Queen balling

[David Morland]

Today I was inspecting one of my strongest colonies, with a vigorous 2020 queen. Bees on 11 frames and up into supers, brood on 7 frames. First pass through I couldn't spot the marked queen, because the frames were crammed with bees, so I went though again blowing the bees off the frames. I came across a ball of bees, in the middle of which was the queen. They were gripping her quite tenaciously and it was difficult to separate her from them, although they immediately dived in again. I put her on the top of the frames but the workers were still homing in, with abdomens curved round. She appeared unharmed but was being pestered all the time I was able to get a picture when there were few bees clinging on and before she disappeared between the frames.
I have seen this when introducing a new queen which I can understand - any ideas why this was happening?
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