OK as the 3rd of the "musketeers", I should also respond. Geoff"s comments 
are right on the mark
Yes both 8's and 10's are used in Western Australia by both commercials and 
hobbyists, more 10's than 8's.
Reasons? Some just kept expanding what they started with, some made the 
choice. Those that chose weight as the reason for using 8's were misguided 
in my view. They are still bloody heavy when full...~34/35kg as opposed to 
~39/40kg for a 10 framer! But as Jim will endorse, they are easier to carry 
because the centre of gravity is closer to your body. However as our 
Occupational Health and Safety people will say, noone should be carrying 
them (its actually illegal, 16kg is the limit I'm told). So for newbees 
following this debate, get wise early...do as Bob recommends and fit hand 
hold cleats to all your boxes, AND invest in lifting equipment that will 
enable you to mechanically super up and take honey from your hives. Then it 
won't matter how big and heavy they are. Your hands and back will not be 
damaged as a consequence of doing the work.
As regards wild hives having only 8 combs....I have certainly seen some very 
large colonies with very long combs in the open (up to 6ft long!) which had 
only 8 combs, the outer combs being much shorter in width and length than 
the centre combs. But  I have also seen some other wild colonies built into 
confined spaces with combs going in all directions, certainly not parallel, 
and certainly not 8 in number! So although I too have heard this given as a 
reason for 8 frame boxes, I think its by no means a truism.

Again, as Geoff has pointed out, most migratory commercial outfits here use 
single brood boxes, 8's with 8 frames and 10's with 9 frames. Number of 
frames in the supers is more variable, but generally the important factor is 
keeping all hives at the same height to facilitate migration, which often 
occurs at short notice. If the flow cuts out suddenly, you can't open up 
hives to take off honey or level up because of intense robbing. So you have 
to be able to shift them full, although you can level up by adding empty 
boxes (no combs) on top of the lids. As a consequence, all the hives in most 
migratory apiaries here are a single brood box, excluder and 1super, or 2 
supers if they have been undersupered in preparation for honey removal. 
Undersupering usually is done when the first super is half to two thirds 
full, and that super will normally then be removed using a clearer board a 
week later, by which time it should be full. This process keeps the bees 
working evenly without stop/start triggers and maximises the production on 
the flow. The hives are normally shifted as doubles if possible, but your 
trucking situation must be able to cope with triples plus honey if thats 
what circumstances dictate.

My own management is however slightly different. I can only do this because 
I have loose bottoms or pollen traps underneath.  In late winter/early 
spring, I lift the hive and place a box of good combs/stickies under the 
brood box thereby increasing the broodnest to 2 boxes, and allowing the 
queen room to increase her laying area.At this stage the previously single 
brood box is usually half full of stores, mostly sealed honey but in some 
cases up to 2 frames of pollen. As spring progresses and population expands 
the remaining brood area in that box becomes filled with honey, and the 
bottom box is filled with brood. The excluder is then pushed down again and 
the old brood box is extracted in what we call the "clean out round". This 
procedure takes us through the period of greatest swarming desire and 
minimises the influence of overcrowded brood nest on swarming. Every little 
helps. We usually combine dequeening and requeening with these procedures 
which then sets the hives up for the season in their production 
configuration of 1 brood box.

All well known to established beekeepers, but perhaps useful info to 
newcomers.

Peter Detchon
On a beautiful sunny spring day in Western Australia

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