Monday, September 23, 2013

Bee-friendly Super Top Bar Hive

As I already mentioned in one of my earlier posts I'm designing a new bee hive one that in my opinion suits well the bee biology and my needs as a householder. I'm not after large amounts of honey otherwise I would be keeping bees in those conventional hives which overwork bees, making 70-100 kg of honey. Im more after a modest amount of around 10-15 kg per hive. But first and foremost Im into giving my bees a cavity which suits their natural biorhythm.

The main starting point in my personal beekeeping is the fact that bee swarm prefers to settle in cavities which have a volume of 40 liters. Dr. Seeley's study of swarm behaviour demonstrates that swarms, if offered cavities between 15 to 100 litres always chose 40 litres cavities. There must be a good reason for that and Im intending to respect that preference. Im not sure what the exact volume of my short Top Bar Hives is but there are 10 top bars and each can hold a comb with close to 2 kg of honey so Im assuming it is around 40 litres because Seeley noticed that swarms in such a cavity can collect around 20 kg of stores before winter. 

Supered hive is not a new thing. Far from it. It was used for decades. Most beeks these days keep bees in such supered vertical hives. They are designed so to give as much honey harvest as possible. Design for the benefit of humans rather than bees. In such hives bees are obviously overworked by filling all these empty supers above their heads. Bees dislike empty space and will do their best to fill it with combs and stores. I would not say that the colony is trying to make a surplus of honey but rather they are trying to thermo regulate the entire cavity. The honey comb is not just their food but also a material which is very good at preserving heat, so we might say bees heat up the wax comb which preserves the heat and reflects it back onto the colony keeping them warm. Hive is a wind break and a protection from predators and rain.

I also mentioned in my earlier post that one swedish beek tried this design and got good results with it. He got 24 kg of honey from his super top bar hive but Im sure its because he had frames in his supers so he could easily extract the honey and return the empty combs for the bees to keep refilling them so to harvest again. Im more into crush and strain where honey comb is crushed entirely to extract the honey. For this reason I will harvest only once a year.

You might wonder why Im testing this design since I keep bees in horizontal TBHs which are already bee friendly. Good question :)
Yes they are indeed bee friendly and for that reason I have chosen to keep the top bar hive model for the Primary Colony Body/Cavity.  As mentioned above Im trying to give bees a cavity of about 40 litres (Dr. Seeley) and all horizontal Top Bar Hives are much larger than that. Yes one could make them smaller with the follower board but where will the bees store the surplus honey then?

You see, bees do feel their cavity/body size and act/plan according to that volume. My local inspector overwinters small splits on only 2 combs every year. These small splits seem to adapt to this small cavity and raise just enough bees and store just enough honey to pull them through the winter until the first pollen and nectar source in early spring. His small splits survive the winter on 2 combs. Fact.
But swarms do prefer 40 litres cavities and that is my starting point in designing this new hive (new for me that is).
That said bees in the regular size Top Bar Hive can sense that large space and will begin raising a lot of brood which is to fill that space with comb and stores. And here is my dilemma; how do I know what is the surplus honey that I can harvest for my own needs? You see, bees can store the same amount of honey on 10 combs as on 15 combs. On 10 combs they will store maybe 2/3 of the comb with honey and on 15 combs 1/2 of the comb. Bees always store honey in the upper part of the comb leaving some empty space at the bottom part (brood raising?). So if I believe that bees need only 10 combs to survive the winter I will very likely have to feed extra since the hind combs are the ones with most stored honey, hence called the honey area. These combs can be filled entirely with stores, not so in the brood area. So how do I know for certain that bees have enough stores if I harvest the combs with most honey in them? Bees sure arranged the whole cavity/body so its set up for the wintering yet I took away that which I believed was surplus.

A colony in a 40 litres cavity will raise less brood than those in a conventional hive and will very likely backfill the brood nest faster than those in conventional hives and for that reason will very likely go into swarming preparation much earlier. That is fine with me since early swarming also means more time for the new colony to build up before the winter.
Bee-friendly Super Top Bar Hives
 So why do I call this hive "Bee-friendly Super Top Bar Hive"?
1. its a top bar hive where bees have freedom to build natural comb with various cell size
2. the colony is not exposed to the super above since the top bars are not spaced as is the case in framed hives, and hence is not forced to fill it up with comb and stores pronto
3. there is no queen excluder
4. when the super is removed the brood nest atmosphere is preserved because the top bars aren't spaced
5. the bees feel there is a primary larger cavity and there is smaller/shallower secondary cavity. They will choose the larger (40 litres) cavity and will make sure to organise that cavity so its ready for the winter (filled with enough stores). This cavity will also dictate to a certain extent the swarming urge and the amount of brood raised during the flow and before the winter (less brood).
The secondary cavity (super) can be closed off by propolising the two 1 cm slits (second photo bellow) or if Receiver Bees (which receive nectar from foragers) decide there indeed is some surplus honey they will store it there. Im sure the bees will have more choice in such a design. If bees decide that they have better things to do than to fill that secondary cavity with honey they can easily close it off with propolis.
6. the primary cavity is never changing in volume. Supering, Nadiring and Spacing (comb manipulation in most hives) changes the hive volume all the time which forces changes on the colony level. I will do no spacing manipulation in this kind of hive.

Even though some people believe that we humans and bees are "One" (and this can be true in a mystical and spiritual way) Im approaching this hive design as if we humans and bees are not "One" but rather two different species entirely. For that reason I find it highly appropriate to have two separate cavities, one for the bee colony and one for the wretched human, my-little-self :) so none of us get confused with my hive management.
One hive with the super off and one with a super on. You can see that I placed
planks on top of the super. I will use no frames nor top bars. Bees will be able
to build wild comb in there. The planks are not fixed to the super box so its to
remove them when harvesting/cutting out the honey combs.
I have made a frame on which to place the super so bees cant propolise
the super to the top bars. The frame is 1 cm above the height of the top bars.
I decided to create 2 slits, one before the first top bar and one after the last top
bar. The grey top bar to the left is the follower board. The entrance is on the
right side of this photo.
As you can see from the back the supers are shorter than the top bar hive
so I placed another plank behind it to close the cavity. The roof is long
enough to cover the entire hive. The super is shallow only 16 cm tall.
Shallow super will discourage Queen from laying in it. Bees seem to prefer
having the brood nest in deeper spaces. Hence no need for the queen excluder.
All of the written above is simply a hypothesis of a simpleton (me) which started keeping bees last year (2012), not a scientist, not an experienced wise beek, so please if you are getting an idea to try this design take into consideration that this all might just backfire and turn into a fiasco :) I will test this next year and update you via this blog of mine. Make sure to stay tuned!

2 comments:

  1. Hi Dusko,

    I look forward to seeing your results! It's a very interesting idea. I like the idea of the shorter length top bar hive with the optional super. Will you still go into the main hive to remove old combs, etc?

    I have two top bar hives and I have been keeping them fairly small - mainly from neglect. With an infant and another on the way, my beekeeping time has been short, but I've been pleased to see that the bees have been thriving. This year is the first year I've seen the small hive beetle, but the bees had it under control and I saw no damage to the combs. In my limited experience, the less I do, the better off the bees are.

    Thanks for posting. I really enjoy reading your blog.
    Jeff

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    1. Hi Jeff,
      Good man for keeping bees in TBHs and good man for being a dad :)

      I was thinking to do a shake down (artificial swarm) every 3 years as Dennis Murrel does in his top bar hives. You either remove a few old combs each year or as Dennis does, all of it every 3 years.
      Low interferance seem to work for many beeks out there.

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