After all the intriguing activity from our new queen a few days ago, I thought "that was that". I spent the evening collecting all the numerical data from her honey-water collection trips (she made 75!) and assumed she had now filled all her stores in the nest and would probably get on with the next phase of brooding.
Unforunately, though, the supplies on the nest ledge had attracted a persistent male and when they ran out, he also figured out how to get into the nest. Over the course of the next few days, despite me setting up numerous decoy supplies (which of course attracted even more bumblebees!), he continued to raid the nest over and over, and I suspect has emptied it completely of all the supplies the queen set up.
This was heartbreaking to watch especially since my intervention was not working - and I became really concerned that it would all go wrong for our queen: either she would not realise there were no supplies, and too focussed on brooding might not collect any more (not to mention the fact the weather has been unsuitable anyway. Or, she would simply run out of food for herself due to the inclement weather.
The good news is, I have seen her, so she is not simply "locked down" and ignoring what is happening in her nest. However, the bad news is, when I saw her today near the entrance she was incredible weak - barely moving. It brought back all the horrible memories from last year seeing some of our queens unable to survive. Although previously she would come to the ledge to check for honey water (that I had been removed), she wasn't doing this - she was simply too weak to come out of the nest.
It seemed to me this was a critical moment - I had to intervene to save her. Rather than go into the nest to intervene, I simply squirted some honey water into the entrance where she was resting (be careful to avoid her). It clearly worked as she spent a minute or so drinking and then moved back into the nest at about 5x the speed she had come to the entrance.
As I write I haven't seen her come for more - which seems a little odd - so I wait with baited breath to see how it unfolds. Notwithstanding, I have put supplies right at the nest entrance so that she cannot leave without discovering them.
Furthermore I have deal with the theiving male with a different strategy - I have finally captured him and intend to relocate him too far away for him to get back here. This would not be something you could do with a girl, as they are servicing their own nest. But the boys just feed, rest and mate and do not service a nest - so as I long as I take him somewhere safe, he can survive ok. My brother suggested experimenting with different distances to see how far he can/will fly. Perhaps if I had more time and less concern for our queen I would do so, but I think in this instance I'm just going to go about 10 miles in the expectation that's too far for him to navigate back from. I will report back!