animal: Larus ridibundus (latin); Lachmöwe (German); Black-headed Gull (English)
location: Ruegen, Germany

Black-headed Gull have a different ptilosis in winter and summer. In the winter they have a white head with only one dark spot. In summer they have a dark brown head. They are wearing the brown head in the hatch time. They become mature after two years. So they get their first brown head in there 3rd year.

It is a small gull which breeds in much of Europe and Asia, and also in coastal eastern Canada. Most of the population is migratory, wintering further south, but some birds in the milder westernmost areas of Europe are resident. Some birds will also spend the winter in the northeastern United States.

This gull is 38-44cm long with a 94-105 cm wingspan. It breeds in colonies in large reedbeds or marshes, or on islands in lakes, nesting on the ground. Like most gulls, it is highly gregarious in winter, both when feeding or in evening roosts. It is not a pelagic species, and is rarely seen at sea far from coasts.

This is a noisy species, especially at colonies, with a familiar "kree-ar" call. Its scientific name means "Laughing Gull".

The Black-headed Gull is the prefectural bird of Tokyo and the Yurikamome mass transit system is named after it.
(information partly from wikipedia)

more photos of this kind of gull:
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