If you're intent on using the ancient Apple version of
rsync, you might find the
--dry-run option with the
-vv) options useful for listing the deletions.
rsync -rauivv --dry-run --delete SOURCE DESTINATION
If you want an affirmative record of what has been deleted, you could use the
--backup-dir= option to actually save a copy of what's been deleted in a separate folder on the DEST (which could later be deleted).
rsync -rau --delete --backup-dir=/the/destination/backup SOURCE DESTINATION
Perhaps the easiest thing to do is avoid the porting process altogether by getting a current version of
rsync via a 3rd party package manager: either MacPorts (recommended), or Homebrew.
You might also find this answer worth a read.