Bad news. When I looked in my hives last weekend I discovered that two were broodless. This was a real surprise as just 2 weeks previous to that there was good brood to be seen, in various stages of development. The bees were surprisingly calm, so I wondered if maybe the Queen was not laying, but was there. However, today I looked again and apart from good honey being collected, and some pollen too, there is no brood at all. These two colonies are in Topbar hives, and just next to them are two colonies in polystyrene "segeberge" boxes. These other two do still have brood.
I am wondering if I need to try to unite the two broodless colonies with the two queenright ones before it gets too cold to do anything. Or might they overwinter, as they have only just (last week) stopped producing winter bees, and I can try to add a new queen in the spring - although I think that might be too far away...
Any ideas?