An over-wintering and passage migrant, this species tends to keep to the coast apart from during migration when it can be seen well inland. There is a great deal of difference between juveniles and adults in Common Gulls, with the head becoming whiter with age, but size is always a give-away; a distinctly larger gull than the more common Black-headed and much smaller than all other gulls in the area apart from the Audouin's Gull, from which the beak tells it apart with ease. Common Gulls have a small - for a gull - neat beak that changes with age. Starting from pale at the base with a black tip, it changes during the 2nd winter to having a broad black band two thirds of the way along with a yellowish tip. When adult the black band becomes more of a thin stripe. The head has a varying amount of longitudinal thin streaking until adulthood when it is pure white, the back is light grey and the wings at all ages have a white trailing edge with a black tip.
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