Jerry wrote

> > We have many years of data regarding rates of supercedure in commercial
> bee
> > operations in the Northwestern states - marked queens, 10-12 colonies
per
> > apiary, many apiaries, many years.

Dr. Basil Furgala did some work in his part of the world and found that up
to 50% of the queens put in a hive were not there after a year.  I will have
to look up my notes from our trip to the USA and Canada in 1986 when we
visited Basil at his University.  This work was pre mites.

Studies here in Australia have found that up to 30% are not there after that
time also.  There are many reasions for this and Jerry and Peter have listed
a lot of the reasons.

Allen wrote

> People often talk about supercedure as if it somehow reduces production,
> but in my understanding, it should not.  In fact, I should think that
> supercedure might often increase populations if the two queens co-exist
for
> some time, and should in the long term assure continuity of the colony.

In my experince this is not the case.  We have had breeders that supercede
and I have caught the daughter queen and left the mother behind.  I have
found in all cases, about 5 or 6, that the mother does not come back on the
lay.  I am assuming that she stops laying when the daughter takes over.  The
daughter would only have been laying for about a week maximum, in reality
probably only about 3 or 4 days.

I calculate this by knowing when I last grafted from that hive and I would
have examined all combs and destroyed any queen cells.

Trevor Weatherhead
AUSTRALIA