Ten days ago we'd seen a mystery "large lady" in our colony, and she definitely looked like a queen.
I tracked her movements for a while, but she seemed very interested in the outside, while at the same time exhibiting that "never been out before" behaviour of appearing a little nervous to leave, spending time on the front inner wall of the lodge (perhaps to warm up and sense the environment).
The next day I saw her leave the nest and after that I never saw her come back. So the mystery remains, was she definitely a queen, and if so, a daughter or the founding mother? We'll never know.
The colony had been set back so far by the inability to forage (due to weather) that it was still in decline and up until a few days ago I was estimating there were only a maxiumu of 5 bumblebees making themselves known in the nest. Though we did have this "hanger on" (literally) outside for quite a while - possibly a boy hunting a queen.
Today (20th June) was a much warmer day though - it was already about 24C at 9.30am. This encouraged more activity in the colony and after reviewing the CCTV I could see more trips being made, albeit by a small number of bees. However, the other unusual observation was one or two (seemingly) new larger bees. I'm pretty certain there are two in there at least. One made itself known last night, almost stumbling around the lodge, at one point looking like there was bedding all stuck to her tail.
No evidence of the debris today, but two larger bumbles were mooching around in the nest, and one of them flew at one point, even performed what looked like memorisation, but only partial. The size is about 20mm so they are right on the edge of large-worker vs. small queen, so I can't be sure if they are queens.
So, just as I was about to monitor the colony for its final "death" it's turned up a surprise, and who knows, maybe a resurgence in activity is on the cards?