I don't agree as the birds actually being the vultures. That would make the two phrases an inversion and typically experienced song writers and poets stay away from inversions. Also, two birds who are silent suggests pain...silent birds, two innocent things who can't sing anymore. It's sad, not predatory. The circled by suggests they are circled by their own pain, their own loss of innocence. It seems like they followed the path to it's natural conclusion, and they are still following it. I agree that vultures are associated with death and the circling, but I just don't think those are the silent birds. There is the possibility of a double meaning though.
I don't agree as the birds actually being the vultures. That would make the two phrases an inversion and typically experienced song writers and poets stay away from inversions. Also, two birds who are silent suggests pain...silent birds, two innocent things who can't sing anymore. It's sad, not predatory. The circled by suggests they are circled by their own pain, their own loss of innocence. It seems like they followed the path to it's natural conclusion, and they are still following it. I agree that vultures are associated with death and the circling, but I just don't think those are the silent birds. There is the possibility of a double meaning though.