Found by Magnus Robb at Sesimbra harbour, this pale Herring could well be the first adult record for mainland Portugal. During this last weeks there as been some effort to scout the beaches and harbours in search of Glaucous and Iceland gulls!!!! This American Herring was without a doubt a good surprise!
Putative American Herring Gull Larus smithsonianus ad.
Here with Larus michahellis and Larus fuscus and showing bayonet on P7 and "w" shaped black band on P5.