On Friday, David Eyre responded to my post about cell size and
african bees.
> On 24 Oct 97 at 11:32, Garth wrote:
> > I do't want to sound silly here but I would think the easiest way of
> > telling if a hive is africanised is to look at the cell size. Should
> > be about 5mm for all african bees, whereas it varies for euuro bees
> > but is usually a bit higher. Mine are about 4.3mm, which means that
> > they dont draw the AHB foundation I buy too well so I use a ver
> > small strip at the top of each frame. One can see the transition
>
> I had just got off the phone talking with someone in Arizona on this
> very subject of cell size when I received the above from Garth. They
> stated a correlation between cell size and Varroa infestation. It
> seems they are putting Euro bees in smaller cell foundation and not
> treating Varroa with any chemicals or medication. Could the AHB
> foundation and smaller cell size be the answer?
Firstly I think this is a great bit of research!
I think that this is probably due to the fact that the bees thus born
are going to go through a more rapid metamorphosis. I do not know
this, but would think that a fastidious hive would clean any mites
out of uncapped brood cells, hence the only time the varroa could
multiply would be when it was in the capped cell. As the natural host
of Varroa jacobsonii is the asian cavity nesting bee, Apis cerana,
which is a bit smaller than my own cape bees (about half the size
actually although I have only seen two pickled specimens) I would
think that the time A.cerana spend capped would also be quite short,
or even shorter as their cells are minute.. (I think that Ruttner in
his big book on bees whose name at present eludes me gives the brood
durations for all the Apis species) So the european bees with their
large cells must have been heaven and maybe thats why V.j multiplied
up so much? It is also interesting to note the A.cerana are supposed
to be dirty little bees that don't even clean their bottome boards
up. Apparently this is a prob as wax moth hang around there.
Out of interest, I know that there has been some mention by people
that are doing removals of bees that have survived varroa? Were those
old colonies in comb that had been packed with silk so it did not
have a large diameter anymore? Also the hive in the walnut tree
mentioned a while back? That sounded like an old hive. Paul Cronshaw
in Santa Barbara- your removals - do you have any of the combs from
the old hives left? Also Ted Wout I remember you mentioned a hive you
were taking out of an oak tree? Do you still have those combs? It
would be interesting to hear what the size of the cells was in the
brood nest? If they were close to 5.0 mm (I unfortunately cannot
convert this into inches as I dont know what the sub units are but I
think that there are about 24 mm to an inch) then they are getting
near that of african bees.
> But then Garth says that his Euro bees don't draw the foundation too
> well, meaning I suppose that our bees need larger cells?
> Discussion please!
>
On this topic, the person who introduced me to the world of bees,
Prof Randal Hepburn did some interesting work in his book 'Honeybees
and Wax' in which he put bees on various size foundation and recorded
the results. It appears that if one gives bees a size they are not
used to, they will try to get it back to their favourite size, by
drawing blank and dummy cells in amongst normal cells, giving a
strange shape cell here and there and open spaces. This would give a
bad brood pattern as the cells are not regular and some are not right
to trigger the queens layiing responses. (governed by cell width)
I should imagine that another problem would actually be how to fit a
euro queen into an AHB cell for laying an egg. Carnolians would not
be able to do it as they are just too big. Italians would I gather
be able to as they are a bit smaller, and for many years people
requeened with italians here with some success.
The plus side of thie smaller bee thing is that one gets more bees
per frame and they go faster. The down side is they have a bigger
surface area to volume ratio which means that they will cool down
faster which is why I should imagine bees in cold areas are big in
the first place.
The idea does sound fascinating though, with the though of maybe
Arizona exporting drawn AHB comb to Canada for the summer months and
then beekeepers putting their large frames back into the brood nest
for the last few brood cycles before winter and so on. Could be fun
for bee viruses and will boost tetracycline sales through the roof!!
Note: AHB dont get AFB and EFB very much.
I think in the book I mentioned earlier an experiment was carried out
which was titled 'bigger bees more honey'. Apparently the idea was
great but it flopped because of some undetermined reason. The bees
were bigger but they made much less honey. Those were AHB on
carnolian drawn frames. Oh yes, the extent to which AHB will draw
frames of EHB foundation is also variable as I gather different sizes
are available. This is different to all the african bee races which
have about the same size cells (with the exception of my silly little
bees) european bees have a large variety of cell sizes and I remember
reading somewhere that even giving carnolian size foundation to
italians gives problems with dummy cells being drawn.
In conclusion I don't think it will be as simple as just changing
over to a smaller foundation size. That would entail a change of hive
dimensions (imagine going from about 4000 cells per frame to 8600
cells a frame). That means that your potential hive population
doubles, your workforce can't fly as well in the rain, when they get
cross there are twice as many to sting the neigbours ducks to death,
extracting honey will take longer from those irritating honey filled
end frames as the cappillary attraction goes up and so on.
On the plus side it means that there may be a cheaper supplier of AHB
foundation for me!! David, who makes those guys foundation?
Keep well
Garth
PS if anybody is interested I can type out some of the bits and
pieces about the foundation size experiments after my exams. Just
give me a shout.
---
Garth Cambray Kamdini Apiaries
15 Park Road Apis melifera capensis
Grahamstown 800mm annual precipitation
6139
Eastern Cape
South Africa Phone 27-0461-311663
3rd year Biochemistry/Microbiology Rhodes University
In general, generalisations are bad.
Interests: Flii's and Bees.
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