Hi Allen

Before giving worker cell sizes for AM scutellata in this country, a quick
note on hybridisation. Over the past decade or so, scutellata have
hybridised with AM capensis, following man-made migrations of
capensis deep into scutellata territory. A pure capensis bee is
somewhat larger than a pure scutellata.

Today, the net result is a wide variance in worker cell sizes produced
by "natural" or "wild" scutellata. These range from about 4.3mm to
4.7mm per cell (according to the methodology on the website you
referred to). It would be foolhardy to give a mean value, due to the
variance in hybridisation. But it is another reason to furnish trap hives
with minimal (25mm) strip foundation. This means the bees can sort
the cell size out according to their degree of hybridisation.

As to varroa, our observations to date are that the natural swarms
exhibiting highest resistance are those with "advanced" hygienic
(grooming) behaviour. As you know, the commencement of capensis
worker laying behaviour in a scutellata hive leads to a near-term
collapse in colony hygiene. Thus we are very worried that the dual
influence of varroa and capensis could lead to a deep depletion in
wild swarms.

Barry Sergeant
Kyalami
South Africa