> Perhaps the size of the comb in which the worker bees are raised isn't
> quite the right issue. The issue would seem to be the maximum spacing which
> will still prevent any queen from passing through, rather than the right
> spacing for allowing workers to pass through.

Thanks.  This is a more accurate statement of the problem.  Perhaps an even more
useful one would consider probabilities, rather than specifying 'any queen'.
Most designs involve trade-offs, and excluder design is no exception.  There are
a lot of questions to consider.

> Whatever the size of the worker brood comb, queens are raised in different
> sized cells. While queens from different breeds probably vary in average
> size, the smallest may still be prevented from going through an excluder
> which will allow the largest workers passage. In which case we only need
> one size excluder on the market.

Would we be happy with an excluder that let one or two percent of the queens
through if they also offered *much* less resistance to the worker bees?  Do
queens of various sources and strains vary in the dimension that is critical to
excluder function as much as the worker bees do?  For one thing, the queens of
bees raised with larger cell foundation should not be any bigger, since as you
pointed out, they are raised in queen cells built by the bees, not worker comb.

Is an excluder that offers freest possible passage to the biggest bees in use
restrain the queens of other popular strains?  Can we determine how much
restriction an excluder is causing for a given group of bees?   I recall seeing
on this list recently a post in which a member described watching queens run --
I think that was the word -- through an excluder.  What is going on?

Since my original post, I have been informed that in countries where other bees
than mellifera are used, excluders suited to the bee in question are available.

I think I have talked about a possible similarity with cows and other livestock
here before and pointed out that although livestock are often physically capable
of going through most fences, most just don't bother -- even when on the point
of starvation and in sight of good pasture.  That notwithstanding, most farmers
are familiar with 'fence crawlers', individual critters that overcome whatever
reluctance restrains the others and go through, over or under fences at will.

I'd sure like to know if any scientific work has been done on how the bees
(learn to) go through an excluder and why (usually) queens won't.  Is it
physically impossible?  Is it merely uncomfortable?  Is it possible, but
unattractive to do?

allen
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