Rookery is used to describe a place where birds get together to nest and fledge their young. It is most commonly used for crows and ravens which sometimes build nests close together in the tops of trees. The name comes from, not surprisingly, the Rook which is a common European cousin to crows.
Now you know all about crows. So I don’t need to tell you what young birds just leaving the rookery are called. Do I?
No. After all, it’s not like you’re some Bird-Call rookie. :)