I remember the first G.H.O. I ever touched. I was amazed at how little they weigh............mostly feathers. Dunno for sure, but it's body seemed to be no bigger around than my wrist.
Ah.......Pandion haliaetus. Very nice. Earlier this spring I noticed a pair of these circling over a small pond that had just been stocked with "catchable" sized trout for the local natives. I saw them take 4 in a matter of a few minutes so the local fishermen had to do with a few less fish.