I'm writing from Portugal. In the area around where we live (the coast between Lisbon and Cascais) I've seen several small family groups? of an unidentified bird. A bit bigger than a blackbird it looks completely black until it flys, when it displays a very prominent white stripe on each wing in the middle of the wing running across the wing. This stripe is hidden when standing except for a little bit. The other thing I've noticed is a double tuft of feathers just above the beak. Can some one tell me what this bird is? I think it is not a native bird as, although there are several small groups nearby, I've never seen it else where in Portugal.
I tooka photo from my car whilst moving (I wasn't driving!!) so the quality is not that good, but may be gives a better idea
Thank you in advance
ps: I probably posted this in the wrong area... but put that down to my knowledge being limited in the bird identification and forum areas...