Bombus hypnorum

Such a lovely day again so I spent a few minutes having a chat with our new neighbours, the tree bumblebees! I got quite a cute pic of about 5 of them just poking their heads up to check me out, but chose this one as this is what they spend all day doing. As far as I know, this is them regulating the temperature of the nesting box.

I read they can beat their wings 11,000 times a second!