Columba palumbus (Common Wood-Pigeon)
Discussion
I found this feather in a beach, in the Aiguamolls de l'Empordà Natural Parc, Catalonia, Spain. I don't have no idea of what bird can be this feather.
Víctor
Sorry, my english is not very good, I say "I have no idea" and I want to say "I have no idea". If I make a mistake again, I'm sorry.

Val
I was just about to say heron but then realized that it has a white patch at the underside and that's something that only wood pigeons have on their tail feathers. So, it's pretty safe to say that this is from a wood pigeon (not a rock pigeon because their tail feathers are a lot shorter).