Something to note was when I opened one of my nucs that was a swarm from last year I noticed that it sounded different to the others. It was much noisier which in my experience can be one of the signs that the hive was queenless.
Indeed it was! . On quick closer inspection there were no eggs or larvae but still some brood on three frames which must mean that the queen died (stopped laying) about 2 weeks ago or just after my second treatment. fortunately the bees knew this and immediately have constructed 2 queen cells ( in the middle of the frame) and have sealed each queen cell. Hopefully with warmer temperatures for the next week this will precipitate a sucessfull hatching but the real problem ahead is that as it is so early in the year will there be enough drones around for her to sucessfully mate with? Time will tell. I will leave them alone for another 3 weeks and see what happends!!
Honey Bee on Camelia shrub. A rich source of early pollen!