Eric Mille, a member of the French Warré e-group 'La Libera Abelo' has given
permission to forward to this group a translation of his message of 17 June.

He has hives with windows on opposite sides. For a year, he has tried
exposing some colonies to light by leaving the window shutters off. The
windows are never in direct sunlight.

The precedent for this is apparently a book called 'Au Pays des Abeilles' by
Maurice Gicquel, 1944, chapter 4, pp 78-81. Gicquel had hives that let in
light on 4 sides.

Here is Eric Mille's post:

"I compared 4 colonies exposed to daylight and 4 kept in the dark.
I compared the height of construction in each. The ones in the dark
constructed one third as much as those in the light.
The bees in the light are calmer, more populous and have fewer guards at the
entrances. The windows are lightly propolised on the upper boxes where the
honey is stored. In the part where the brood is and below it, the windows
are completely tansparent.
In the hives in the dark the windows are transparent from top to bottom and
on both sides of the hive.
The hives are in the same apiary, facing the same way. [...]"

Certainly I've noticed that exposing a hive or frame of bees to direct
sunshine can make them extraorinarily calm.

Seely and Morse will have to do their nest site selection study again, next
time including a whole set of illuminated cavities.
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David Heaf North-West Wales, UK
Warré & 'National' hives at 30 m over mean sea level
Warré beekeeping English web portal:
http://warre.biobees.com/index.html
***OR***
http://www.heaf.freeuk.com/warre/
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