldn't figure it out, but I think I know now. And its the same song that everyone is singing: mites. Duh. But in this case, I think I recognize a pattern, and one that I think I can learn to manage better in the future, and possibly did this year. What happens I think is this: I start the year working hard to do all the right things. I count mites, I check for disease, I ensure good pollen supplies, I don't muck with the hives too much, but make sure the queen is laying healthily, and that I treat for mites in a timely way. However, I am pretty sure that I haven't perfected that last step- and the hives that go down, although I feel like they've been adequately treated, are in fact infested, despite treatments. And it doesn't show up in a sugar roll mite count, which is what I do. And when I do a strong treatment, the mite drop isn't radically different than other hives. Yet I think it actually is- but I am not seeing it. So- what happens is that I am moving into September/October with some hives more diseased than others- and mites mean DWV, and DWV means an inability to thermally regulate the hive temperature. And those are the bees that drop with the first cold.They don't die when its 50F- but drop into the 40s, or 30s, and they are helpless. They die in minutes. I've see it- bees healthy looking on minute, and dead the next after exposure to cold. Its not normal. The bees that are sickest of course, are those that are born while mite infested- which speaks obviously to the futility of doing anything about it after the death toll has started. After October, maybe even the beginning of October, its too late to do anything- the die is cast- you can treat for mites, but you can't treat for DWV. So for example, I have a hive right now which has a thick carpet of dead bees in front of it, among other hives that either have none, or few. That they hive bees strewn out is actually a good sign in a way- in that there are enough bees still alive to haul them out- though not far. Possibly, other hives equally sick, just are stronger and hauling their dead further away- I don't know. But the fact is, eventually there aren't any bees to do this work, and the bees just die in the hive- and you don't see any dead bees in front- which makes one think its all OK- but it isn't at all. Among the dead, and the crawling dead, of this particular hive, I do find young bees with DWV. I can't say I always do- but I wouldn't be surprised. This is an obvious sign of mites- and a clear message that my treatments weren't successful, and the bees now hatching are likely diseased. My feeling now is to let these hives go. Emergency feed them if needed, give them a chance, but don't try any emergency mite treatments now (except the absolutely required January 1 OAV treatment - I am totally convinced this is essential). And I am fairly convinced that it is a drop in temperature- say to 40 F- that catches them offguard- and kills them in droves. For some reason, they can't manage it- they don't do what they need to do to up their temperature- and they drop. At first, lethargic, but in minutes, dead. I've seen it again and again. It isn't however, the cold that is at fault here. A healthy bee survives fine, even in far colder temperatures. A sick bee doesn't get the signal to do anything. The solution is definitely not to insulate the hives, or raise their temperature. Doing so only incubates the disease- these bees are better dead. And the solution is to be preemptive. It needs to happen in September, or earlier, and its dealing with mites. Its obvious- but I am always so surprised about the number of beekeepers who do nothing- and just count on luck. I'd say easily more than half of beekeepers I talk to. Its amazing. I am convinced that I can do better- that i can get this down to low numbers. I am hopeful that this year will prove to be a good one- that what I did this past year will help some- but there is still some bad weather to come, and I am not sure if its gotten bad enough yet to harvest out the sick bees. I also don't know if the disease spreads- in past years I was convinced of it- but I wonder now- if I just wasn't seeing a number of adjacent hives that were infested, but not spreading the disease ( I mean in winter- obviously at other times of the year drift would in fact do this).