(Great) Cormorant
Phalacrocorax carbo

Cormorants are great fishers and are capable of eating more than their own weight in fish each day. This bird is in its breeding plumage, which can be told by the white patch below the wing. This bird is most likely of subspecies sinensis, which occurs in southern and Eastern Europe and has variable amounts of white feathers on the head.
 

1-2: River Aare, Dählhölzli, Bern, 21/04/2007.