Might the cluster wander about in the early part of the winter and become fixed to one spot when they start raising brood around now? But then they have little need for stores earlier, while they are broodless. Is this wandering cluster just a myth?!
Beowulf Cooper will have seen hundreds of Amm colonies in his time, so I'll trust his powers of observation for now. Here is what he wrote on the topic:
-------------------------------------------------------------------
TIGHT WINTER CLUSTERING NEAR THE ENTRANCE
Native bees tend to cluster up for winter early. The clusters are exceptionally tight and quiet, and tend to break up late. Surprisingly small clusters, if healthy, are capable of wintering through the coldest spells, although they may fail after a wet autumn when uncapped or late-fed stores remain in the hive. Where an Italian strain would die in winter with a moderate-sized cluster, despite adequate food around it, a very much smaller native cluster can survive with vigour.
Most native strains in the autumn go into winter cluster[ed] at the front of the hive. The drier conditions near the entrance and increased opportunities for cleansing flights presumably reduce the risk of dysentery, nosema and perhaps other diseases.
Particularly in the manner of tightness and size of cluster there are big variations between strains. It could be argued that this may represent degrees of introgression of behaviour patterns derived from bees of more southern type; for instance in parts of Scotland where French bees have been imported for many years in large numbers, clusters have been noticed to be less tight, with a larger minimum winter cluster size threshold, compared to districts where no such introductions have been made. The same can be said for areas of recent Italian introductions.
------------------------------------------------------------------
A little correction [] of Philip Denwood's posthumous editing of BC's notes.
Perhaps the variation he alludes to in native stock also just reflects the fact that indigenous stock is inherently variable and imported bees, which could also be variable in their own ranges, have already been bred for uniformity. Elsewhere he writes of differences in colour of native bees with the more easterly and southerly stocks brown, sometimes yellowish underneath and sometimes with the orange spots on the edge of the first one or two abdominal segments. Quite likely that the original native bee had (and still has) this kind of variant as well as a heath variant, darker and adapted for late summer abundance rather than the spring and summer flora available elsewhere.
best wishes
Gavin
