Post Mortem Practice

I went out to feed one of my outyards this morning and found to my dismay that both hives were dead.

Both hives have the same or very similar characteristics. Both hives appeared to be alive exactly one week ago, and both hives were alive and queenright exactly two weeks and two days ago.

Both hives have capped brood, one more than the other and brood nests about the size and shape of a kid's football. Some of the brood is partially emerged but not all of them have their tongues out.

There is a mess of damp bees at the bottom of both hives about half an inch deep and there was a pile of bees inside one hive beneath the entrance at one corner about two inches deep.

Both hives had been robbed of all stored honey and both were being picked over by wasps and hornets.

I was unable to find a dead mite among the bees.

One queen was a split from this spring and the other was a queen I purchased from Zia Queenbee.

Both hives have been fed for the past month or so with 3:2 sugar syrup and were emptying 1.5 gallon feeders in under a week.

There did not appear to be many bees dead in front of the hives.

The hives were located on a 40 acre undeveloped piece of land surrounded by residential areas. They were in full sun until late afternoon when they were shaded by a tree.

What do you think?

Suspect #1 always has to be varroa. A couple reasons I say this. #1 Sounds like some of the dead brood had tongues extended? #2 It seems a bit late to have a lot of brood (though maybe not in your area) and queens that are still heavily laying late is quite often a sign of mite stress.
Robbing would be a seperate issue resulting from undefended hives. Have you made a real close inspection of the bottom boards. If it is mite related there should be quite a lot of dead mites there. The most likely scenario is that the hives were weakened to the point that the feed attracted robbers which the hive simply wasnt strong enough to defend. Sorry to hear about your problems, hope your other hives fare better.

Varroa is always my number one suspect, but I did look and try as I may, I could not find a mite. I could not find any mites on brood that I pulled out of the comb either.

My question is how could they have died so quickly if it were mites? I have a hive with a heavy visible mite load and it doesn't show any signs of dying yet. My hives are still bringing in pollen and are plenty active with 75 degree days. This just doesn't look like varroa to me, not yet.

You may be correct, sounds like you have an eye for what to look for. If you feel the hives were fairly strong (or especially if they werent) then your method of feeding might be my next suspect. I have seen good hives robbed out when a leaky feeder or spilled feed attracted bees from nearby hives when there was a dearth of nectar and strong hives nearby. Pesticides would seem unlikely at this time of year.

How about starvation?

Sounds like the flow in your area has stopped or slowed down badly. As a result robbing occurs much more then. Sound like they were robbed out. They may have been weakened by another cause but robbing overwhelms them and so they give up and move out to try and find a place they can defend. As the flow slows you need to reduce the openning to where they can defend themselves. When the remaining bees left then the emerging bees quickly die because there are no nurses to feed them.
Sorry.

The entrances had been reduced to a 1.5" round hole on the bottom and a 3/4" square hole on top as with all my other hives. I have four other hives in exactly the same configuration and the same feeders which are doing well.

Robbing is definitely an option, I don't know how many hives there are in that area. It is possible that there are already too many there. Incedentally, robbing was why I moved half my hives away from my home yard this summer. In the future, I'll keep them close enough to check more often.

It reminds me why I detest feeding so much. There's no really good way to do it.

On your last inspection, how wet where the first larvae, and how many bees did you see with their wings out, and not folded on their backs? Remember, it is not always the mites that kill, but the viruses that the mites spread.

Crazy Roland

Roland, I did not note anything out of the ordinary.

I am convinced that it was robbing as there does not seem to be anything close otherwise.