Sunday, September 29, 2013

Fall inspections: Finding the right size box for your bees

You just finished your fall inspections and everything looks great except that one hive that looks like this:

(This image has been graciously provided by member dputt88, but I had a hive looking exactly like this at the end of August. I transferred this hive into a 4 frame nuc)

The bees have filled only approximately half of the box with brood and stores. September is almost over. In my latitude that means that the bees have at most one brood cycle left (a worker brood cycle is approximately 20 days) and the bees are heading into winter with a box that is way too big for their population. What can we, the beekeepers do to help them out?

First things first, we need to determine what happened. Take a peek at the frames with brood and stores in your hive.
  • Do they look normal or is there a cause of concern? Check out my post Fall Inspection for my nucs and singles for pictures of what brood and stores look like this time of the year.
  • Do you suspect that high varroa mite levels are making it hard for your bees to maintain a healthy population? The ScientificBeekeeping site has a lot of resources on varroa and testing for varroa levels. You can find the info here.
  • Maybe your hive has a dwindling population due to laying workers. You can find out what laying workers hive looks like here.
  • Maybe you have a poorly mated queen or a drone layer. Examples and treatment options can be found here.
  • Maybe the flow stopped unexpectedly and you are seeing the last super that the bees could not complete. In this case, the boxes under this one should be full of brood and stores.
  • Maybe you were throwing supers on a bit too fast for them and the bees created a tall and narrow "chimney" of brood and stores right in the middle of the boxes and left the outside frames bare.
  • Maybe you got a little bit too enthusiastic stealing brood for your nucs in late summer and your hive did not have enough time to rebuild. This is my mistake that caused my hive to look like the picture above.
  • Maybe a myriad of other things happened that prevented your colony from building up. 
Once you figure out what happened, you need to take action in order to make sure that your colony heading into winter is:
  1. Queenright
  2. Pest and disease free or those are within manageable limits
  3. Provisioned with enough brood and stores for the size of the cluster/bee population
  4. Housed in an appropriately sized box/boxes for the size of the cluster
After making sure that #1 and #2 from the above list are covered, you need to make sure you have enough stores and provisions. The Canadian Association of Professional Apiculturists (CAPA) has published a lot of research on wintering bees on their website. Their recommend minimum wintering weight is 95 lbs. for singles and 135 lbs. for doubles with stores taking up 55 lbs. and 70 lbs. respectively. In particular, that translates roughly to 5 heavy honey frames, 2 frames of pollen and 2 frames of mostly capped brood for singles and 10 heavy honey frames, 4 frames of pollen and 4 frames of mostly capped brood for doubles. Their recommendations have worked well for me in the past 4 years.

As you go through your hive, take inventory of their resources. Is the bee population along with the existing brood and stores better suited for a single, a double or even a nuc (1 frame of brood, 1 frame of pollen and 2 heavy honey frames)?
By the time you are done with your inspection, you should have a pretty good idea what size box would be optimal for the current cluster size. If you have an appropriate box handy, you could just transfer the frames into the new box, put it on the stand, close it up and call it a day. Make sure you keep the brood frames in the middle, with the youngest brood (eggs and open brood) in the center of the brood nest, the capped brood towards the periphery of the nest and the honey frames on the outside.

Reducing the space available to the cluster of bees is not always straightforward, especially if you utilized different sized boxes for your brood boxes and supers and the bees created a "chimney" through all the boxes.

Now, allow me to take the time to explain the difference between a "chimney" and an unfinished super. A "chimney" is when the bees have utilized the middle frames on several boxes while leaving the outside frames undrawn. Your boxes will look like the picture above and the bees will have drawn out approximately half of the frames in each box while ignoring the rest. An unfinished supper, on the other hand, will also look like the picture above, but the boxes underneath it will be completely drawn out and, even more importantly, they will be full of brood and stores. You will definitely want to reduce the amount of boxes the bees occupy if you see a chimney (and that will involve re-arranging the frames into a more compact broodnest). However, if you are just dealing with an unfinished super, you have couple of options:
  1. You could just take off the super and let them overwinter on the boxes below. A modification of this approach would be to raise the super above the inner cover (you may even scratch some of the cappings) and let the bees rob it out and store the honey in the broodnest.
  2. Alternatively, you could try feeding your hive 2:1 sugar syrup (or 5:3) in an effort to help the bees finish out the super and leave it for them to overwinter in.
So, back to the worst case scenario - how to reduce the height of your stack if you have multiple sized boxes. If you have multiples of the same sized box plus an odd size, for example a deep plus couple of shallow supers or a deep plus couple of mediums, try to consolidate the multiples into one and feed to fill out the odd size. In the example above, you would consolidate the half-drawn mediums into one and feed to fill out the deep. If you have just one of each, then your best bet is to feed and let them sort it out.

In conclusion, in order to give your colony the best chance of overwintering, you want to make sure your colony is queenright, pest and disease free (or those are within manageable limits), provisioned with enough stores to last it until the first available pollen in your locality, and the colony is housed in a box/boxes that are appropriately sized for the available population.

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