I'd say when the "baby bird" is a population of potentially billions, having everyone down to the last domesticated lifeform read: spacecat leave - is a bit of a stretch. We might run into possibly abandoned mining or exploratory operations.

I can definitely see humanity mining our native asteroid belts and dwarf planets for materials if we ever get to a level where getting off our little blue rock somewhat permanently becomes feasible. It's not impossible for "others" to have done the same, if they're out there.