We have a lot of sparrows where we live. I think it's because we live rural in between two villages but there is a busy ish main road to the one side of our road which puts off the cats venturing too far. Every summer the sparrows nest under the tiles in our outbuilding's on the whole row of houses. There are loads of them. Yesterday it looked like they had cleared their houses out onto the courtyard, moss, mould, feathers, twigs, string, all sorts and I haven't seen them since 
There are a few in the front hedge I've seen but mainly they appear to have gone. I have not noticed them leave like this before. Is this what they do and I've just not noticed?
Please don't turn this into a Brexit thread. I am sure they haven't left because of that. I don't think they are all training to be HGV drivers either, mores the pity- as I reckon with their lovely little personalities they'd be great but I've no idea how they'd reach the peddles.
TIA