I photographed some cormorants recently on a reservoir near Madrid and when I looked at them on the PC I found that they had white heads and a large black crest. I suspect these are great cormorants, (possibly with leucism?) but the photos I found of great cormorants don't have such large crests. Can anyone confirm the identity of these birds?
These are just Cormorants, but of the continental race Phalacrocorax carbo sinensis that shows more white on the head. Please see the image from my ID guide - Lars Jonsson 1994. This variety is the one that breeds in the interior waters of Europe and in the Danube Delta.
I hope this helps.
Thanks. I just realised I hadn't replied to your post. Or at least, I think I did, but obviously no reply appeared (for some reason IE doesn't work properly on the website). Better late than never.
The birds in your photograph have many features of a Great Cormorant - there is a dark patch at the end of the beak (and the beak appears to be about the right length), a ruff on the left one's head, colouring which is both white and black and the wings do seem to be exactly the same, so I would suggest that these birds are indeed Great Cormorants!
Hope this helps