Do you see any DWVs on the dead bees? Are they the normal looking bees or the diseased bees?
What do you use to treat the hives back in Sept? At that time is there any cap broods inside when
you treated them?

 

Treating in September is a month late . Did you do a sugar roll and count mites to see how well your treatment worked?

 

We had a warm day Sunday and the bees broke cluster, so what your seeing is the result of the undertaker bees doing their job. IMO, what it is, is. Resist the urge to take the hives apart.
Like beepro asked, what treatment did you apply?

 

You should be able to open your hives and do no damage looking into them to find out whether they are alive or not. A strong/healthy hive can stand having the lid removed this time of year where you live. Don't be surprised if you find all three hives to be dead or having few bees in them. Especially the one(s) that had been getting robbed earlier.

Sorry.

 

I treated with MAQS in September. The mite count was fine after. The robbing was in early October and it was pretty bad. Had many dead bees, but were mostly from fighting and dead wasps. Now they are just dead bees and many more since I closed them for winter. I did not do another sugar role in October before I closed them up. I will look tonight at the bodies for any signs of disease. The three hives probably had 1000 dead bees on the ground. My set up is two deep boxes and last time I checked they were full bees, brood and honey. Everything seemed fine on October 20 when I closed them up for the winter. I was just surprised to see the large amount of dead bees.

 

The three hives probably had 1000 dead bees on the ground.

A thousand dead bees from 3 hives. Lets take a short lesson in bee biology and arithmetic. Summer bees live 6 to 8 weeks, and it's 3 weeks from egg to bee, so the dead bees are likely from eggs laid of 9 to 11 weeks ago, call it 10 weeks for an average. Queen lays 1500 eggs a day in peak season, and tapers to zero during the broodless winter period. Count back 10 weeks from today, puts us at mid to late August. Realistically, queen would still be laying then, probably at a reduced rate, for arguement sake, 500 or so a day. Those would be the last summer bees, ie, the ones that raise and care for the brood that will become the longer lived winter bees, and, they would be dying of age in this time period.

1000 dead bees from 3 healthy hives at this time of the year, not at all an indication of a hive problem. If the bees died cuz they were sick, then it's a problem, but if it's just the normal aging cycle, nothing to be concerned about. We dont normally see piles of dead bees in front of hives in the summer, for two reasons. Many die away from the hive when out foraging, many more fly out to die. In summer when it's warm, the undertakers will fly some distance carrying a dead bee. But it's cold now, and the colony has switched to a mode of 'preserve energy' because a cold bee is a dead bee. Undertakers wont fly away so far because it's colder out, and they are trying to preserve energy, so dead bees get dumped right out the entrance at this time of the year.

This is the time of year (depending somewhat on location / climate) where the population is finishing the fall turnover with the last of the short lived summer bees coming to end of life, leaving the hive with just the longer lived winter bees to carry on. These bees originated at a time when the queen was still laying at a decent rate, so, there will be quite a few of them.

 

Remove the mouse guard and the entrance reducer and sweep out any dead bees you see on the bottom of the hive. Do this gently and carefully so you don't engage or injure any live bees who may be clustered on the lower edges of the frames. A bit of smoke wouldn't hurt.

Now you've cleared the decks for an ongoing analysis of the current rate of dead bees falling on to the bottom (whether removed from the hive or not).

Every day or two, open up the entrance reducer and see what you can see.

The comment above about the morgue bees opportunistically removing an accumulation of dead bees during a warm period sounds right to me. But time will tell. I have occasionally seen alarming, even sustained, bursts of dead bees in the winter, too, but those have never resulted in a dead colony over the winter. Usually when I do as I have suggested to you above, I find that what I was looking at was a one-off event.

A thousand dead bees divided among three colonies averaged out over 19 days isn't a lot per day (<18/day) in colonies that may still have 20K+ bees. Examining the dead ones may also give you a clue: are they by and large older bees with worn out wings? Drones? These two classes have no benefit to the wintering colony so their loss is not a negative. You can also do an alcohol wash on them to check the level of varroa. (This will not be a precise number as it might be if the bees were still alive, but really kind of a pass/fail, meaning finding a lot of varroa, or finding nearly none.) If you have access to a microscope you could also check them for Nosema, or even tracheal mites.

Nancy

 

And there I was, concerned about the 5 or so dead bees I saw on the bottom board behind the robber screen on a day the bees weren't flying. Feeling a little better. Still worried cause this is the nuc that was a neighbor to the one that crashed last week. At least the mortality makes sense.

 

Without going into the hive JWP, how do you know that the 5 dead bees wasn't the last bees of this nuc hive?
I went in to do a hive check today and saw many newly emerged bees. This is an indication that my nuc hive is
still flourishing without the mites to bother them. Still have plenty of new and old nurse bees with the laying queen.

Facing this situation of not knowing the status of this hive, if I'm the OP, I would go in for a hive check. If this hive is
totally gone then I would salvage the drawn comb for next season. If they are still alive then I'll make sure that they have
the sugar bricks on top to continue feeding. In my bee world nothing is certain until I find out the truth behind it.

 

I had been in the nuc two days prior to drop in the Apivar strip and it was still full of bees, about three and a half full frames worth. But you never really know except for the actual day you inspect. Been cold and wet here the past week and dropping into the 20s tomorrow. Have to wait and see how things are doing.