Black-headed Gull (Larus ridibundus)
Black-headed Gulls (Larus ridibundus) are extremely common in Geneva by the lake. On the picture above you can see 2 individuals fighting for a nice spot on a pole at sunset. You can easily recognize that they are in non-breeding plumage. When they are in breeding plumage, their head is all black, which gives them their name.
JAG