Why did this colony die?

[Lesley Hoppy]

I found that one of my two colonies was dead yesterday. I had suspected that something was amiss because they had not been flying - but I knew that they had a full super of stores going into winter and I had also given them fondant.
This colony had a 14x12 brood box - and for some reason, I placed this on top of the super. I'm sure someone on this forum recommended it as their preferred configuration....
I then put the fondant on top of the hole in the crown board. I figured that they would then find food whether they went up or down.

Yesterday it appeared that they had eaten all the stores from the super below the brood box, and had died down there. They had not moved up to take the fondant .... but I guess with a 14x12 brood box, it is some distance away.
I had treated both colonies with OA in January and all seemed well then.
My mentor tested a sample for Nosema yesterday and the results were negative.
Does anyone have any ideas as to why this might have happened?

 

[Finman]

.
If they had there brood, they do not leave them.

Too much space which kept the hive cold and they could not move up over frame gap

 

[drstitson]

that's a big space - was the brood box full before the winter or just the super?

 

[Stickyfingers]

There have been several different opinions about placing supers under the brood box but what I understood is that they move front to back and then up. Having it underneath may have isolated then once there.

 

[itma]

Yesterday it appeared that they had eaten all the stores from the super below the brood box, and had died down there. They had not moved up to take the fondant .... but I guess with a 14x12 brood box, it is some distance away.

That kinda sounds like the brood was found to be empty of stores.

My guess, without seeing it, would be that simple starvation was the likely cause of death.

Call it "isolation starvation" (couldn't reach the stores) if you like, but the fundamental cause sounds like too little stores in the hive in the autumn. Not enough autumn feeding, early enough. Then not getting the fondant close enough to the bees. And not detecting early enough that things were getting critical.
Right now is the beginning of the part of the 'winter' when stores get consumed at the fastest rate -- not when it is coldest, but when the bees are trying to build-up in anticipation of spring.
They must have been well short of the 20kg/40lb stores advised. That's almost two supers-worth.


Putting a 'half' of stores under the brood for winter is a common way of giving extra.
But its far from normal with a 14x12.
Giving the half early, and bruising it, would give them a chance to move it up and stash it in the brood box.
Having the half beneath virtually guarantees that it won't be used for brood at the start of the spring. You'd expect to be able to pull it out with all the comb empty.

 

[Erichalfbee]

I have put supers under my 14 x 12 but only with some frames of half capped stores I couldn't extract. I expected them to be moved up and they indeed were.
A 14 x 12 brood box filled with stores for the winter should be enough.
Did you by any chance check that you had fed enough?
I'm hopeless at hefting so I do weigh my hives to make sure they are full after feeding.

 

[user 6228]

...
Call it "isolation starvation" (couldn't reach the stores) if you like, but the fundamental cause sounds like too little stores in the hive in the autumn. Not enough autumn feeding, early enough. Then not getting the fondant close enough to the bees. And not detecting early enough that things were getting critical.
Right now is the beginning of the part of the 'winter' when stores get consumed at the fastest rate -- not when it is coldest, but when the bees are trying to build-up in anticipation of spring.
They must have been well short of the 20kg/40lb stores advised. That's almost two supers-worth.
...

Isolation starvation is just another way of dying by heat loss. A Low heat loss nest would mean they would be able to move if needed, and not need so muchthe stores in the first place.

 

[Lesley Hoppy]

Before winter there was some storage in the brood box but the main source was in the super underneath. This was my first winter using 14x12 and it is a pretty big space .... so I did put a big thick chunk of insulating material on top of the crown board, with a hole for the fondant container...
When taking it apart this morning I did notice some drone capped brood - and there were some drone that look as if they had died whilst emerging. There were also quite a large number of dead bees that looked like drones.
Surely drones don't emerge in late Jan/early Feb?

 

[Tom Bick]

Lots of drones and drone brood in your hive at this time of year would suggest a failed queen.

 

[Lesley Hoppy]

Lots of drones and drone brood in your hive at this time of year would suggest a failed queen.

Thanks for that Tom - I did a pretty careful sift through all the dead bodies and was surprised that I didn't find the Queen - even though she had been well marked......

 

[Tonych224]

Was the queen a 2012 mated queen??

A newbie myself and I'm guessing It maybe possible that the workers have just reached the end of their time but your queen has run out of the good stuff and had become a drone layer.

 

[Lesley Hoppy]

She was a 2012 mated queen.....maybe you are right.

 

[Tom Bick]

Your marked queen may still be there and you missed her or perhaps you had a late supercedure and the brood is from a young unmated queen.

 

[drstitson]

"Before winter there was some storage in the brood box but the main source was in the super underneath"

there's your answer.

a typical colony will need a FULL 14x12 to essentially ensure adequate stores for all winters. that's equivalent to roughly brood and half FULL.

people who put supers below either do it will full BBs or early to get the stores moved up to save on sugar.

a super plus a bit is nowhere near enough stores and coupled with the empty space above death was almost a certainty. couple that with a weak 2012 queen.....

 

[itma]

Re the drones - I'm wondering when the queen was last seen.

Being queenless in the autumn might be one reason for them being lethargic and not getting the stores in to properly fill the bb.

 

[Luminos]

So sorry about your lost colony, Lesley Hoppy
When mine died last winter I also couldn't find the queen, and was advised to look her on the OMF - sure enough, there she was.

 

[itma]

a typical colony will need a FULL 14x12 to essentially ensure adequate stores for all winters. that's equivalent to roughly brood and half FULL.

Doc, I think you are being a little excessive there.
The standard advice translates as a well-stuffed National brood - ten frames (or 9 + two halves, at the ends) using the nominal 4 lb capacity each, thus making 40 lb.

A well-stocked 14x12 on its own should provide plenty.
No dispute that a super plus 'a bit in the brood' isn't quite enough.

Question is - why was the bb so short? Did they not have a good queen in the autumn?

 

[Lesley Hoppy]

Re the drones - I'm wondering when the queen was last seen.

Being queenless in the autumn might be one reason for them being lethargic and not getting the stores in to properly fill the bb.

Last saw her in September ... but she was a late queen and maybe poorly mated. She was egg laying though...
I did look for her on the OMF but there were about 3 litres of dead bees so I could have missed her.

 

[QueenMaster]

putting stores below brood box is a very bad idea because of looting.

If a colony is looted then it happen sometimes that the queen and other bees are killed by looters during fights.

You can see looting indice with wax debris at the entrance or torn wax frames.

 

[Lesley Hoppy]

I dont think they were looted - but the lesson I have learned from this is not to put the stores below the brood box for winter.
My other colony look in good shape - and they had no super of honey - just the stores in the brood box and I have kept them fed with fondant.
The colony that died did not get through their fondant half as quickly so I assumed that they were still feeding on the stores in the super below the brood box....