A day or so ago, while at the dining table, we heard a light 'thunk' as though something had fallen over. Nothing seemed out of place so we continued our meal.

It was when watching the antics of the 'squirrel pretending to be a bird' that I noticed the splodge on the French door, where a bird had flown into the glass, leaving behind a single, downy feather

Of the bird itself there was no sign and I suspect that it survived - if not, there are cats and foxes who would be quick to grab a free meal.