Chroicocephalus ridibundus. (Linnaeus, 1766) The Black-headed Gull ( Chroicocephalus ridibundus) 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.
The common gull has a length of 38 to 44 cm and a wingspan of 98 to 105 cm. Its flight speed is about 10 meters per second. It breeds mainly on the ground and prefers humid environments of marshes or reeds. Like all gull species, it is very sociable in winter, both when caring for the young and when it is in mating season. It is not a pelagic species and is rarely seen offshore from the coast.
During the flight the white margin of the wings is a good visible point from afar. The male has a dark brown head, a light gray body, black dots on the wings and reddish legs. The hood gets lost in winter and leaves only vertical stripes. His voice, can be defined by the onomatopoeic term "creire" for the typical "crei-crei" repeated several times. This species of gull sometimes feeds on the coasts and in landfills.