The birds have moved on. Another phase in their life cycles. Or, for some, an end. This nest was on the ground; blown down by the wind. Who knows how long it was empty; at any rate, very symbolic for us humans. However, the birds build it for one purpose only. To hold eggs. They don't need a place to sit, watch TV, exercise, eat meals, work on a hobby, etc. It's just for the kids. You might say they have small brains, one track minds. But, at least they do what they were created to do.
That's what I ask myself from time to time. Am I doing all I was meant to do? Writing too many food posts may be causing all this introspection. Though, introspecting can be good for us, in moderation.