Last spring, I purchased 2 Carniolan Nucs from a local beekeeper and each Nuc consisted of a locally raised queen. I named them CarniW and CarniE and of these 2 hives only my CarniE survived.
In early July, the CarniE hive went into swarm mode and I pulled the queen, a few frames and some bees into a deep box and then made another 3 hives using swarm cells from the swarming CarniE hive. The hive that I am performing an autopsy on is one of these offspring from the CarniE hive.
This Nuc consisted of 2 deeps, 1 medium full of honey, a sugar block added in Jan/Feb timeframe, an upper entrance and quilt box.
Since a colony normally starts in the lower box, in late fall, and works their way up to the top, we will first take a look at what the 1st deep box looked like this spring:
We can see evidence that the cluster was very small when it died (right side of frame 2 and left side of frame 3), that it stripped most of the capped honey from the frames (right side of frame 1 and then all of frame 2-4) and that it remained in the bottom box. We can also see that the colony didn’t expand out into the sides of the box very well.
Next we will inspect deep box #2 and see if we can figure out why the cluster did not move up from the bottom box:
In the 2nd box it is very obvious that this hive was small going into the fall, for it only had filled in the equivalent of 3 frames with drawn comb and honey. It does appear that the colony may have ventured up into the second box and then perhaps back down again (as evident by the missing honey on the right side of frame 2 and on both sides of frame 3). When bees only build within the middle of the box, it is called towering. There are tricks to fix this, but we won’t go into detail here, but leave it for another day.
We also can see that the frame directly above the bees (right side of frame 2 and left side of frame 3) did have honey stores, but there was a 3-4″ gap of empty drawn comb. There are times, because of this break in honey that the bees are not aware of the honey stores above and around them.
Finally, we see that the medium super that sat above the 2nd deep box and the sugar block above that was untouched.
Finally, we need to check to see if there was any evidence of disease or pests.
In the top 2 pictures we can see that the wings of our bees look fine and that there is no evidence of deformed wing virus (passed from the Varroa mite) or K-wing virus (passed from the Tracheal mite).
The bottom left picture shows that 1) there wasn’t any moisture that accumulated on the bottom, 2) that there is no streaking of feces from a varroa sick hive and 3) that there wasn’t a huge number of bees to begin with. The area cleaned off, is from us removing the dead bees with our hive tool to ensure that their entrance was not blocked.
The bottom right picture shows that the bees had been dead for quite a while, at least long enough to mold.
- Size of the cluster when it died – Very small
- Evidence of moisture in the hive – None
- Evidence of Varroa mites – None
- Evidence of Varroa feces in the cells – None
- Evidence of Dysentery – None
- Evidence of deformed wing virus – None
- The amount of honey stores remaining – Lots of food stores remaining in the 2nd deep, the full medium super and the added sugar block.
- Evidence of pests living in the hive – None
Conclusion and other observations:
- Colony too small to survive winter – This was not a very big cluster at the start of winter as shown by the fact that they hadn’t filled out the frames on the sides and that there weren’t a large amount of dead bees in the hive.
- Colony too small to survive winter -The colony was able to move around the deep box it was in, but perhaps due to its small size it was unable to cross the gap to the honey above. Either it was tightly clustered for warm and couldn’t move, or it didn’t realize there was honey above because of the small gap in the drawn comb.
- While performing this autopsy I realized that the original CarniE hive survived winter, while all hives made from CarniE swarm cells in early July did not make it through winter, even though most had built up nicely before winter began. Last year with it being so rainy, I don’t believe the queens ever mated well.
A few things to do/changes to consider in preparing for next winter:
- Seriously consider combining all small colonies with another to give the bees a better chance of surviving the winter.
- Take a look at my homemade Nuc boxes and see if the space between the frames in the lower box is too far from the bottom of the frames in the 2nd
~ May all your wandering take you to many wonderful places!