Many factors have been proposed as causes of swarming. It
is not so much a single feature that is important, but the combined
weight of all the contributing features.
Bumping into each other two types of bumping activity have
been observed. The one that is important from a triggering point of
view is that which occurs in a crowded nest partly due to the number
of bees in the volume of the nest and partly because there are nurse
bees casting about in a frantic fashion as all available cells have
freshly gathered thin nectar in them.
Reducing "queen" Pheromone
Lack of egg laying space is often missed by the beekeeper
as it may only occur for a brief time when the bees are not under
direct observation. If a sudden pulse in nectar production occurs in
a group of plants, the bees will respond by foraging in force...
bringing home much dilute nectar which is stored in the broodnest. The
nectar fills all empty cells and the queen's laying is curtailed due
to lack of empty cells. This condition does not last very long as the
nectar is concentrated and moved upwards during the night. A feature
associated with this effect is that the queen will have been fed at a
rate to sustain egg production and there will be a time lag during
which the queen may lay eggs from force of need. There will be no
cells available for this laying and the egg may be laid on the
surface of capped cells, where it may possibly be transported by a
worker and placed in a cell or simply be eaten. I am not stating
here that eggs are carried about in this manner, but I am saying it
is a possible mechanism, that may have a bearing on reports of eggs
being transferred by worker bees.
Increasing day length... This is not a direct cause, but if
it is true it adds weight to other elements and may "tip the balance".
Swarmy strain may also tip the balance in conjunction with
other factors. Largely attributed to the practices involved in skep
beekeeping it is certainly noticeable and should be avoided, simply
by non selection or re-queening with progeny of less swarmy stock.
Generated... December 2001