On my birds ( RIR's ) we use 3 forms of identification the first form is a "dummy" leg band like
this the second form of ID is a wing band like
this and the third is a tattoo in the wing web..
I take a picture of the tattoo I had put in each birds wing web then load it in a "chicken ID" file on the computer. In the chicken ID file I have a picture of all the birds, there tattoo number picture, wing band number and the "dummy leg band" number..
That way you can pull up and print out all the information of a bird that was stolen and take it with you all so you have picture proof of the tattoo identification number.
Now I have to say I have never had a bird stolen (knock on wood) but Id rather be safe than sorry...
Chris