Re: Sister queens and trials
Early on, I used sister queens in all trials to reduce genetic diversity.
But, when we compared colony metrics for sister queen colonies to
non-sister queen colonies, the variance was more or less the same. In fact, at
times the sister queen sets were more variable than the non-sister queens.
We even tried sister queens all inseminated from same drone lines - and
the variance got worse - probably as a consequence of the handling of the
queens ( back then we called it artificial insemination). This was years ago,
before people like Sue Colby really improved the insemination method (and
now its called instrumental insemination).
Regardless, I no longer use sister queens - bottom line, in most trials one
is trying to test something representative of the real world beekeeping
practices - and sister queens is NOT a routine part of beekeeping operations.
Similarly, I try to avoid 'equalizing' colonies - regardless of what one
does, the strong colonies again become strong, the weak ones will revert to
weak. Our bee counters indicate that strong colonies gain bees from their
neighbors - but don't necessarily follow traditional notions of drift - a
colony in the middle of the yard may well be the strongest, and the weak
colonies always lose bees (based on the percent of bees that return to the
hive each day)). Strong colonies may well run to ~100-105% return rates day
after day. For healthy colonies, we often see a return rate of mid-90% or
higher. The weaker ones often drop to 92%, even down to high 80% returns.
So, the strong colonies routinely gain bees, the weak ones lose bees. The
obvious conclusion, the weak colonies lose bees to the strong colonies.
(Note, the return rates are usually higher during prime foraging season when
floral resources are abundant, may fall off in early spring and fall,
possibly due to the aging of the forager force. Old bees dying). One has to
generate the mean and mode return rates for the beeyard at any given time and
place, then look for the outliers - unusually high or unusually low return
rates,
When starting a trial, rather than equalizing (adding or removing frames of
brood, etc. or swapping hive position), I prefer to either: 1) grade/rank
all of the colonies, then assign equal numbers for each grade category to
every control and treatment, randomly distributing for controls and
treatments OR 2) grade a large number of colonies and pick a set that is well
matched (as they occur - with no manipulation such as adding or removing
frames).
The first option is more easily attainable and again is representative of
real beekeeping operations, the second is better for looking at subtle
changes - but you need a large set of colonies from which to obtain the matched
colonies. To be clear, under option 1, if you establish four colony
grades (1, 2, 3, 5) based on metrics such as frames covered by bees, frames of
brood, possibly weight of colony or frames of honey, etc.), and if you have
controls and 4 treatment levels, you'd end up with each control set and
each treatment composed of a 1, 2, 3, and a 4 grade colony). All of the 1s
would be randomly assigned to the control and to each of four treatments, all
of the 2s would be randomly assigned, etc. There would be 4 control
colonies, and 4 colonies in each treatment.
Jerry
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