I wonder...

...what happened here?

I saw this in my back garden and I took a photo of the nest. I couldn't see inside so I held my phone above the nest. And this is what the phone saw...

A bird's blue egg complete, and there were bits of a broken egg at its side. It is nearly November now, and approaching winter, so this must have been like this for some time.

I apologise to Chirpy for my my first derelictsunday ...see Freespiral here https://www.blipfoto.com/entry/2104604782202193469