I visited Louise's boxes in middle Hindburndale tonight as she is away on holiday. She had registered some uncertainty about Box 8 on last week's visit as it appeared to be a "mass of tit nesting material but not in the form of a nest"
This material had appeared at the end of March and prompted an extra box (No 12) about 15m away as this was a 2011 Pied Fly territory (nesting in Box 8) and all the boxes in that area were occupied, or seemingly occupied, by tits.
This last week has seen the belated arrival of most of the Pied Flys and the new box (12) had a 1/2 built nest which was assumed to be this species. However, a male Pied Fly was sitting on the roof of Box 8 this evening. It then entered the box, then shot out alarm calling, as though startled by the contents
On investigation, there was a 'mass of nesting material', as described by Louise and laying on the top of this was a 'stiff' corpse of an un-ringed 2CY female Great Tit. I carefully searched underneath this bird and felt a round object, at first thought to be a covered egg. Then it wriggled. Then it stung me before blundering out of the box. Seemingly a queen Bombus lucorum or similar species. ** I have since been informed that it would have been unusual for a queen bumble bee to have left the sting in as they are apparently not barbed. It looked too large for a (solitary) worker bumble bee. Any comment?
I removed the sting from my finger and then weighed up the options. Further careful (!) investigation suggested that it indeed was an original tit nest, presumably "modified" into a mass of wool and moss by the bumble bee to form a nest, but there was no sign of any larvae or worker bees. However, the queen had stung and was therefore surely going to die in the near future. Therefore end of bumble bee nest and well as end of Great Tit nest.
Therefore I took the decision to completely clear out the box. Was that correct, or would it now wrongly influence/facilitate a scenario where a/the female Pied Fly had 1/2 built a nest in a nearby box and the male would now try and entice her into the now available Box 8?
Would be interested to know what you would have done (assuming you, too, were stung by the bee!)?