yes there maybe the numbers but as stated it begins with the prefix Gb then the year then the number , in order to help they have to be in the correct order as they appear on the metal life ring , it may have a rubber band on it but these numbers arent important , if you manage to catch this bird it may be wing stamped still with owners details , in order to do this you need to carefully open the wing up and look at its long wing feathers stamp could be on either wing