We have roughly a dozen swallow/house martin nests at work, I’ve had to isolate and take a roller shutter door out of commission due to them building a best on top of it!
We get mainly house martins, but they learnt to to an upwards roll in front of the door sensor which by the time they had completed the roll would have the door open in front of them so that they could fly in and nest in the out pre-warehouse.
Incredibly impressive – but not good in a warehouse storing Pharma.
Red kites and buzzards get on well, see loads nowadays – big release site for kites near to me here in Ireland (and near a massive pheasant breeding place too), they all roost together pretty much during the winter (helps that the butcher throws out a lot of scraps too).
Massive upsurge in birds of pray generally (except they have stopped the sea eagle re-introduction on the west coast, cost 18K a bird and they were getting shot and poisoned).
Also have woodpeckers here too they flew themselves in from the UK, proven to be UK and not Scandinavian – was just under 20 breeding pairs a few years ago in a couple of woods on the east coast (thought I was hearing things at first), getting quite successful and having to spread out through the valleys now.
which is nice.